EVALUATION KIT AVAILABLE 71M6545T/71M6545HT General Description The 71M6545T/71M6545HT metrology processors are based on Maxim Integrated's 4th-generation metering architecture supporting the 71M6xxx series of isolated current sensing products that offer drastic reduction in component count, immunity to magnetic tampering, and unparalleled reliability. The 71M6545T/71M6545HT integrate our Single Converter Technology(R) with a 22-bit delta sigma ADC, a customizable 32-bit computation engine (CE) for core metrology functions, as well as a user-programmable 8051-compatible application processor (MPU) core with 64KB flash and 5KB RAM. An external host processor can access metrology functions directly through the SPI interface, or alternatively through the embedded MPU core in applications requiring metrology data capture, storage, and preprocessing within the metrology subsystem. In addition, the devices integrate an RTC, DIO, and UART. A complete array of ICE and development tools, programming libraries, and reference designs enable rapid development and certification of meters that meet all ANSI and IEC electricity metering standards worldwide. The 71M6545T/71M6545HT operate over the industrial temperature range and come in a 64-pin lead(Pb)-free package. Applications Three-Phase Residential, Commercial, and Industrial Energy Meters Ordering Information and Typical Operating Circuit appear at end of data sheet. Energy Meter ICs Benefits and Features SoC Integration and Unique Isolation Technique Reduces BOM Cost Without Sacrificing Performance * 0.1% Typical Accuracy Over 2000:1 Current Range * Exceeds IEC 62053/ANSI C12.20 Standards * Four-Quadrant Metering * 46-64Hz Line Frequency Range with the Same Calibration * Phase Compensation (10) * Independent 32-Bit Compute Engine * 64KB Flash, 5KB RAM * Built-In Flash Security * SPI Interface to Host with Flash Program Capability * Up to Four Pulse Outputs with Pulse Count * 8-Bit MPU (80515), Up to 5 MIPS (Optional Use) * Full-Speed MPU Clock in Brownout Mode * Up to 29 Multifunction DIO Pins * Hardware Watchdog Timer (WDT) * UART for AMR or Other Communication Duties * I2C/MICROWIRE(R) EEPROM Interface Innovative Isolation Technology (Requires Companion 71M6xxx Sensor, also from Maxim Integrated) Eliminates Current Transformers * Four Current Sensor Inputs with Selectable Differential Mode * Selectable Gain of 1 or 8 for One Current Input to Support Neutral Current Shunt * High-Speed Wh/VARh Pulse Outputs with Programmable Width Digital Temperature Compensation Improves System Performance * Metrology Compensation * Accurate RTC for TOU Functions with Automatic Temperature Compensation for Crystal in All Power Modes Power Management Extends Battery Life During Power Outages * Two Battery-Backup Modes * Single Converter Technology is a registered trademark of Maxim Integrated Products, Inc. MICROWIRE is a registered trademark of National Semiconductor Corp. 19-6721; Rev 5; 12/15 -- Brownout Mode (BRN) -- Sleep Mode (SLP) Wake-Up on Pin Events and Wake-On Timer * 1A in Sleep Mode 71M6545T/71M6545HT Energy Meter ICs TABLE OF CONTENTS General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Benefits and Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Recommended External Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Hardware Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Analog Front-End (AFE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Signal Input Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Input Multiplexer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Delay Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 ADC Preamplifier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Analog-to-Digital Converter (ADC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 FIR Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Voltage References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Isolated Sensor Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Digital Computation Engine (CE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Meter Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Real-Time Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Pulse Generators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 XPULSE and YPULSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 VPULSE and WPULSE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 80515 MPU Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Memory Organization and Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Program Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 MPU External Data Memory (XRAM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 MOVX Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Dual Data Pointer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Internal Data Memory Map and Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Special Function Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Timers and Counters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Interrupt Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 External MPU Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 On-Chip Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 www.maximintegrated.com Maxim Integrated 2 71M6545T/71M6545HT Energy Meter ICs TABLE OF CONTENTS (continued) Flash Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 MPU/CE RAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 I/O RAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Crystal Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 PLL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Real-Time Clock (RTC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 RTC Trimming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 RTC Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Battery Monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Digital I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Two-Pin EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Three-Wire EEPROM Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 SPI Slave Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 SPI Safe Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 SPI Flash Mode (SFM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Hardware Watchdog Timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Test Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Battery Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Brownout Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Sleep Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Applications Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Connecting 5V Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Direct Connection of Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Using the 71M6545T/HT with Local Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Using the 71M6545T/HT with Remote Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Metrology Temperature Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Connecting I2C EEPROMs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Connecting Three-Wire EEPROMs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 UART . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Emulator Port Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 MPU Firmware Library . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Meter Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 www.maximintegrated.com Maxim Integrated 3 71M6545T/71M6545HT Energy Meter ICs TABLE OF CONTENTS (continued) Firmware Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Overview: Functional Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 I/O RAM Map: Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 Reading the Info Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 CE Interface Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 CE Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 CE Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 CE Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 CE Input Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Status and Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Transfer Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 Pulse Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56 CE Flow Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Typical Operating Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66 www.maximintegrated.com Maxim Integrated 4 71M6545T/71M6545HT Energy Meter ICs LIST OF FIGURES Figure 1. I/O Equivalent Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Figure 2. 71M6545T/HT Operating with Local Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Figure 3. 71M6545T/HT Operating with Remote Sensor for Neutral Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Figure 4. Multiplexer Sequence with Neutral Channel and Remote Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 5. Multiplexer Sequence with Neutral Channel and Current Transformers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Figure 6. Waveforms Comparing Voltage, Current, Energy per Interval, and Accumulated Energy . . . . . . . . . . . . . . 36 Figure 7. Typical Voltage Sense Circuit Using Resistive Divider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 Figure 8. Typical Current-Sense Circuit Using Current Transformer in a Single-Ended Configuration . . . . . . . . . . . . 38 Figure 9. Typical Current-Sense Circuit Using Current Transformer in a Differential Configuration . . . . . . . . . . . . . . 38 Figure 10. Typical Current-Sense Circuit Using Shunt in a Differential Configuration . . . . . . . . . . . . . . . . . . . . . . . . . 38 Figure 11. 71M6545T/HT Typical Operating Circuit Using Locally Connected Sensors . . . . . . . . . . . . . . . . . . . . . . . 39 Figure 12. 71M6545T/HT Typical Operating Circuit Using Remote Neutral Current Sensor . . . . . . . . . . . . . . . . . . . . 40 Figure 13. Typical I2C Operating Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 14. Typical UART Operating Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 15. Typical Reset Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 16. Typical Emulator Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41 Figure 17. CE Data Flow--Multiplexer and ADC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Figure 18. CE Data Flow-- Offset, Gain, and Phase Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Figure 19. CE Data Flow--Squaring and Summation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 www.maximintegrated.com Maxim Integrated 5 71M6545T/71M6545HT Energy Meter ICs LIST OF TABLES Table 1. ADC Input Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Table 2. Inputs Selected in Multiplexer Cycles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Table 3. CKMPU Clock Frequencies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Table 4. Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Table 5. Internal Data Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Table 6. Special Function Register Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 7. Generic 80515 SFRs: Location and Reset Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 Table 8. Timers/Counters Mode Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Table 9. External MPU Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 Table 10. Test Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Table 11. Info Page Trim Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 Table 12. I/O RAM Locations in Numerical Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44 Table 13. I/O RAM Locations in Alphabetical Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47 Table 14. Power Equations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Table 15. CE Raw Data Access Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57 Table 16. CE Status Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Table 17. CE Configuration Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Table 18. Sag Threshold and Gain Adjustment Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Table 19. CE Transfer Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Table 20. CE Pulse Generation Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Table 21. Other CE Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Table 22. CE Calibration Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62 www.maximintegrated.com Maxim Integrated 6 71M6545T/71M6545HT Energy Meter ICs Absolute Maximum Ratings (All voltages referenced to GNDA.) Supplies and Ground Pins VV3P3SYS, VV3P3A................................................-0.5V to +4.6V VBAT, VBAT_RTC...................................................-0.5V to +4.6V GNDD....................................................................-0.1V to +0.1V Analog Output Pins VREF........................-10mA to +10mA, -0.5V to (VV3P3A + 0.5V) VDD...........................................-10mA to +10mA, -0.5V to +3.0V VV3P3D.....................................-10mA to +10mA, -0.5V to +4.6V Analog Input Pins IADC0-7, VADC8-10............................-10mA to +10mA, -0.5V to (VV3P3A + 0.5V) XIN, XOUT...............................-10mA to +10mA, -0.5V to +3.0V DIO Pins Configured as Digital Inputs.....-10mA to +10mA, -0.5V to +6.0V Configured as Digital Outputs.............-10mA to +10mA, -0.5V to (VV3P3D + 0.5V) Digital Pins Inputs (PB, RESET, RX, ICE_E, TEST)............-10mA to +10mA, -0.5V to +6.0V Outputs (TX)........... -10mA to +10mA, -0.5V to (VV3P3D + 0.5V) Temperature Operating Junction Temperature (peak, 100ms).............. +140C Operating Junction Temperature (continuous)................. +125C Storage Temperature......................................... -45C to +140C Lead Temperature (soldering, 10s).................................. +300C Soldering Temperature (reflow)........................................+260C Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Electrical Characteristics (Limits are production tested at TA = +25C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization.) PARAMETER CONDITIONS MIN TYP MAX UNITS V RECOMMENDED OPERATING CONDITIONS VV3P3SYS and VV3P3A Supply Voltage Precision metering operation 3.0 3.6 PLL_FAST = 1 2.65 3.8 PLL_FAST = 0 2.40 3.8 VBAT_RTC 2.0 3.8 V Operating Temperature -40 +85 C VBAT V INPUT LOGIC LEVELS Digital High-Level Input Voltage (VIH) 2 Digital Low-Level Input Voltage (VIL) V 0.8 V Input Pullup Current, (IIL) E_ RTXT, E_RST, E_TCLK 10 100 A Input Pullup Current, (IIL) OPT_ RX, OPT_TX 10 100 A Input Pullup Current, (IIL) SPI_ CSZ (SEGDIO36) 10 100 A Input Pullup Current, (IIL) Other Digital Inputs -1 +1 A Input Pulldown Current (IIH), ICE_E, RESET, TEST 10 100 A Input Pulldown Current, (IIH) Other Digital Inputs -1 +1 A www.maximintegrated.com Maxim Integrated 7 71M6545T/71M6545HT Energy Meter ICs Electrical Characteristics (continued) (Limits are production tested at TA = +25C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization.) PARAMETER CONDITIONS MIN TYP MAX UNITS OUTPUT LOGIC LEVELS Digital High-Level Output Voltage (VOH) ILOAD = 1mA VV3P3D - 0.4 V ILOAD = 15mA (Note 1) VV3P3D - 0.8 V Digital Low-Level Output Voltage (VOL) ILOAD = 1mA 0 0.4 V ILOAD = 15mA (Note 1) 0 0.8 V VBAT = 2.0V -3.5 +3.5 VBAT = 2.5V -3.5 +3.5 VBAT = 3.0V -3.0 +3.0 VBAT = 3.8V -3.0 +3.0 BATTERY MONITOR Battery Voltage Equation: 3.3 + (BSENSE - BNOM3P3) x 0.0252 + STEMP x 2.79E-5 V Measurement Error Input Impedance Passivation Current 260 IBAT(BCURR = 1) - IBAT(BCURR = 0) 50 % k 100 165 A TEMPERATURE MONITOR 22.15 + STEMP x 0.085 - 0.0023 x STEMP x [(STEMPT85P - STEMPT22P)/ (T85P - T22P) - 12.857] Temperature Measurement Equation Temperature Error (Note 1) TA = +85C -3.2 +3.2 TA = 0C to +70C -2.65 +2.65 TA = -20C -3.4 +3.4 TA = -40C -3.8 +3.8 VBAT_RTC Charge per Measurement 2 Duration of Temperature Measurement after TEMP_ START 22 www.maximintegrated.com C C C 40 ms Maxim Integrated 8 71M6545T/71M6545HT Energy Meter ICs Electrical Characteristics (continued) (Limits are production tested at TA = +25C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization.) PARAMETER CONDITIONS MIN TYP MAX UNITS VV3P3A = VV3P3SYS = 3.3V; MPU_DIV = 3 (614kHz MPU clock); PLL_FAST = 1; PRE_E = 0 5.5 6.7 PLL_FAST = 0 2.6 3.5 PRE_E = 1 5.7 6.9 PLL_FAST = 0, PRE_E=1 2.6 3.6 0.4 0.6 mA/MHz +300 nA 3.2 mA SUPPLY CURRENT VV3P3A + VV3P3SYS Supply Current (Note 1) Dynamic Current Mission mode VBAT Current -300 Brownout mode 2.4 Sleep mode VBAT_RTC Current Flash Write Current -300 mA +300 nA Brownout mode 400 650 nA Sleep mode, TA 25C 0.7 1.7 A Sleep mode, TA = 85C (Note 1) 1.5 3.2 A Maximum flash write rate 7.1 9.3 mA VV3P3D SWITCH On-Resistance VV3P3SYS to VV3P3D, IV3P3D 1mA 11 VBAT to VV3P3D, IV3P3D 1mA 11 IOH 9 mA INTERNAL POWER FAULT COMPARATOR Response Time 100mV overdrive, falling 20 200 100mV overdrive, rising 200 s Falling Threshold, 3.0V Comparator 2.83 2.93 3.03 V Falling Threshold, 2.8V Comparator 2.71 2.81 2.91 V 47 136 220 mV Falling Threshold, 2.25V Comparator 2.14 2.33 2.51 V Falling Threshold, 2.0V Comparator 1.90 2.07 2.23 V Difference between 2.25V and 2.0V Comparators 0.15 0.25 0.365 V 3.0V comparator 13 45 81 2.8V comparator 17 42 79 2.25V comparator 7 33 71 2.0V comparator 4 28 83 Difference between 3.0V and 2.8V comparators Hysteresis www.maximintegrated.com TA = +22C mV Maxim Integrated 9 71M6545T/71M6545HT Energy Meter ICs Electrical Characteristics (continued) (Limits are production tested at TA = +25C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization.) PARAMETER CONDITIONS MIN TYP MAX UNITS 2.55 2.65 2.75 V mV 2.5V REGULATOR VV2P5 Output Voltage VV3P3 = 3.0V to 3.8V, ILOAD = 0mA VV2P5 Load Regulation VBAT = 3.3V, VV3P3 = 0V, ILOAD = 0mA to 1mA 40 ILOAD = 5mA 440 ILOAD = 0mA 200 Dropout Voltage PSSR ILOAD = 0mA 5 mV mV/V CRYSTAL OSCILLATOR Maximum Output Power to Crystal 1 W PLL PLL Settling Time Power-up 3 PLL_FAST transition, low to high 3 PLL_FAST transition, high to low 3 Mode transition, sleep to mission 3 ms VREF VREF Output Voltage TA = +22C VREF Output Impedance ILOAD = -10A to +10A VREF Power Supply Sensitivity VV3P3A = 3.0V to 3.6V For 71M6545T VREF Temperature Sensitivity (Note 1) VREF Error (Note 1) For 71M6545HT 1.193 -1.5 1.195 1.197 V 3.2 k +1.5 mV/V VREFT = VREF22 + (T-22)TC1 + (T-22)2TC2 V TC1 = 151 - 2.77 x TRIMT V/C TC1 = 33.264 + 0.08 x TRIMT + 1.587 x (TRIMBGB TRIMBGD) V/C TC2 = -0.528 - 0.00128 x TRIMT V/C2 71M6545T (-40C to +85C) -40 +40 71M6545HT (-40C to -20C) -16 +16 71M6545HT (-20C to +85C) -10 +10 -250 +250 mV Peak -31.25 +31.25 mV Peak ppm/C ADC Recommended Input Range (All Analog Inputs, Relative to VV3P3A) Recommended Input Range, IADC0-IADC1, Preamp Enabled Input Impedance fIN = 65Hz 40 100 k ADC Gain Error vs. Power Supply VIN = 200mV peak, 65Hz, VV3P3A = 3.0V to 3.6V -30 +70 ppm/% www.maximintegrated.com Maxim Integrated 10 71M6545T/71M6545HT Energy Meter ICs Electrical Characteristics (continued) (Limits are production tested at TA = +25C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization.) PARAMETER Input Offset Voltage CONDITIONS MIN Differential or single-ended modes -10 TYP MAX UNITS +10 mV 250mV peak, 65Hz, 64k points, Blackman-Harris window, FIR_LEN = 2, ADC_DIV = 1, PLL_FAST = 1, MUX_DIV = 2 -93 20mV peak, 65Hz, 64k points, Blackman-Harris window, FIR_LEN = 2, ADC_DIV = 1, PLL_FAST = 1, MUX_DIV = 2 -90 LSB Size FIR_LEN = 2, ADC_DIV = 1, PLL_FAST = 1, MUX_ DIV = 2 151 nV Digital Full Scale FIR_LEN = 2, ADC_DIV = 1, PLL_FAST = 1, MUX_ DIV = 2 2,097,152 LSB THD dB PREAMPLIFIER Differential Gain 7.88 7.98 8.08 V/V Gain Variation vs. Temperature TA = -40C to +85C (Note 1) -30 -10 +15 ppm/C Gain Variation vs. V3P3 VV3P3 = 2.97V to 3.63V (Note 1) -100 +100 ppm/% Phase Shift (Note 1) +10 +22 m 9 A Preamp Input Current THD, Preamp + ADC Preamp Input Offset Voltage Phase Shift Over Temperature 3 6 VIN = 30mV -88 VIN = 15mV -88 IADC0 = IADC1 = VV3P3 + 30mV -0.63 IADC0 = IADC1 = VV3P3 + 15mV -0.57 IADC0 = IADC1 = VV3P3 -0.56 IADC0 = IADC1 = VV3P3 - 15mV -0.56 IADC0 = IADC1 = VV3P3 - 30mV -0.55 (Note 1) -0.03 dB mV +0.03 m/C FLASH MEMORY Endurance Data Retention TA = +25C Byte Writes Between Erase Operations Write Time, per Byte 20,000 Cycles 100 Years 2 50 s Page Erase Time 22 ms Mass Erase Time 22 ms www.maximintegrated.com Per 2 bytes if using SPI Cycles Maxim Integrated 11 71M6545T/71M6545HT Energy Meter ICs Electrical Characteristics (continued) (Limits are production tested at TA = +25C. Limits over the operating temperature range and relevant supply voltage range are guaranteed by design and characterization.) PARAMETER CONDITIONS MIN TYP MAX UNITS SPI Data-to-Clock Setup Time 10 ns Data Hold Time From Clock 10 ns Output Delay, Clock to Data 40 ns CS-to-Clock Setup Time 10 ns Hold Time, CS to Clock 15 ns Clock High Period 40 ns Clock Low Period 40 ns Clock Frequency (as a Multiple of CPU Frequency) 2.0 Space Between SPI Transactions MHz/MHz CPU Cycles 4.5 EEPROM INTERFACE I2C SCL Frequency 3-Wire Write Clock Frequency MPU clock = 4.9MHz, using interrupts 310 MPU clock = 4.9MHz, bit-banging DIO2-DIO3 100 MPU clock = 4.9MHz, PLL_FAST = 0 160 MPU clock = 4.9MHz, PLL_FAST = 1 490 kHz kHz RESET Reset Pulse Width (Note 1) Reset Pulse Fall Time (Note 1) 5 s 1 s 2255 Years INTERNAL CALENDAR Year Date Range 2000 Recommended External Components NAME FROM TO FUNCTION VALUE UNITS C1 VV3P3A GNDA Bypass capacitor for 3.3V supply 0.1 20% F C2 VV3P3D GNDD Bypass capacitor for 3.3V output 0.1 20% F 1.0 30% F 0.1 20% F 32.768 kHz 22 10% pF 22 10% pF CSYS VV3P3SYS GNDD Bypass capacitor for VV3P3SYS CVDD VDD GNDD Bypass capacitor for VDD XTAL XIN XOUT 32.768 kHz crystal; electrically similar to ECS .327-12.5-17X, Vishay XT26T or Suntsu SCP6- 32.768kHz TR (load capacitance 12.5pF) CXS (Note 2) XIN GNDA CXL (Note 2) XOUT GNDA Load capacitor values for crystal depend on crystal specifications and board parasitics. Nominal values are based on 3pF allowance for the sum of board capacitance and chip capacitance. Note 1: Parameter not tested in production, guaranteed by design to six-sigma. Note 2: If the capacitor values of CXS = 15pF and CXL = 10pF have already been installed, then changing the CXL value to 33pF and leaving CXS = 15pF would minimize rework. www.maximintegrated.com Maxim Integrated 12 71M6545T/71M6545HT Energy Meter ICs XIN GNDA VBAT_RTC VV3P3SYS IADC2 IADC3 IADC4 IADC5 IADC6 IADC7 GNDD ICE_E E_RXTX E_TCLK E_RST RX Pin Configuration 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 TOP VIEW XOUT 49 32 DIO55 GNDA 50 31 DIO0/WPULSE TEST 51 30 DIO1/VPULSE VADC10 (VC) 52 29 DIO2/SDCK VADC9 (VB) 53 28 DIO3/SDATA VADC8 (VA) 54 27 DIO4 VV3P3A 55 26 DIO5 IADC1 56 25 DIO6/XPULSE IADC0 57 24 DIO7/YPULSE VREF 58 23 DIO8/DI N.C. 59 22 DIO9 PB 60 21 DIO10 RESET 61 20 DIO11 TMUXOUT 62 19 DIO12 TMUX2OUT 63 18 DIO13 SPI_CKI 64 17 DIO14 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 SPI_DI SPI_DO SPI_CSZ VDD VV3P3D DIO29 DIO28 DIO25 DIO24 DIO23 DIO22 DIO21 DIO20 DIO19 TX GNDD 71M6545T 71M6545HT LQFP www.maximintegrated.com Maxim Integrated 13 71M6545T/71M6545HT Energy Meter ICs Pin Descriptions PIN NAME TYPE CIRCUIT FUNCTION POWER AND GROUND PINS 47, 50 GNDA P -- Analog Ground. This pin should be connected directly to the ground plane. 16, 38 GNDD P -- Digital Ground. This pin should be connected directly to the ground plane. 55 VV3P3A P -- Analog Power Supply. A 3.3V power supply should be connected to this pin. VV3P3A must be the same voltage as VV3P3SYS. 45 VV3P3SYS P -- System 3.3V supply. This pin should be connected to a 3.3V power supply. 5 VV3P3D O 13 Auxiliary Voltage Output of the Chip. In mission mode, this pin is connected to VV3P3SYS by the internal selection switch. In BRN mode, it is internally connected to VBAT. VV3P3D is floating in LCD and sleep mode. A 0.1F bypass capacitor to ground must be connected to this pin. 4 VDD O -- Output of the 2.5V Regulator. This pin is powered in MSN and BRN modes. A 0.1F bypass capacitor to ground should be connected to this pin. 46 VBAT_RTC P 12 RTC and Oscillator Power Supply. A battery or super capacitor is to be connected between VBAT and GNDD. If no battery is used, connect VBAT_ RTC to VV3P3SYS. I 6 Differential or Single-Ended Line Current Sense Inputs. These pins are voltage inputs to the internal A/D converter. Typically, they are connected to the outputs of current sensors. Unused pins must be tied to VV3P3A. Pins IADC2-IADC3, IADC4-IADC5 and IADC6-IADC7 may be configured for communication with the remote sensor interface (71M6x03). ANALOG PINS 57, 56 IADC0 IADC1 44, 43 IADC2 IADC3 42, 41 IADC4 IADC5 40, 39 IADC6 IADC7 54, 53, 52 VADC8 (VA), VADC9 (VB), VADC10 (VC) I 6 Line Voltage Sense Inputs. These pins are voltage inputs to the internal A/D converter. Typically, they are connected to the outputs of resistor-dividers. Unused pins must be tied to VV3P3A. 58 VREF O 9 Voltage Reference for the ADC. This pin should be left unconnected (floating). 48 XIN I 8 Crystal Inputs. A 32.768kHz crystal should be connected across these pins. Typically, a 22pF capacitor is also connected from XIN to GNDA and a 22pF capacitor is connected from XOUT to GNDA. It is important to minimize the capacitance between these pins. See the crystal manufacturer data sheet for details. If an external clock is used, a 150mVP-P clock signal should be applied to XIN, and XOUT should be left unconnected. 49 XOUT www.maximintegrated.com O Maxim Integrated 14 71M6545T/71M6545HT Energy Meter ICs Pin Descriptions (continued) PIN NAME TYPE CIRCUIT FUNCTION DIGITAL PINS 31 DIO0/WPULSE 30 DIO1/VPULSE 29 DIO2/SDCK 28 DIO3/SDATA 27 DIO4 26 DIO5 25 DIO6/XPULSE 24 DIO7/YPULSE 23 DIO8/DI I/O 3 Multiple-Use Pins. Alternative functions with proper selection of associated I/O RAM registers are: DIO0 = WPULSE DIO1 = VPULSE DIO2 = SDCK DIO3 = SDATA DIO6 = XPULSE DIO7 = YPULSE DIO8 = DI DIO16 = RX3 DIO17 = TX3 Unused pins must be configured as outputs or terminated to V3P3/GNDD. I/O 3 SPI Interface I/O 3 DIO I/O 1 Emulator Port Pins 22-17 DIO[9:14] 14-8 DIO[19:25] 7-6 DIO[28:29] 3 SPI_CSZ 2 SPI_DO 1 SPI_DI 64 SPI_CKI 32 DIO55 36 E_RXTX 34 E_RST 35 E_TCLK O 4 37 ICE_E I 2 O 4, 5 62 TMUXOUT 63 TMUX2OUT ICE Enable. For production units, this pin should be pulled to GND to disable the emulator port. Multiplexer/Clock Output 61 RESET I 2 Chip Reset. This input pin is used to reset the chip into a known state. For normal operation, this pin is pulled low. To reset the chip, this pin should be pulled high. This pin has an internal 30FA (nominal) current source pulldown. No external reset circuitry is necessary. 33 RX I 3 UART Input. If this pin is unused it must be terminated to VV3P3D or GNDD. 15 TX O 4 UART Output 51 TEST I 7 Enables Production Test. This pin must be grounded in normal operation. 60 PB I 3 Pushbutton Input. This pin must be at GNDD when not active or unused. A rising edge sets the WF_PB flag. It also causes the part to wake up if it is in SLP mode. PB does not have an internal pullup or pulldown resistor. 59 N.C. N.C. -- No Connection. Do not connect these pins. I = Input, O = Output, P = Power www.maximintegrated.com Maxim Integrated 15 71M6545T/71M6545HT V3P3D Energy Meter ICs V3P3D V3P3D 110k V3P3D DIGITAL INPUT PIN CMOS INPUT ANALOG INPUT PIN FROM INTERNAL REFERENCE TO MUX GNDA GNDA DIGITAL INPUT EQUIVALENT CIRCUIT TYPE 1: STANDARD DIGITAL INPUT OR PIN CONFIGURED AS DIO INPUT WITH INTERNAL PULL-UP VREF PIN ANALOG INPUT EQUIVALENT CIRCUIT TYPE 6: ADC INPUT VREF EQUIVALENT CIRCUIT TYPE 9: VREF V3P3D V3P3D V3P3D DIGITAL INPUT PIN CMOS INPUT 110k COMPARATOR INPUT PIN TO COMPARATOR GNDD FROM INTERNAL REFERENCE GNDD GNDA GNDD COMPARATOR INPUT EQUIVALENT CIRCUIT TYPE 7: COMPARATOR INPUT DIGITAL INPUT TYPE 2: PIN CONFIGURED AS DIO INPUT WITH INTERNAL PULL-UP V2P5 PIN V2P5 EQUIVALENT CIRCUIT TYPE 10: V2P5 V3P3D DIGITAL INPUT PIN CMOS INPUT TO OSCILLATOR OSCILLATOR PIN DIGITAL INPUT TYPE 3: STANDARD DIGITAL INPUT OR PIN CONFIGURED AS DIO INPUT POWER DOWN CIRCUITS GNDD GNDD GNDD VBAT PIN OSCILLATOR EQUIVALENT CIRCUIT TYPE 8: OSCILLATOR I/O VBAT EQUIVALENT CIRCUIT TYPE 12: VBAT POWER V3P3D V3P3D DIGITAL OUTPUT PIN CMOS OUTPUT GNDD DIGITAL OUTPUT EQUIVALENT CIRCUIT TYPE 4: STANDARD DIGITAL OUTPUT OR PIN CONFIGURED AS DIO OUTPUT FROM V3P3SYS FROM VBAT 10 40 V3P3D PIN V3P3D EQUIVALENT CIRCUIT TYPE 13: V3P3D Figure 1. I/O Equivalent Circuits www.maximintegrated.com Maxim Integrated 16 71M6545T/71M6545HT Energy Meter ICs Block Diagram VREF IADC0 IADC1 IADC2 IADC3 IADC4 IADC5 IADC6 IADC7 VADC8 VADC9 VADC10 GNDA VBIAS GNDA GNDD GNDD V3P3SYS V3P3A AD CONVERTER VBIAS V3P3A FIR MUX AND PREAMP VREF MUX V3P3D VREF CROSS MUX CTRL VOLTAGE REGULATOR CK32 XIN OSCILLATOR XOUT RTCLK (32kHz) 32kHz CK32 32kHz MCK PLL DIV ADC 4.9MHz CKADC 4.9MHz CKFIR VDD 22 2.5V TO LOGIC CK_4X CLOCK GEN MUX CKMPU_2x TEST CKCE 4.9MHz TEST MODE STRT CE 32-BIT COMPUTE ENGINE CE CONTROL MPU RAM 3.5KB WPULSE VARPULSE RTM 32 MEMORY SHARE CEDATA 0x000...0x2FF 0x0000...0x13FF 8 PROG 0x000...0x3FF RX SDCK SDOUT SDIN POWER FAULT DETECTION RTC RTCLK 8 MEMORY SHARE 8 CKMPU_2x WAKE FAULTZ 0x0000... 0xFFFF 16 FLASH 64KB EMULATOR PORT 3 VSTAT CONFIGURATION RAM (I/O RAM) 0x2000...0x20FF 8 PROGRAM 0x0000...0xFFFF MPU_RSTZ VBAT_RTC NON-VOLATILE CONFIGURATION RAM DATA 0x0000...0xFFFF VBIAS SPI_I/F DIO PINS PB EEPROM INTERFACE MPU (80515) UART0 TX DIGITAL I/O WPULSE VARPULSE I/O RAM XFER BUSY CE_BUSY 16 CKMPU 4.9MHz SPI MUX_SYNC RTM E_RXTX E_TCLK E_RST ICE_E RESET BAT TEST TEMP SENSOR CONFIGURATION PARAMETERS TEST MUX TEST MUX 2 TMUXOUT TMU2XOUT E_RXTX E_TCLK E_RST www.maximintegrated.com Maxim Integrated 17 71M6545T/71M6545HT Hardware Description Energy Meter ICs * A fully differential shunt resistor sensor input The 71M6545T/HT single-chip energy meter ICs integrate all primary functional blocks required to implement a solid-state residential electricity meter. Included on the chip are the following: * A preamplifier to optimize shunt current sensor performance * * An analog front-end (AFE) featuring a 22-bit secondorder sigma-delta ADC Isolated power circuitry obtains dc power from pulses sent by the 71M654xT * An independent 32-bit digital computation engine (CE) to implement DSP functions * An 8051-compatible microprocessor (MPU) which executes one instruction per clock cycle (80515) * A precision voltage reference (VREF) A temperature sensor for digital temperature compensation: In a typical application, the 32-bit compute engine (CE) of the 71M654xT sequentially processes the samples from the voltage inputs on analog input pins and from the external 71M6x03 isolated sensors and performs calculations to measure active energy (Wh) and reactive energy (VARh), as well as A2h, and V2h for four-quadrant metering. These measurements are then accessed by the MPU, processed further and output using the peripheral devices available to the MPU. * * Metrology digital temperature compensation (MPU) * Automatic RTC digital temperature compensation operational in all power states * RAM and flash memory * A real-time clock (RTC) * A variety of I/O pins * A power-failure interrupt * A zero-crossing interrupt * Selectable current sensor interfaces for locally-connected sensors as well as isolated sensors (i.e., using the 71M6x03 companion IC with a shunt resistor sensor) * Resistive shunt and current transformers are supported Resistive shunts and current transformer (CT) current sensors are supported. Resistive shunt current sensors may be connected directly to the 71M654xT device or isolated using a companion 71M6x03 isolator IC in order to implement a variety of metering configurations. An inexpensive, small pulse transformer is used to isolate the 71M6x03 isolated sensor from the 71M654xT. The 71M654xT performs digital communications bidirectionally with the 71M6x03 and also provides power to the 71M6x03 through the isolating pulse transformer. Isolated (remote) shunt current sensors are connected to the differential input of the 71M6x03. Included on the 71M6x03 companion isolator chip are: * Digital isolation communications interface * An analog front-end (AFE) * A precision voltage reference (VREF) A temperature sensor (for digital temperature compensation) * www.maximintegrated.com In addition to advanced measurement functions, the clock function allows the 71M6545T/HT to record time-of-use (TOU) metering information for multi-rate applications and to time-stamp tamper or other events. In addition to the temperature-trimmed ultra-precision voltage reference, the on-chip digital temperature compensation mechanism includes a temperature sensor and associated controls for correction of unwanted temperature effects on measurement and RTC accuracy, e.g., to meet the requirements of ANSI and IEC standards. Temperature-dependent external components such as crystal oscillator, resistive shunts, current transformers (CTs) and their corresponding signal conditioning circuits can be characterized and their correction factors can be programmed to produce electricity meters with exceptional accuracy over the industrial temperature range. See the Block Diagram. Analog Front-End (AFE) The AFE functions as a data acquisition system, controlled by the MPU. When used with locally connected sensors, as shown in Figure 2, the analog input signals (IADC0IADC7, VADC8-VADC10) are multiplexed to the ADC input and sampled by the ADC. The ADC output is decimated by the FIR filter and stored in CE RAM where it can be accessed and processed by the CE. When remote isolated sensors are connected to the 71M6545T/HT using 71M6x03 remote sensor interfaces, the input multiplexer is bypassed. Instead, the extracted modulator bit stream is passed directly to a dedicated decimation filter. The output of the decimation filter is then directly stored in the appropriate CE RAM location without making use of a multiplexer cycle. Maxim Integrated 18 71M6545T/71M6545HT Energy Meter ICs VREF IA IADC0 ADC CONVERTER VREF IADC1 IB VADC VREF FIR 22 CE RAM IADC2 IADC3 IC IADC4 IADC5 MUX 71M6545T/HT IN* IADC6 CT IADC7 VADC10 (VA) VADC10 (VB) VADC10 (VC) *IN = OPTIONAL NEUTRAL CURRENT Figure 2. 71M6545T/HT Operating with Local Sensors www.maximintegrated.com Maxim Integrated 19 71M6545T/71M6545HT Energy Meter ICs Signal Input Pins The 71M6545T/HT features eleven ADC inputs. IADC0-IADC7 are intended for use as current sensor inputs. These eight current sensor inputs can be configured as four single-ended inputs, or (more frequently) can be paired to form four differential inputs. For best performance, it is recommended to configure the current sensor inputs as differential inputs. The first differential input (IADC0-IADC1) features a preamplifier with a selectable gain of 1 or 8, and is intended for direct connection to a shunt resistor sensor, and can also be used with a current transformer (CT). The remaining differential pairs may be used with CTs, or may be enabled to interface to a remote 71M6x03 isolated current sensor providing isolation for a shunt resistor sensor using a low cost pulse transformer. The remaining inputs (VADC8-VADC10) are single-ended and sense line voltage. These single-ended inputs are referenced to the VV3P3A pin. All analog signal input pins measure voltage. In the case of shunt current sensors, currents are sensed as a voltage drop in the shunt resistor sensor. Referring to Figure 2, shunt sensors can be connected directly to the 71M654xT (referred to as a `local' shunt sensor) or connected through an isolated 71M6x03 (referred to as a `remote' shunt sensor) (Figure 3). In the case of current transformers, the current is measured as a voltage across a burden resistor that is connected to the secondary winding of the CT. Meanwhile, line voltages are sensed through resistive voltage dividers. VREF IN* IADC0 LOCAL SHUNT IADC1 ADC CONVERTER VREF MUX VADC8 (VA) VREF FIR VADC 22 VADC9 (VB) VADC10 (VC) IA INP REMOTE SHUNT SP IADC2 71M6x03 INN SN IADC3 DIGITAL ISOLATION INTERFACE 22 CE RAM IB INP REMOTE SHUNT SP IADC4 71M6x03 INN SN IADC5 INP SP IADC6 DIGITAL ISOLATION INTERFACE 22 DIGITAL ISOLATION INTERFACE 22 IC REMOTE SHUNT 71M6x03 INN SN IADC7 71M6545T/HT * IN = OPTIONAL NEUTRAL CURRENT Figure 3. 71M6545T/HT Operating with Remote Sensor for Neutral Current www.maximintegrated.com Maxim Integrated 20 71M6545T/71M6545HT Pins IADC0-IADC1 can be programmed individually to be differential or single-ended. For most applications IADC0IADC1 are configured as a differential input to work with a shunt or CT directly interfaced to the IADC0-IADC1 differential input with the appropriate external signal conditioning components. The performance of the IADC0-IADC1 pins can be enhanced by enabling a preamplifier with a fixed gain of 8. When the PRE_E bit = 1, IADC0-IADC1 become the inputs to the 8x preamplifier, and the output of this amplifier is supplied to the multiplexer. The 8x amplification is useful when current sensors with low sensitivity, such as shunt resistors, are used. With PRE_E set, the IADC0-IADC1 input signal amplitude is restricted to 31.25 mV peak. When shunt resistors are used as current sense elements on all current inputs, the IADC0-IADC1 pins are configured for differential mode to interface to a local shunt by setting the DIFFA_E control bit. Meanwhile, the IADC2-IADC7 pins are re-configured as digital balanced pair to communicate with a 71M6x03 isolated sensor interface by setting the RMT_E control bit. The 71M6x03 communicates with the 71M654xT using a bidirectional digital data stream through an isolating low-cost pulse transformer. The 71M654xT also supplies power to the 71M6x03 through the isolating transformer. When using current transformers the IADC2-IADC7 pins are configured as local analog inputs (RMT_E = 0). The IADC0-IADC1 pins cannot be configured as a remote sensor interface. Input Multiplexer When operating with local sensors, the input multiplexer sequentially applies the input signals from the analog input pins to the input of the ADC. One complete sampling sequence is called a multiplexer frame. The multiplexer of the 71M6545T/HT can select up to seven input signals (three voltage inputs and four current inputs) per multiplexer frame. The multiplexer always starts at state 1 and proceeds until as many states as determined by MUX_DIV[3:0] have been converted. The 71M6545T/HT requires CE code that is written for the specific application. Moreover, each CE code requires specific AFE and MUX settings in order to function properly. Contact Maxim Integrated for specific information about alternative CE codes. www.maximintegrated.com Energy Meter ICs For a polyphase configuration with neutral current sensing using shunt resistor current sensors and the 71M6xx3 isolated sensors, as shown in Figure 3, the IADC0-IADC1 input must be configured as a differential input, to be connected to a local shunt. The local shunt connected to the IADC0-IADC1 input is used to sense the Neutral current. The voltage sensors (VADC8-VADC10) are also directly connected to the 71M6545T/HT and are also routed though the multiplexer. Meanwhile, the IADC2-IADC7 current inputs are configured as remote sensor digital interfaces and the corresponding samples are not routed through the multiplexer. For a polyphase configuration with optional neutral current sensing using Current Transformer (CTs) sensors, all four current sensor inputs must be configured as differential inputs. IADC2-IADC3 is connected to phase A, IADC4IADC5 is connected to phase B, and IADC6-IADC7 is connected to phase C. The IADC0-IADC1 current sensor input is optionally used to sense the Neutral current for anti-tampering purposes. The voltage sensors (VADC8-VADC10), typically resistive dividers, are directly connected to the 71M6545T/HT. No 71M6xx3 isolated sensors are used in this configuration and all signals are routed though the multiplexer. The multiplexer sequence shown in Figure 4 corresponds to the configuration shown in Figure 3. The frame duration is 13 CK32 cycles (where CK32 = 32,768Hz), therefore, the resulting sample rate is 32,768Hz/13 = 2,520.6Hz. Note that Figure 4 only shows the currents that pass through the 71M6545T/HT multiplexer, and does not show the currents that are copied directly into CE RAM from the remote sensors (see Figure 3), which are sampled during the second half of the multiplexer frame. The two unused conversion slots shown are necessary to produce the desired 2,520.6Hz sample rate. The multiplexer sequence shown in Figure 5 corresponds to the CT configuration shown in Figure 2. Since in this case all current sensors are locally connected to the 71M6545T/HT, all currents are routed through the multiplexer, as seen in Figure 2. For this multiplexer sequence, the frame duration is 15 CK32 cycles (where CK32 = 32,768Hz), therefore, the resulting sample rate is 32,768Hz/15 = 2,184.5Hz. Maxim Integrated 21 71M6545T/71M6545HT Energy Meter ICs Delay Compensation for current) controlled to sample simultaneously. Our Single Converter Technology, however, exploits the 32-bit signal processing capability of its CE to implement "constant delay" allpass filters. The allpass filter corrects for the conversion time difference between the voltage and the corresponding current samples that are obtained with a single multiplexed A/D converter. When measuring the energy of a phase (i.e., Wh and VARh) in a service, the voltage and current for that phase must be sampled at the same instant. Otherwise, the phase difference, , introduces errors. = t delay T 360= t delay f 360 The "constant delay" allpass filter provides a broad-band delay 360 - , which is precisely matched to the differ ence in sample time between the voltage and the current of a given phase. This digital filter does not affect the amplitude of the signal, but provides a precisely controlled phase response. Where f is the frequency of the input signal, T = 1/f and tdelay is the sampling delay between current and voltage. Traditionally, sampling is accomplished by using two A/D converters per phase (one for voltage and the other one MULTIPLEXER FRAME SETTLE MUX_DIV[3:0] = 6 CONVERSIONS CK32 MUX STATE S 0 1 2 3 4 5 IN UNUSED UNUSED VA VB VC S CROSS MUX_SYNC Figure 4. Multiplexer Sequence with Neutral Channel and Remote Sensors MULTIPLEXER FRAME SETTLE MUX_DIV[3:0] = 7 CONVERSIONS CK32 MUX STATE S 0 1 2 3 4 5 6 IA VA IB VB IC VC IN S CROSS MUX_SYNC Figure 5. Multiplexer Sequence with Neutral Channel and Current Transformers www.maximintegrated.com Maxim Integrated 22 71M6545T/71M6545HT Energy Meter ICs Table 1. ADC Input Configuration PIN IADC0 IADC1 IADC2 IADC3 IADC4 IADC5 IADC6 IADC7 REQUIRED SETTING COMMENT DIFFx_E = 1 Differential mode must be selected with DIFFx_E = 1. The ADC results are stored in ADC0 and ADC1 is not disturbed. DIFFx_E = 1 or For locally connected sensors the differential input must be enabled. RMT_E = 1 For the remote sensor RMT_E must be set. ADC results are stored in ADC2 and ADC3 is not disturbed. DIFFx_E = 1 or For locally connected sensors the differential input must be enabled. RMT_E = 1 For the remote sensor RMT_E must be set. ADC results are stored in ADC4 and ADC5 is not disturbed. DIFFx_E = 1 or For locally connected sensors the differential input must be enabled. RMT_E = 1 For the remote sensor RMT_E must be set. ADC results are stored in ADC6 and ADC7 is not disturbed. VADC8 -- Phase A voltage. Single ended mode only. ADC result stored in ADC8. VADC9 -- Phase B voltage. Single ended mode only. ADC result stored in ADC9. VADC10 -- Phase A voltage. Single ended mode only. ADC result stored in ADC10. The recommended ADC multiplexer sequence samples the current first, immediately followed by sampling of the corresponding phase voltage, thus the voltage is delayed by a phase angle relative to the current. The delay compensation implemented in the CE aligns the voltage samples with their corresponding current samples by first delaying the current samples by one full sample interval (i.e., 360), then routing the voltage samples through the allpass filter, thus delaying the voltage samples by 360o - , resulting in the residual phase error between the current and its corresponding voltage of B - . The residual phase error is negligible, and is typically less than 1.5 milli-degrees at 100Hz, thus it does not contribute to errors in the energy measurements. When using remote sensors, the CE performs the same delay compensation described above to align each voltage sample with its corresponding current sample. Even though the remote current samples do not pass through the 71M654xT multiplexer, their timing relationship to their corresponding voltages is fixed and precisely known. ADC Preamplifier The ADC preamplifier is a low-noise differential amplifier with a fixed gain of 8 available only on the IADC0IADC1 sensor input pins. A gain of 8 is enabled by setting PRE_E = 1. When disabled, the supply current of the preamplifier is < 10 nA and the gain is unity. With proper settings of the PRE_E and DIFFA_E (I/O RAM 0x210C[4]) bits, the preamplifier can be used whether or not differential mode is selected. For best performance, the differential www.maximintegrated.com mode is recommended. In order to save power, the bias current of the preamplifier and ADC is adjusted according to the ADC_DIV control bit (I/O RAM 0x2200[5]). Analog-to-Digital Converter (ADC) A single 2nd-order delta-sigma ADC digitizes the voltage and current inputs to the device. The resolution of the ADC, including the sign bit, is 21 bits (FIR_LEN[1:0] = 1), or 22 bits (FIR_LEN[1:0] = 2). Initiation of each ADC conversion is controlled by MUX_ CTRL internal circuit. At the end of each ADC conversion, the FIR filter output data is stored into the CE RAM location determined by the multiplexer selection. FIR data is stored LSB justified, but shifted left 9 bits. FIR Filter The finite impulse response filter is an integral part of the ADC and it is optimized for use with the multiplexer. The purpose of the FIR filter is to decimate the ADC output to the desired resolution. At the end of each ADC conversion, the output data is stored into the fixed CE RAM location determined by the multiplexer selection. Voltage References A bandgap circuit provides the reference voltage to the ADC. The VREF band-gap amplifier is chopper-stabilized to remove the dc offset voltage. This offset voltage is the most significant long-term drift mechanism in voltage reference circuits. Maxim Integrated 23 71M6545T/71M6545HT Energy Meter ICs Isolated Sensor Interface Digital Computation Engine (CE) Nonisolating sensors, such as shunt resistors, can be connected to the inputs of the 71M654xT through a combination of a pulse transformer and a 71M6x03 isolated sensor interface. The 71M6x03 receives power directly from the 71M654xT through a pulse transformer and does not require a dedicated power supply circuit. The 71M6x03 establishes 2-way communication with the 71M654xT, supplying current samples and auxiliary information such as sensor temperature through a serial data stream. The CE, a dedicated 32-bit signal processor, performs the precision computations necessary to accurately measure energy. The CE calculations and processes include: Up to three 71M6x03 isolated sensors can be supported by the 71M6545T/HT. When a remote sensor interface is enabled, the two analog current inputs become reconfigured as a digital remote sensor interface. Each 71M6x03 isolated sensor consists of the following building blocks: * Power supply for power pulses received from the 71M654xT * Digital communications interface * Shunt signal preamplifier * Delta-sigma ADC converter with precision bandgap reference (chopping amplifier) * Temperature sensor * Fuse system containing part-specific information During an ordinary multiplexer cycle, the 71M654xT internally determines which other channels are enabled. At the same time, it decimates the modulator output from the 71M6x03 isolated sensors. Each result is written to CE RAM during one of its CE access time slots. The ADC of the 71M6x03 derives its timing from the power pulses generated by the 71M654xT and as a result, operates its ADC slaved to the frequency of the power pulses. The generation of power pulses, as well as the communication protocol between the 71M654xT and 71M6x03 isolated sensor is automatic and transparent to the user. The 71M654xT can read data and status from, and can write control information to the 71M6x03 isolated sensor. With hardware and trim-related information on each connected 71M6x03 isolated sensor available to the 71M6545T/HT, the MPU can implement temperature compensation of the energy measurement based on the individual temperature characteristics of the 71M6x03 isolated sensor. www.maximintegrated.com * Multiplication of each current sample with its associated voltage sample to obtain the energy per sample (when multiplied with the constant sample time). * Frequency-insensitive delay cancellation on all four channels (to compensate for the delay between samples caused by the multiplexing scheme). * 90 phase shifter (for VAR calculations). * Pulse generation. * Monitoring of the input signal frequency (for frequency and phase information). * Monitoring of the input signal amplitude (for sag detection). * Scaling of the processed samples based on calibration coefficients. * Scaling of samples based on temperature compensation information. Meter Equations The 71M6545T/HT provides hardware assistance to the CE in order to support various meter equations. The compute engine firmware for industrial configurations can implement the equations listed in Table 2. EQU[2:0] specifies the equation to be used based on the meter configuration and on the number of phases used for metering. Real-Time Monitor The CE contains a real-time monitor (RTM), which can be programmed to monitor four selectable XRAM locations at full sample rate. The four monitored locations are serially output to the TMUXOUT pin via the digital output multiplexer at the beginning of each CE code pass. The RTM can be enabled and disabled with control bit RTM_E. The RTM output is clocked by CKTEST. Each RTM word is clocked out in 35 CKCE cycles (1 CKCE cycle is equivalent to 203ns) and contains a leading flag bit. Maxim Integrated 24 71M6545T/71M6545HT Energy Meter ICs Table 2. Inputs Selected in Multiplexer Cycles EQU DESCRIPTION Wh AND VARh FORMULA ELEMENT 0 ELEMENT 1 ELEMENT 2 RECOMMENDED MULTIPLEXER SEQUENCE 2 2-element, 3W 3ph Delta VA x IA VA x IB N/A IA VA IB VB 3 2-element, 4W 3ph Delta VA (IA-IB)/2 VC x IC N/A IA VA IB VB IC VC 4 2-element, 4W 3ph Wye VA (IA-IB)/2 VB (IC-IB)/2 N/A IA VA IB VB IC VC 5 3-element, 4W 3ph Wye VA x IA VB x IA VC x IC IA VA IB VB IC VC (ID) Note: Only EQU = 5 is supported by currently available CE code versions for the 71M6545T/HT. Contact your Maxim Integrated representative for CE codes that support equations 2, 3, and 4. Pulse Generators The 71M6545T/HT provides four pulse generators, VPULSE, WPULSE, XPULSE and YPULSE, as well as hardware support for the VPULSE and WPULSE pulse generators. The pulse generators can be used to output CE status indicators (for example, voltage sag) to DIO pins. All pulses can be configured to generate interrupts to the MPU. The polarity of the pulses may be inverted with control bit PLS_INV. When this bit is set, the pulses are active high, rather than the more usual active low. PLS_INV inverts all four pulse outputs. The function of each pulse generator is determined by the CE code and the MPU code must configure the corresponding pulse outputs in agreement with the CE code. For example, standard CE code produces a mains zerocrossing pulse on XPULSE and a SAG pulse on YPULSE. A common use of the zero-crossing pulses is to generate interrupt in order to drive real-time clock software in places where the mains frequency is sufficiently accurate to do so and also to adjust for crystal aging. A common use for the SAG pulse is to generate an interrupt that alerts the MPU when mains power is about to fail, so that the MPU code can store accumulated energy and other data to EEPROM before the VV3P3SYS supply voltage actually drops. tional to reactive energy. During each CE code pass the hardware stores exported WPULSE and VPULSE sign bits in an 8-bit FIFO and sends the buffered sign bits to the output pin at a specified, known interval. This permits the CE code to calculate the VPULSE and WPULSE outputs at the beginning of its code pass and to rely on hardware to spread them over the multiplexer frame. 80515 MPU Core The 71M6545T/HT includes an 80515 MPU (8-bit, 8051-compatible) that processes most instructions in one clock cycle: a 4.9MHz clock results in a processing throughput of 4.9 MIPS. The 80515 architecture eliminates redundant bus states and implements parallel execution of fetch and execution phases. Normally, a machine cycle is aligned with a memory fetch, therefore, most of the 1-byte instructions are performed in a single machine cycle (MPU clock cycle). This leads to an 8x average performance improvement (in terms of MIPS) over the 8051 device running at the same clock frequency. The CKMPU frequency is a function of the MCK clock (19.6608MHz) divided by the MPU clock divider which is set in the I/O RAM control field MPU_DIV[2:0]. Actual processor clocking speed can be adjusted to the total processing demand of the application (metering calculations, AMR management, memory management, and I/O management) using MPU_DIV[2:0], as shown in Table 3. XPULSE and YPULSE Memory Organization and Addressing Pulses generated by the CE may be exported to the XPULSE and YPULSE pulse output pins. Pins SEGDIO6 and SEGDIO7 are used for these pulses, respectively. Generally, the XPULSE and YPULSE outputs can be updated once on each pass of the CE code. The 80515 MPU core incorporates the Harvard architecture with separate code and data spaces. Memory organization in the 80515 is similar to that of the industry standard 8051. There are three memory areas: program memory (flash, shared by MPU and CE), external RAM (data RAM, shared by the CE and MPU, configuration or I/O RAM), and internal data memory (internal RAM). VPULSE and WPULSE By default, WPULSE emits a pulse proportional to real energy consumed, and VPULSE emits a pulse propor- www.maximintegrated.com Maxim Integrated 25 71M6545T/71M6545HT Energy Meter ICs Program Memory The 80515 can address up to 64KB of program memory space (0x0000 to 0xFFFF). Program memory is read when the MPU fetches instructions or performs a MOVC operation. After reset, the MPU starts program execution from program memory location 0x0000. The lower part of the program memory includes reset and interrupt vectors. The interrupt vectors are spaced at 8-byte intervals, starting from code space location 0x0003. MPU External Data Memory (XRAM) Both internal and external memory is physically located on the 71M654xT device. The external memory referred in this documentation is only external to the 80515 MPU core. 3KB of RAM starting at address 0x0000 is shared by the CE and MPU. The CE normally uses the first 1KB, leaving 2KB for the MPU. Different versions of the CE code use varying amounts. Consult the documentation for the specific code version being used for the exact limit. MOVX Addressing There are two types of instructions differing in whether they provide an 8-bit or 16-bit indirect address to the external data RAM: * MOVX A,@Ri: The contents of R0 or R1 in the current register bank provide the eight low-order address bits with the eight high-order bits specified by the PDATA SFR. This method allows the user paged access (256 pages of 256 bytes each) to all ranges of the external data RAM. * MOVX A,@DPTR: The data pointer generates a 16-bit address. This form is faster and more efficient when accessing very large data arrays (up to 64KB) since no additional instructions are needed to set up the eight high ordered bits of the address. Table 3. CKMPU Clock Frequencies MPU_DIV [2:0] CKMPU FREQUENCY 000 4.9152MHz 001 2.4576MHz 010 1.2288MHz 011 614.4kHz 100 101 307.2kHz 110 111 It is possible to mix the two MOVX types. This provides the user with four separate data pointers, two with direct access and two with paged access, to the entire external memory range. Table 4. Memory Map ADDRESS (hex) MEMORY TECHNOLOGY MEMORY TYPE NAME MEMORY SIZE (BYTES) MPU program and nonvolatile data 64K CE program (on 1KB boundary) 3K max 0000-FFFF (64K) Flash Memory 0000-0BFF Static RAM Volatile External RAM (XRAM) Shared by CE and MPU 5K 2000-27FF Static RAM Volatile Configuration RAM (I/O RAM) Hardware control 2K 2800-287F Static RAM Nonvolatile (battery) Configuration RAM (I/O RAM) Battery-buffered memory 128 0000-00FF Static RAM Volatile Part of 80515 Core 256 www.maximintegrated.com Nonvolatile Program memory for MPU and CE TYPICAL USAGE Internal RAM Maxim Integrated 26 71M6545T/71M6545HT Energy Meter ICs Dual Data Pointer The Dual Data Pointer accelerates the block moves of data. The standard DPTR is a 16-bit register that is used to address external memory or peripherals. In the 80515 core, the standard data pointer is called DPTR, the second data pointer is called DPTR1. The data pointer select bit, located in the LSB of the DPS register, chooses the active pointer. DPTR is selected when DPS[0] = 0 and DPTR1 is selected when DPS[0] = 1. The user switches between pointers by toggling the LSB of the DPS register. The values in the data pointers are not affected by the LSB of the DPS register. All DPTR related instructions use the currently selected DPTR for any activity. An alternative data pointer is available in the form of the PDATA register (SFR 0xBF), sometimes referred to as USR2). It defines the high byte of a 16-bit address when reading or writing XDATA with the instruction MOVX A,@ Ri or MOVX @Ri,A. Internal Data Memory Map and Access The Internal data memory provides 256 bytes (0x00 to 0xFF) of data memory. The internal data memory address is always 1 byte wide. The Special Function Registers (SFR) occupy the upper 128 bytes. The SFR area of internal data memory is available only by direct addressing. Indirect addressing of this area accesses the upper 128 bytes of Internal RAM. The lower 128 bytes contain working registers and bit addressable memory. The lower 32 bytes form four banks of eight registers (R0-R7). Two bits on the program memory status word (PSW, SFR 0xD0) select which bank is in use. The next 16 bytes form a block of bit address- able memory space at addresses 0x00-0x7F. All of the bytes in the lower 128 bytes are accessible through direct or indirect addressing. Special Function Registers Only a few addresses in the SFR memory space are occupied; other addresses are unim plemented. A read access to unimplemented addresses returns undefined data, while a write access has no effect. SFRs specific to the 71M654xT are shown in bold print on a shaded field. The registers at 0x80, 0x88, 0x90, etc., are bit addressable, all others are byte addressable. Timers and Counters The 71M6545T/HT contains two 16-bit timer/counter registers: Timer 0 and Timer 1. These registers can be configured for counter or timer operations. In timer mode, the register is incremented every machine cycle, i.e., it counts up once for every 12 periods of the MPU clock. In counter mode, the register is incremented when the falling edge is observed at the corresponding input signal T0 or T1 (T0 and T1 are the timer gating inputs derived from certain DIO pins, see 2.5.8 Digital I/O). Since it takes 2 machine cycles to recognize a 1-to-0 event, the maximum input count rate is 1/2 of the clock frequency (CKMPU). There are no restrictions on the duty cycle, however to ensure proper recognition of the 0 or 1 state, an input should be stable for at least 1 machine cycle. Four operating modes can be selected for Timer 0 and Timer 1. The TMOD register is used to select the appropriate mode. The timer/counter operation is controlled by the TCON register. Bits TR1 and TR0 in the TCON register start their associated timers when set. Table 5. Internal Data Memory Map ADDRESS RANGE DIRECT ADDRESSING 0x80 0xFF Special Function Registers (SFRs) 0x30 0x7F Byte addressable area 0x20 0x2F Bit addressable area 0x00 0x1F Register banks R0...R7 www.maximintegrated.com INDIRECT ADDRESSING RAM Maxim Integrated 27 71M6545T/71M6545HT Energy Meter ICs Table 6. Special Function Register Map HEX/ BIN BIT ADDRESSABLE BYTE ADDRESSABLE X010 X011 X100 X101 RCMD SPI_CMD X110 X111 BIN/ HEX X000 X001 F8 INTBITS VSTAT F0 B F7 E8 IFLAGS EF FF E0 A E7 D8 WDCON DF D0 PSW D7 C8 T2CON CF C0 IRCON B8 IEN1 B0 P3 (DIO12:15) C7 IP1 A8 IEN0 A0 P2 (DIO8:11) 98 S0CON S0RELH S1RELH FLSH_CTL IP0 PDATA BF FLSH_ PGADR B7 S0RELL AF A7 S0BUF IEN2 S1CON S1BUF S1RELL EEDATA EECTRL FLH_ ERASE 90 P1(DIO4:7) 88 TCON TMOD TL0 TL1 TH0 TH1 80 P0 (DIO0:3) SP DPL DPH DPL1 DPH1 DPS 9F 97 CKCON 8F PCON 87 Table 7. Generic 80515 SFRs: Location and Reset Values NAME ADDRESS RESET VALUE DESCRIPTION P0 0x80 0xFF Port 0 SP 0x81 0x07 Stack Pointer DPL 0x82 0x00 Data Pointer Low 0 DPH 0x83 0x00 Data Pointer High 0 DPL1 0x84 0x00 Data Pointer Low 1 DPH1 0x85 0x00 Data Pointer High 1 PCON 0x87 0x00 UART Speed Control TCON 0x88 0x00 Timer/Counter Control TMOD 0x89 0x00 Timer Mode Control TL0 0x8A 0x00 Timer 0, low byte TL1 0x8B 0x00 Timer 1, high byte TH0 0x8C 0x00 Timer 0, low byte TH1 0x8D 0x00 Timer 1, high byte CKCON 0x8E 0x01 Clock Control (Stretch = 1) P1 0x90 0xFF Port 1 DPS 0x92 0x00 Data Pointer select Register S0CON 0x98 0x00 Serial Port 0, Control Register S0BUF 0x99 0x00 Serial Port 0, Data Buffer IEN2 0x9A 0x00 Interrupt Enable Register 2 S1CON 0x9B 0x00 Serial Port 1, Control Register www.maximintegrated.com Maxim Integrated 28 71M6545T/71M6545HT Energy Meter ICs Table 7. Generic 80515 SFRs - Location and Reset Values (continued) S1BUF 0x9C 0x00 NAME ADDRESS RESET VALUE Serial Port 1, Data Buffer S1RELL 0x9D 0x00 Serial Port 1, Reload Register, low byte P2 0xA0 0xFF Port 2 IEN0 0xA8 0x00 Interrupt Enable Register 0 IP0 0xA9 0x00 Interrupt Priority Register 0 S0RELL 0xAA 0xD9 Serial Port 0, Reload Register, low byte P3 0xB0 0xFF Port 3 IEN1 0xB8 0x00 Interrupt Enable Register 1 IP1 0xB9 0x00 Interrupt Priority Register 1 S0RELH 0xBA 0x03 Serial Port 0, Reload Register, high byte S1RELH 0xBB 0x03 Serial Port 1, Reload Register, high byte DESCRIPTION PDATA 0xBF 0x00 High address byte for MOVX@Ri - also called USR2 IRCON 0xC0 0x00 Interrupt Request Control Register T2CON 0xC8 0x00 Polarity for INT2 and INT3 PSW 0xD0 0x00 Program Status Word WDCON 0xD8 0x00 Baud Rate Control Register (only WDCON[7] bit used) A 0xE0 0x00 Accumulator B 0xF0 0x00 B Register Table 8. Timers/Counters Mode Description M1 M0 MODE FUNCTION 0 0 Mode 0 13-bit Counter/Timer mode with 5 lower bits in the TL0 or TL1 register and the remaining 8 bits in the TH0 or TH1 register (for Timer 0 and Timer 1, respectively). The 3 high order bits of TL0 and TL1 are held at zero. 0 1 Mode 1 16-bit Counter/Timer mode. 1 0 Mode 2 8-bit auto-reload Counter/Timer. The reload value is kept in TH0 or TH1, while TL0 or TL1 is incremented every machine cycle. When TLx overflows, a value from THx is copied to TLx. 1 1 Mode 3 If Timer 1 M1 and M0 bits are set to 1, Timer 1 stops. If Timer 0 M1 and M0 bits are set to 1, Timer 0 acts as two independent 8-bit Timer/Counters. Interrupts Interrupt Overview The 80515 provides 11 interrupt sources with four priority levels. Each source has its own interrupt request flag(s) located in a special function register (TCON, IRCON, and SCON). Each interrupt requested by the corresponding interrupt flag can be individually enabled or disabled by the interrupt enable bits in the IEN0, IEN1, and IEN2. When an interrupt occurs, the MPU vectors to the predetermined address. Once the interrupt service has begun, it can be interrupted only by a higher priority interrupt. The interrupt service is terminated by a return from interrupt instruction (RETI). When a RETI instruction is executed, the processor returns to the instruction that would have been next when the interrupt occurred. Referring to Figure 12, interrupt sources can originate from within the 80515 MPU core (referred to as Internal Sources) or can originate from other parts of the 71M654xT SoC (referred to as External Sources). There are seven external interrupt sources, (EX0-EX6). www.maximintegrated.com When the interrupt condition occurs, the processor also indicates this by setting a flag bit. This bit is set regardless of whether the interrupt is enabled or disabled. Each interrupt flag is sampled once per machine cycle, and then Maxim Integrated 29 71M6545T/71M6545HT Energy Meter ICs samples are polled by the hardware. If the sample indicates a pending interrupt when the interrupt is enabled, then the interrupt request flag is set. On the next instruction cycle, the interrupt is acknowledged by hardware forcing an LCALL to the appropriate vector address, if the following conditions are met: * No interrupt of equal or higher priority is already in progress. * An instruction is currently being executed and is not completed. * The instruction in progress is not RETI or any write access to the registers IEN0, IEN1, IEN2, IP0 or IP1. The following SFR registers control the interrupt functions: On-Chip Resources Flash Memory The device includes 64KB of on-chip flash memory. The flash memory primarily contains MPU and CE program code. It also contains images of the CE RAM and I/O RAM. On power-up, before enabling the CE, the MPU copies these images to their respective locations. Flash space allocated for the CE program is limited to 4096 16-bit words (8KB). The CE program must begin on a 1KB boundary of the flash address space. The CE_LCTN[5:0] field defines where in flash the CE code resides. The address of the CE program is 0bXXXX XX00 0000 0000, where XXXX XX represents one of the 64 1KB pages at which the CE program begins. * The interrupt enable registers: IEN0, IEN1 and IEN2. * The Timer/Counter control registers, TCON and T2CON. Flash memory can be accessed by the MPU and the CE for reading, and by the SPI interface for reading or writing. * The interrupt request register, IRCON. MPU/CE RAM * The interrupt priority registers: IP0 and IP1. The 71M6545T/HT includes 5KB of static RAM memory on-chip (XRAM) plus 256 bytes of internal RAM in the MPU core. The static RAM is used for data storage for both MPU and CE operations. External MPU Interrupts The seven external interrupts are the interrupts external to the 80515 core, i.e., signals that originate in other parts of the 71M654xT, for example the CE, DIO, RTC, or EEPROM interface. The polarity of interrupts 2 and 3 is programmable in the MPU via the I3FR and I2FR bits in T2CON (SFR 0xC8). Interrupts 2 and 3 should be programmed for falling sensitivity (I3FR = I2FR = 0). The generic 8051 MPU literature states that interrupts 4 through 6 are defined as rising-edge sensitive. Thus, the hardware signals attached to interrupts 5 and 6 are inverted to achieve the edge polarity shown in Table 9. I/O RAM The I/O RAM can be seen as a series of hardware registers that control basic hardware functions. I/O RAM address space starts at 0x2000. The 71M6545T/HT includes 128 bytes NV RAM memory on-chip in the I/O RAM address space (addresses 0x2800 to 0x287F). This memory section is supported by the voltage applied at VBAT_RTC and the data in it are preserved in BRN, LCD, and SLP modes as long as the voltage at VBAT_RTC is within specification. External interrupt 0 and 1 can be mapped to pins on the device using DIO resource maps. Table 9. External MPU Interrupts EXTERNAL INTERRUPT CONNECTION POLARITY FLAG RESET 0 Digital I/O (IE0) Programmable Automatic 1 Digital I/O (IE1) Programmable Automatic 2 CE_PULSE (IE_XPULSE, IE_YPULSE, IE_WPLUSE, IE_VPULSE) Rising Manual 3 CE_BUSY (IE3) Falling Automatic 4 VSTAT (VSTAT[2:0] changed) (IE4) Rising Automatic 5 EEPROM busy (falling), SPI (rising) (IE_EEX, IE_SPI) -- Manual 6 XFER_BUSY (falling), RTC_1SEC, RTC_1MIN, RTC_T, TC_TEMP (IE_XFER, IE_RTC1S, IE_RTC1M, IE_RTCT) Falling Manual www.maximintegrated.com Maxim Integrated 30 71M6545T/71M6545HT Crystal Oscillator The oscillator drives a standard 32.768kHz tuning-fork crystal. This type of crystal is accurate and does not require a high-current oscillator circuit. The oscillator power dissipation is very low to maximize the lifetime of the VBAT_RTC battery. Oscillator calibration can improve the accuracy of both the RTC and metering. PLL Timing for the device is derived from the 32,768Hz crystal oscillator. The oscillator output is routed to a phase-locked loop (PLL). The PLL multiplies the crystal frequency by 600 to produce a stable 19.6608MHz clock frequency. This is the master clock (MCK), and all onchip timing, except for the RTC clock, is derived from MCK. The master clock can operate at either 19.66MHz or 6.29MHz depending on the PLL_FAST bit. The MPU clock frequency CKMPU is determined by another divider controlled by the I/O RAM control field MPU_DIV[2:0] and can be set to MCK x 2-(MPU_DIV+2) , where MPU_DIV[2:0] may vary from 0 to 4. The 71M654xT VV3P3SYS supply current is reduced by reducing the MPU clock frequency. When the ICE_E pin is high, the circuit also generates the 9.83MHz clock for use by the emulator. The two general-purpose counter/timers contained in the MPU are clocked by CKMPU. The PLL is only turned off in SLP mode. When the part is waking up from SLP mode, the PLL is turned on in 6.29MHz mode, and the PLL frequency is not be accurate until the PLL_OK flag becomes active. Due to potential overshoot, the MPU should not change the value of PLL_FAST until PLL_OK is true. Real-Time Clock (RTC) The real-time clock is driven directly by the crystal oscillator and is powered by either the VV3P3SYS pin or the VBAT_RTC pin, depending on the V3OK internal bit. The RTC consists of a counter chain and a set of output registers. The counter chain consists of registers for seconds, minutes, hours, day of week, day of month, month, and year. The chain registers are supported by a shadow register that facilitates read and write operations. RTC Trimming The RTC accuracy can be trimmed by means of a digital trimming mechanism that affects only the RTC. Either or both of these adjustment mechanisms can be used to trim the RTC. www.maximintegrated.com Energy Meter ICs The 71M6545T/HT can also be configured to regularly measure die temperature, including in SLP mode and while the MPU is halted. If enabled, the temperature information is automatically used to correct for the temperature variation of the crystal. A quadratic equation is used to compute the temperature correction factors. The temperature is passed both to the quadratic calculation block and to a range check block. If the temperature exceeds the limits established in the SMIN, SMAX and SFILT registers when a range checking is enabled, a WAKE or an INTERRUPT event is posted. The quadratic calculation block computes the position on the inverse parabolic curve that is characteristic for tuning fork crystals based on the known and T0 values for the crystal (these are published by the crystal manufacturer and are relatively consistent for a particular crystal type). Finally, the absolute frequency error is added or subtracted from the computed value, and the final result is used to compensate the frequency of the crystal. RTC Interrupts The RTC generates interrupts each second and each minute. These interrupts are called RTC_1SEC and RTC_1MIN. In addition, the RTC functions as an alarm clock by generating an interrupt when the minutes and hours registers both equal their respective target counts as defined in the alarm registers. The alarm clock interrupt is called RTC_T. All three interrupts appear in the MPU's external interrupt 6. Temperature Sensor The 71M654xT includes an on-chip temperature sensor for determining the temperature of its bandgap reference. The primary use of the temperature data is to determine the magnitude of compensation required to offset the thermal drift in the system for the compensation of current, voltage and energy measurement and the RTC. See the Metrology Temperature Compensation. The 71M654xT uses a dual-slope temperature measurement technique that is operational in SLP mode, as well as BRN and MSN modes. This means that the temperature sensor can be used to compensate for the frequency variation of the crystal, even in SLP mode while the MPU is halted. In MSN and BRN modes, the temperature sensor is awakened on command from the MPU by setting the TEMP_START control bit. The MPU must wait for the TEMP_START bit to clear before reading STEMP[15:0] and before setting the TEMP_START bit once again. Maxim Integrated 31 71M6545T/71M6545HT Energy Meter ICs In SLP mode, it is awakened at a regular rate set by TEMP_PER[2:0]. * DIO2/SDCK, DIO3/SDATA (2 pins) The result of the temperature measurement can be read from STEMP[15:0]. Typically, only eleven bits are significant, the remaining high-order bits reflecting the sign of the temperature relative to 0C. * DIO6/XPULSE, DIO7/YPULSE (2 pins) * DIO8/DI (1 pin) * DIO26, DIO27 (2 pins) Battery Monitor The 71M654xT temperature measurement circuit can also monitor the batteries at the VBAT and VBAT_RTC pins. The battery to be tested (i.e., VBAT or VBAT_RTC pin) is selected by TEMP_BSEL. When TEMP_BAT is set, a battery measurement is performed as part of each temperature measurement. The value of the battery reading is stored in register BSENSE[7:0]. The battery voltage can be calculated by using the formula in the BATTERY MONITOR section of the electrical characteristics table. In MSN mode, a 100A de-passivation load can be applied to the selected battery (i.e., selected by the TEMP_BSEL bit) by setting the BCURR bit. Battery impedance can be measured by taking a battery measurement with and without BCURR. Regardless of the BCURR bit setting, the battery load is never applied in BRN, LCD, and SLP modes. Digital I/O On reset or power-up, all DIO pins are DIO inputs until they are configured as desired under MPU control. DIO pins can be configured independently as an input or output. The PB pin is a dedicated digital input and is not part of the DIO system. Some pins (DIO2 through DIO11 and PB) can be routed to internal logic such as the interrupt controller or a timer channel. This routing is independent of the direction of the pin, so that outputs can be configured to cause an interrupt or start a timer. A total of 32 combined DIO pins is available for the 71M6545T/HT. These pins can be categorized as follows: 18 DIO pins: * DIO4...DIO5 (2 pins) * DIO9...DIO14 (6 pins) * DIO19...DIO25 (7 pins) * DIO28...DIO29 (2 pins) * DIO55 (1 pin) 9 DIO pins shared with other functions: * DIO0/WPULSE, DIO1/VPULSE (2 pins) www.maximintegrated.com 9 dedicated pins are available: * SPI interface pins: SPI_CSZ, SPI_DO, SPI_DI, SPI_ CKI (4 pins) * ICE Inteface pins: E_RXTX, E_TCLK, E_RST (3 pins) * Test Port pins: TMUX2OUT, TMUXOUT (2 pins) EEPROM Interface The 71M654xT provides hardware support for both twopin (I2C) and three-wire (MICROWIRE) EEPROMs. Two-Pin EEPROM Interface The two-pin serial interface is multiplexed onto the DIO2 (SDCK) and DIO3 (SDATA) pins. Configure the interface for two-pin mode by setting DIO_EEX[1:0] = 01. The MPU communicates with the interface through the SFR registers EEDATA and EECTRL. To write a byte of data to the EEPROM the MPU places the data in EEDATA and then writes the Transmit code to EECTRL. This initiates the transmit operation which is finished when the BUSY bit falls. INT5 is also asserted when BUSY falls. The MPU can then check the RX_ACK bit to see if the EEPROM acknowledged the transmission. A byte is read by writing the Receive command to EECTRL and waiting for the BUSY bit to fall. Upon completion, the received data is in EEDATA. The serial transmit and receive clock is 78kHz during each transmission, and then holds in a high state until the next transmission. The two-pin interface handles protocol details. The MPU can command the interface to issue a start, a repeated start and a stop condition, and it can manage the transmitted ACK status as well. Three-Wire EEPROM Interface The three-wire interface supports standard MICROWIRE (single data pin with clock and select pins) or a subset of SPI (separate DI and DO pins with clock and select pins). MICROWIRE is selected by setting DIO_EEX[1:0] = 10. In this mode, EECTRL selects whether the interface is sending or receiving, and eight bits of data are transferred in each transaction. In this configuration, DIO2 is configured for clock, and DIO3 is configured for data. When separate DI/DO pins are selected (DIO_EEX[1:0] = 11) the interface operates as a subset of SPI. Only SPI modes 0 or 3 are supported. In this configuration, DIO3 is DO and DIO8 is DI. Maxim Integrated 32 71M6545T/71M6545HT Energy Meter ICs UART SPI Flash Mode (SFM) The 71M6545T/HT includes a UART (UART0) that can be programmed to communicate with a variety of AMR modules and other external devices. In normal operation, the SPI slave interface cannot read or write the flash memory. However, the 71M6545T/HT supports an SPI Flash Mode (SFM) which facilitates initial programming of the flash memory. When in SFM mode, the SPI can erase, read, and write the flash memory. Other memory elements such as XRAM and I/O RAM are not accessible in this mode. In order to protect the flash contents, several operations are required before the SFM mode is successfully invoked. SPI Slave Port The SPI slave port communicates directly with the MPU data bus and is able to read and write Data RAM and I/O RAM locations. It is also able to send commands to the MPU. The interface to the slave port consists of the SPI_CSZ, SPI_CKI, SPI_DI and SPI_DO pins. Additionally, the SPI interface allows flash memory to be read and to be programmed. To facilitate flash pro gramming, cycling power or asserting RESET causes the SPI port pins to default to SPI mode. The SPI port is disabled by clearing the SPI_E bit. Possible applications for the SPI interface are: * An external host reads data from CE locations to obtain metering information. This can be used in applications where the 71M654xT function as a smart front-end with preprocessing capability. Since the addresses are in 16-bit format, any type of XRAM data can be accessed: CE, MPU, I/O RAM, but not SFRs or the 80515-internal register bank. * A communication link can be established via the SPI interface: By writing into MPU memory locations, the external host can initiate and control processes in the 71M654xT MPU. Writing to a CE or MPU location normally generates an interrupt, a function that can be used to signal to the MPU that the byte that had just been written by the external host must be read and processed. Data can also be inserted by the external host without generating an interrupt. * An external DSP can access front-end data generated by the ADC. This mode of operation uses the 71M654xT as an analog front-end (AFE). * Flash programming by the external host (SPI Flash Mode). SPI Safe Mode Sometimes it is desirable to prevent the SPI interface from writing to arbitrary RAM locations and thus disturbing MPU and CE operation. This is especially true in AFE applications. For this reason, the SPI SAFE mode was created. In SPI SAFE mode, SPI write operations are disabled except for a 16 byte transfer region at address 0x400 to 0x40F. If the SPI host needs to write to other addresses, it must use the SPI_CMD register to request the write operation from the MPU. SPI SAFE mode is enabled by the SPI_SAFE bit. www.maximintegrated.com In SFM mode, n byte reads and dual-byte writes to flash memory are supported. Since the flash write operation is always based on a two-byte word, the initial address must always be even. Data is written to the 16-bit flash memory bus after the odd word is written. In SFM mode, the MPU is completely halted. The 71M6545T/HT must be reset by the WD timer or by the RESET pin in order to exit SFM mode. If the SPI port is used for code updates (in lieu of a programmer that uses the ICE port), then a code that disables the flash access through SPI can potentially lock out flash program updates. Hardware Watchdog Timer An independent, robust, fixed-duration, watchdog timer (WDT) is included in the 71M6545T/HT. It uses the RTC crystal oscillator as its time base and must be refreshed by the MPU firmware at least every 1.5 seconds. When not refreshed on time, the WDT overflows and the part is reset as if the RESET pin were pulled high, except that the I/O RAM bits are in the same state as after a wake-up from SLP or LCD modes. After 4100 CK32 cycles (or 125 ms) following the WDT overflow, the MPU is launched from program address 0x0000. The watchdog timer is also reset when the internal signal WAKE = 0. Test Ports Two independent multiplexers allow the selection of internal analog and digital signals for the TMUXOUT and TMUX2OUT pins (Table 10). The TMUXOUT and TMUX2OUT pins may be used for diagnostics purposes during the product development cycle or in the production test. The RTC 1-second output may be used to calibrate the crystal oscillator. The RTC 4-second output provides higher precision for RTC calibration. RTCLK may also be used to calibrate the RTC. Maxim Integrated 33 71M6545T/71M6545HT Energy Meter ICs Table 10. Test Ports TMUX[5:0] SIGNAL NAME 1 RTCLK 9 WD_RST Indicates when the MPU has reset the watchdog timer. Can be monitored to determine spare time in the watchdog timer. A CKMPU MPU clock D V3AOK bit Indicates that the V3P3A pin voltage is 3.0 V. The V3P3A and V3P3SYS pins are expected to be tied together at the PCB level. The 71M6543 monitors the V3P3A pin voltage only. E V3OK bit Indicates that the V3P3A pin voltage is 2.8 V. The V3P3A and V3P3SYS pins are expected to be tied together at the PCB level. The 71M654 monitors the V3P3A pin voltage only. 1B MUX_SYNC 1C CE_BUSY interrupt 1D CE_XFER interrupt 1F RTM output from CE DESCRIPTION 32.768 kHz clock waveform Internal multiplexer frame SYNC signal. Note: All TMUX[5:0] values that are not shown are reserved. TMUX2[4:0] SIGNAL NAME 0 WD_OVF 1 PULSE_1S One-second pulse with 25% duty cycle. This signal can be used to measure the deviation of the RTC from an ideal 1-second interval. Multiple cycles should be averaged together to filter out jitter. 2 PULSE_4S Four-second pulse with 25% duty cycle. This signal can be used to measure the deviation of the RTC from an ideal 4-second interval. Multiple cycles should be averaged together to filter out jitter. This pulse provides a more precise measurement than the 1-second pulse. 3 RTCLK 8 9 SPARE[1] bit - I/O RAM 0x2704[1] SPARE[2] bit - I/O RAM 0x2704[2] A WAKE B MUX_SYNC C MCK E GNDD www.maximintegrated.com DESCRIPTION Indicates when the watchdog timer has expired (overflowed). 32.768 kHz clock waveform Copies the value of the bit stored in 0x2704[1]. For general purpose use. Copies the value of the bit stored in 0x2704[2]. For general purpose use. Indicates when a WAKE event has occurred. Internal multiplexer frame SYNC signal. Digital GND. Use this signal to make the TMUX2OUT pin static. Maxim Integrated 34 71M6545T/71M6545HT Energy Meter ICs Table 10. Test Ports (continued) TMUX[5:0] SIGNAL NAME 1 RTCLK 12 INT0 - DIG I/O DESCRIPTION 32.768 kHz clock waveform 13 INT1 - DIG I/O 14 INT2 - CE_PULSE 15 INT3 - CE_BUSY 16 INT4 - VSTAT 17 INT5 - EEPROM/SPI 18 INT6 - XFER, RTC 1F RTM_CK (flash) Interrupts Note: All TMUX2[4:0] values which are not shown are reserved. Functional Description Theory of Operation The energy delivered by a power source into a load can be expressed as: t E = V(t)I(t)dt 0 Assuming phase angles are constant, the following formulae apply: * P = Real Energy [Wh] = V x A x cos () x t * Q = Reactive Energy [VARh] = V x A x sin () x t * S = Apparent Energy [VAh] = P2 + Q2 For a practical meter, not only voltage and current amplitudes, but also phase angles and harmonic content may change constantly. Thus, simple RMS measurements are inherently inaccurate. The 71M654xT, however, functions by emulating the integral operation above by processing current and voltage samples at a constant rate. As long as the ADC resolution is high enough and the sample frequency is beyond the harmonic range of interest, the current and voltage samples, multiplied by the sample period yield an accurate value for the instantaneous energy. Summing the instantaneous energy quantities over time provides accurate results for accumulated energy. The application of 240V AC and 100A results in an accumulation of 480Ws (= 0.133 Wh) over the 20ms period, as indicated by the accumulated power curve. The described sampling method works reliably, even in the presence of dynamic phase shift and harmonic distortion. Battery Modes The 71M654xT can operate in one of three power modes: mission (MSN), brownout (BRN), or sleep (SLP). www.maximintegrated.com Shortly after system power (VV3P3SYS) is applied, the part is in mission mode. MSN mode means that the part is operating with system power and that the internal PLL is stable. This mode is the normal operating mode where the part is capable of measuring energy. When system power is not available, the 71M654xT is in one of three battery modes: BRN or SLP. An internal comparator monitors the voltage at the VV3P3A pin (note that VV3P3SYS and VV3P3A are typically connected together at the PCB level). When the VV3P3A DC voltage drops below 2.8 VDC, the comparator resets an internal power status bit called V3OK. As soon as system power is removed and V3OK = 0, the 71M654xT switches to battery power (VBAT pin), notifies the MPU by issuing an interrupt and updates the VSTAT[2:0] register. The MPU continues to execute code when the system transitions from MSN to BRN mode. Depending on the MPU code, the MPU can choose to stay in BRN mode, or transition to SLP mode. BRN mode is similar to MSN mode except that resources powered by VV3P3A power, such as the ADC are inaccurate. In BRN mode the CE continues to run and should be turned off to conserve VBAT power. Also, the PLL continues to function at the same frequency as in MSN mode and its frequency should be reduced to save power. When system power is restored, the 71M654xT automatically transitions from any of the battery modes (BRN, LCD, SLP) back to MSN mode, switches back to using system power (VV3P3SYS, VV3P3A), issues an interrupt and updates VSTAT[1:0]. The MPU software should restore MSN mode operation by issuing a soft reset to restore system settings to values appropriate for MSN mode. Maxim Integrated 35 71M6545T/71M6545HT Energy Meter ICs Transitions from SLP mode to BRN mode can be initiated by the following events: 1) Wake-up timer timeout. 2) Pushbutton (PB) is activated. 3) A rising edge on DIO4 or DIO55. 4) Activity on the RX or OPT_RX pins. Brownout Mode In BRN mode, most nonmetering digital functions are active including ICE, UART, EEPROM, and RTC. In BRN mode, the PLL continues to function at the same frequency as MSN mode. It is up to the MPU to reduce the PLL frequency or the MPU frequency in order to minimize power consumption. From BRN mode, the MPU can choose to enter SLP mode. When system power is restored while the 71M654xT is in BRN mode, the part automatically transitions to MSN mode. Sleep Mode When the VV3P3SYS pin voltage drops below 2.8 VDC, the 71M654xT enters BRN mode and the VV3P3D pin obtains power from the VBAT pin instead of the VV3P3SYS pin. Once in BRN mode, the MPU may invoke SLP mode by setting the SLEEP bit. The purpose of SLP mode is to consume the least amount power while still maintaining the real time clock, temperature compensation of the RTC, and the nonvolatile portions of the I/O RAM. In SLP mode, the VV3P3D pin is disconnected, removing all sources of current leakage from the VBAT pin. The nonvolatile I/O RAM locations and the SLP mode functions, such as the temperature sensor, oscillator, RTC, and the RTC temperature compensation are powered by the VBAT_RTC pin. SLP mode can be exited only by a system power-up event or one of the wake methods. If the SLEEP bit is asserted when VV3P3SYS pin power is present (i.e., while in MSN mode), the 71M654xT enters SLP mode, resetting the internal WAKE signal, at which point the 71M654xT begins the standard wake from sleep procedures. When power is restored to the VV3P3SYS pin, the 71M654xT transitions from SLP mode to MSN mode and the MPU PC (Program Counter) is initialized to 0x0000. At this point, the XRAM is in an undefined state, but nonvolatile I/O RAM locations are preserved. Applications Information Connecting 5V Devices All digital input pins of the 71M654xT are compatible with external 5V devices. I/O pins configured as inputs do not require current-limiting resistors when they are connected to external 5V devices. Direct Connection of Sensors The 71M654xT supports direct connection of current transformer and shunt-fed sensors. Using the 71M6545T/HT with Local Sensors The 71M6545T/HT can be configured to operate with locally connected current sensors. All current inputs are connected to a current transformer (CT) and are therefore isolated. This configuration implements a polyphase 500 400 300 V(V), I(A), P(Ws) 200 100 0 -100 -200 VOLTAGE (V) -300 CURRENT (A) -400 ENERGY PER INTERVAL (Ws) -500 ACCUMULATED ENERGY (Ws) 0 5 10 15 20 TIME (ms) Figure 6. Waveforms Comparing Voltage, Current, Energy per Interval, and Accumulated Energy www.maximintegrated.com Maxim Integrated 36 71M6545T/71M6545HT Energy Meter ICs measurement with tamper-detection using one current sensor to measure the neutral current. For best performance, all current sensor inputs are configured for differential mode. Connecting Three-Wire EEPROMs Using the 71M6545T/HT with Remote Sensors UART The 71M6545T/HT can be configured to operate with 71M6x03 remote sensor interfaces and current shunts. This configuration implements a polyphase measurement with tamper-detection. For best performance, the IADC0-IADC1 current sensor input is configured for differential mode (DIFFA_E = 1). The outputs of the 71M6x03 isolated sensor interface are routed through a pulse transformer, which is connected to the current input pins (IADC2-IADC7). The current input pins (IADC2-IADC7) must be configured for remote sensor communication (i.e., RMT_E =1). Metrology Temperature Compensation Since the VREF bandgap amplifier is chopper-stabilized the DC offset voltage (the most significant long-term drift mechanism in bandgap voltage references) is automatically removed by the chopper circuit. Both the 71M654xT and the 71M6x03 feature chopper circuits for their respective VREF voltage reference. VREF is trimmed to a target value of 1.195V during the device manufacturing process and the result of the trim stored in nonvolatile fuses. For the 71M654xT device (Q0.5% energy accuracy), the TRIMT[7:0] value can be read by the MPU during initialization in order to calculate parabolic temperature compensation coefficients suitable for each individual 71M654xT device. The resulting temperature coefficient for VREF in the 71M654xT is 40 ppm/C. By using the trim information in the TRIMT register and the sensed temperature, a gain adjustment for the sensor can be computed. See the 71M6545T/HT User's Guide for more information about compensating sensors for temperature variations. Connecting I2C EEPROMs I2C EEPROMs or other I2C compatible devices should be connected to the DIO pins DIO2 and DIO3. Pullup resistors of roughly 10k to VV3P3D (to ensure operation in BRN mode) should be used for both SDCK and SDATA signals. The DIO_EEX[1:0] field in I/O RAM must be set to 01 in order to convert the DIO pins DIO2 and DIO3 to I2C pins SDCK and SDATA. www.maximintegrated.com MICROWIRE EEPROMs and other compatible devices should be connected to the DIO pins DIO2/SDCK and DIO3/SDATA. The UART0 RX pin should be pulled down by a 10k resistor and additionally protected by a 100pF ceramic capacitor. With modulation, an optical emitter can be operated at higher current than nominal, enabling it to increase the distance along the optical path. If operation in BRN mode is desired, the external components should be connected to VV3P3D. However, it is recommended to limit the current to a few mA. Reset Even though a functional meter does not necessarily need a reset switch, it is useful to have a reset push button for prototyping. The RESET signal may be sourced from VV3P3SYS (functional in MSN mode only), VV3P3D (MSN and BRN modes), or VBAT (all modes, if a battery is present), or from a combination of these sources, depending on the application. RESET causes the CPU to restart and returns all IO RAM values to their default values. For a production meter, the RESET pin should be protected by the external components. R1 should be in the range of 100 and mounted as closely as possible to the IC. Emulator Port Pins Even when the emulator is not used, small shunt capacitors to ground (22pF) should be used for protection from EMI. Production boards should have the ICE_E pin connected to ground. MPU Firmware Library All application-specific MPU functions are featured in the demonstration C source code supplied by Maxim Integrated. The code is available as part of the Demonstration Kit for the 71M6545T/HT. The Demonstration Kits come with pre programmed with demo firmware and mounted on a functional sample meter Demo Board. The Demo Boards allow for quick and efficient evaluation of the IC without having to write firmware or having to supply an in-circuit emulator (ICE). Contact Maxim Integrated for information on price and availability of demonstration boards. Maxim Integrated 37 71M6545T/71M6545HT Energy Meter ICs RIN VA VIN ROUT V3P3A Figure 7. Typical Voltage Sense Circuit Using Resistive Divider IIN IOUT IAP VOUT RBURDEN CT V3P3A NOISE FILTER 1:N Figure 8. Typical Current-Sense Circuit Using Current Transformer in a Single-Ended Configuration IOUT IAP IIN CT RBURDEN V3P3A VOUT 1:N IAN BIAS NETWORK AND NOISE FILTER Figure 9. Typical Current-Sense Circuit Using Current Transformer in a Differential Configuration IIN RSHUNT IAP VOUT V3P3A IAN BIAS NETWORK AND NOISE FILTER Figure 10. Typical Current-Sense Circuit Using Shunt in a Differential Configuration www.maximintegrated.com Maxim Integrated 38 71M6545T/71M6545HT Energy Meter ICs CURRENT TRANSFORMERS PHASE A LOAD NEUTRAL PHASE B PHASE C NOTE: THIS SYSTEM IS REFERENCED TO NEUTRAL POWER SUPPLY NEUTRAL MUX AND ADC VV3P3A V V3P3SYS RESISTOR DIVIDERS IADC0 IA IADC1 VADC8 (VA) IADC2 IB IADC3 VADC9 (VB) IADC4 IC IADC5 VADC10 (VC) IADC6 IN* IADC7 71M6545T 71M6545HT REGULATOR TEMPERATURE SENSOR BATTERY MONITOR RAM OSCILLATOR/PLL RTC BATTERY XIN 32kHz TX XOUT RX MPU RTC TIMERS FLASH MEMORY SPI INTERFACE DIO, PULSES, LEDs DIO 24 TMUX COMPUTE ENGINE WPULSE XPULSE RPULSE YPULSE PULSES XFER_BUSY DIO I2C OR WIRE EEPROM VV3P3D ICE HOST PB VBAT_RTC SERIAL PORTS SPI_CKI SPI_DI SPI_DO SPI_CSZ GNDD PWR MODE CONTROL VREF AMR GNDA 3.3VDC SAG *IN = OPTIONAL NEUTRAL CURRENT Figure 11. 71M6545T/HT Typical Operating Circuit Using Locally Connected Sensors www.maximintegrated.com Maxim Integrated 39 71M6545T/71M6545HT Energy Meter ICs SHUNT CURRENT SENSORS C LOAD NEUTRAL B A POWER SUPPLY 71M6xx3 71M6xx3 NEUTRAL PULSE TRANSFORMERS 71M6xx3 NOTE: THIS SYSTEM IS REFERENCED TO NEUTRAL MUX AND ADC RESISTOR DIVIDERS IADC0 IN* IADC1 VADC10 (VC) IADC6 IC IADC7 VADC9 (VB) IADC4 IB IADC5 VADC8 (VA) IADC2 IA IADC3 VV3P3A VV3P3SYS 71M6545T 71M6545HT REGULATOR TEMPERATURE SENSOR BATTERY MONITOR RAM OSCILLATOR/PLL RTC BATTERY XIN 32kHz TX XOUT RX MPU RTC TIMERS FLASH MEMORY SPI INTERFACE DIO, PULSES, LEDs DIO 24 DIO I2C OR WIRE EEPROM VV3P3D ICE HOST PB VBAT_RTC SERIAL PORTS SPI_CKI SPI_DI SPI_DO SPI_CSZ GNDD PWR MODE CONTROL VREF AMR GNDA TMUX COMPUTE ENGINE WPULSE XPULSE RPULSE YPULSE PULSES XFER_BUSY 3.3VDC SAG *IN = OPTIONAL NEUTRAL CURRENT Figure 12. 71M6545T/HT Typical Operating Circuit Using Remote Neutral Current Sensor www.maximintegrated.com Maxim Integrated 40 71M6545T/71M6545HT Energy Meter ICs V3P3D V3P3D 10k 71M654xT 10k ICE_E 62 EEPROM SEGDIO2/SDCK SDCK SEGDIO3/SDATA SDATA E_RST 62 E_RXT 62 22pF Figure 13. Typical I2C Operating Circuit E_TCLK 22pF 22pF 71M654xT Figure 16. Typical Emulator Connections RX RX 71M654xT 100pF 10k TX TX Figure 14. Typical UART Operating Circuit VBAT/ V3P3D R2 1k V3P3D RESET SWITCH 71M654xT RESET 0.1F R1 10k GNDD RESET R1 100 GNDD Figure 15. Typical Reset Circuits www.maximintegrated.com Maxim Integrated 41 71M6545T/71M6545HT Meter Calibration Once the 71M654xT energy meter device has been installed in a meter system, it must be calibrated. A complete calibration includes: Energy Meter ICs Unimplemented bits have no memory storage, writing them has no effect, and reading them always returns zero. * Establishment of the reference temperature (typically 22C). Reserved bits are identified with an `R', and must always be written with a zero. Writing values other than zero to reserved bits may have undesirable side effects and must be avoided. * Calibration of the metrology section: calibration for tolerances of the current sensors, voltage dividers and signal conditioning components as well as of the internal reference voltage (VREF) at the reference temperature. Nonvolatile bits are shaded in dark gray. Nonvolatile bits are backed up during power failures if the system includes a battery connected to the VBAT pin. The metrology section can be calibrated using the gain and phase adjustment factors accessible to the CE. The gain adjustment is used to compensate for tolerances of components used for signal conditioning, especially the resistive components. Phase adjustment is provided to compensate for phase shifts introduced by the current sensors or by the effects of reactive power supplies. I/O RAM Map: Details Writable bits are written by the MPU into configuration RAM. Typically, they are initially stored in flash memory and copied to the configuration RAM by the MPU. Some of the more frequently programmed bits are mapped to the MPU SFR memory space. The remaining bits are mapped to the address space 0x2XXX. The RST and WK columns describe the bit values upon reset and wake, respectively. No entry in one of these columns means the bit is either read-only or is powered by the NV supply and is not initialized. Write-only bits return zero when they are read. Due to the flexibility of the MPU firmware, any calibration method, such as calibration based on energy, or current and voltage can be implemented. It is also possible to implement segment-wise calibration (depending on current range). The 71M6545T/HT support common industry standard calibration techniques, such as single-point (energy-only), multipoint (energy, VRMS, IRMS), and auto-calibration. Contact Maxim Integrated to obtain a copy of the latest calibration spreadsheet file for the 71M654xT. Firmware Interface Overview: Functional Order The I/O RAM locations at addresses 0x2000 to 0x20FF have sequential addresses to facilitate reading by the MPU. These I/O RAM locations are usually modified only at power-up. These addresses are an alternative sequential address to subsequent addresses (above 0x2100). For instance, EQU[2:0] can be accessed at I/O RAM 0x2000[7:5] or at I/O RAM 0x2106[7:5]. Unimplemented (U) and reserved (R) bits are shaded in light gray. Unimplemented bits are identified with a `U'. www.maximintegrated.com Locations that are shaded in grey are nonvolatile (i.e., battery-backed). Reading the Info Page Information useful for calibrating the temperature sensor and other functions is available in trim fuses. The trim fuse values provided in the 71M654xT devices cannot be directly accessed through the I/O RAM space. They reside in a special area termed the Info Page. The MPU gains access to the Info Page by setting the INFO_PG (I/O RAM 0x270B[0]) control bit. Once this bit is set, Info Page contents are accessible in program memory space starting at the address specified by the contents of CE_ LCTN[6:0] (71M654xGT) or CE_LCTN[5:0] (71M654xFT) (I/O RAM 0x2109[6:0] for 71M654xGT or 0x2109[5:0] for 71M654xFT). These pointers specify a base address at a 1KB address boundary which is at 1024 x CE_LCTN[6:0] (71M654xGT) or CE_LCTN[5:0] (71M654xFT). Table 11 provides a list of the available trim fuses and their corre- Maxim Integrated 42 71M6545T/71M6545HT Energy Meter ICs Table 11. Info Page Trim Fuses REGISTER NAME DEFINITION LOCATION ADDRESS FORMAT TYPICAL VALUE STEMP_T85_P STEMP at +85C Info Block 0xAA, 0xAB 16 bits, signed 4400 STEMP_T22_P STEMP at +22C Info Block 0x8A, 0x8B 13 bits, unsigned 3600 T85_P Probe temperature at +85C Info Block 0xA6, 0xA7 16 bits signed 605 T22_P Probe temperature at +22C Info Block 0x9A 8 bits signed 35 I/O RAM 0x2882, 0x2882 STEMP Temperature sensor sponding offsets relative to the Info Page base address. After reading the desired Info Page information, the MPU must reset the INFO_PG bit. The code below provides an example for reading Info Page fuse trims. In this code example, the address, px is a pointer to the MPU's code space. In assembly language, the Info Page data objects, which are read-only, must be accessed with the MOVC 8051 instruction. In the C-language, Info Page trim fuses must be fetched with a pointer of the correct width, depending on the format of the trim fuse (an 8-bit or a 16-bit data object). The case statements in the code example below perform casts to obtain a pointer of the correct size for each object, as needed. In assembly language, the MPU has to form 11-bit or 16-bit values from two separate 8-bit fetches, depending on the object being fetched. The byte values containing less than 8 valid bits are LSB justified. For example Info Page offset 0x90 is an 8-bit object whose three LSBs are bits [10:8] of the complete TEMP_85[10:0] 11-bit object. The Info Page data objects are 2s complement format and should be sign-extended when read into a 16-bit data type (see case _TEMP85 in the code example). www.maximintegrated.com 11 bits, sign extended #if HIGH_PRECISION_METER int16_t read_trim (enum eTRIMSEL select) { uint8r_t *px; int16_t x; px = ((uint16_t)select) + ((uint8r_t *)(CE3 << 10)); switch (select) { default: case _TRIMBGD: INFO_PG = 1; x = *px; INFO_PG = 0; break; case _TRIMBGB: INFO_PG = 1; x = *(uint16r_t*)px; INFO_PG = 0; break; case _TEMP85: INFO_PG = 1; x = *(uint16r_t*)px; INFO_PG = 0; if (x & 0x800) x |= 0xF800; break; } return (x); } #endif //#if HIGH_PRECISION_METER Maxim Integrated 43 71M6545T/71M6545HT Energy Meter ICs Table 12. I/O RAM Locations in Numerical Order NAME ADDR CE6 2000 BIT 7 BIT 6 BIT 5 BIT 4 CE5 2001 CE4 2002 CE3 2003 CE2 2004 CE1 2005 CE0 2006 RCE0 2007 RTMUX 2008 U Reserved 2009 U MUX5 200A MUX_DIV[3:0] MUX10_SEL MUX4 200B MUX9_SEL MUX8_SEL MUX3 200C MUX7_SEL MUX6_SEL MUX2 200D MUX5_SEL MUX4_SEL MUX1 200E MUX3_SEL MUX2_SEL MUX0 200F TEMP 2010 TEMP_BSEL TEMP_PWR OSC_COMP TEMP_BAT U TEMP_PER[2:0] DIO_R5 201B U U U U U DIO_RPB[2:0] DIO_R4 201C U U DIO_R10[2:0] DIO_R3 201D U DIO_R9[2:0] U DIO_R8[2:0] DIO_R2 201E U DIO_R7[2:0] U DIO_R6[2:0] DIO_R1 201F U DIO_R5[2:0] U DIO_R4[2:0] DIO_R0 2020 U DIO_R3[2:0] U DIO_R2[2:0] DIO0 2021 DIO1 2022 DIO_PW DIO_PV DIO2 2023 DIO_PX DIO_PY U INT1_E 2024 EX_EEX EX_XPULSE EX_YPULSE INT2_E 2025 EX_SPI EX_WPULSE EX_VPULSE WAKE_E 2026 U EW_TEMP U SFMM 2080 SFMM[7:0] (via SPI slave port only) SFMS 2081 SFMS[7:0] (via SPI slave port only) EQU[2:0] U BIT 3 U U BIT 2 CHOP_E[1:0] U BIT 1 BIT 0 RTM_E CE_E SUM_SAMPS[12:8] SUM_SAMPS[7:0] U U CE_LCTN[5:0] PLS_MAXWIDTH[7:0] PLS_INTERVAL[7:0] DIFF6_E DIFF4_E CHOPR[1:0] DIFF2_E DIFF0_E RFLY_DIS RMT6_E RMT4_E RMT2_E TMUXRB[2:0] U FIR_LEN[1:0] R U R TMUXRA[2:0] U U MUX1_SEL U U MUX0_SEL DIO_R11[2:0] DIO_EEX[1:0] R U R PLS_INV U U OPT_TXMOD OPT_TXINV U OPT_RXDIS OPT_RXINV OPT_BB U U U U U EX_RTCT EX_TCTEMP EX_RTC1M EX_RTC1S EX_XFER EW_RX EW_PB EW_DIO4 U EW_DIO55 OPT_FDC[1:0] OPT_TXE[1:0] CE AND ADC MUX5 2100 MUX_DIV[3:0] MUX10_SEL[3:0] MUX4 2101 MUX9_SEL[3:0] MUX8_SEL[3:0] MUX3 2102 MUX7_SEL[3:0] MUX6_SEL[3:0] MUX2 2103 MUX5_SEL[3:0] MUX4_SEL[3:0] MUX1 2104 MUX3_SEL[3:0] MUX2_SEL[3:0] MUX0 2105 MUX1_SEL[3:0] CE6 2106 CE5 2107 CE4 2108 CE3 2109 CE2 210A MUX0_SEL[3:0] EQU[2:0] U U U U U U CHOP_E[1:0] RTM_E CE_E SUM_SAMPS[12:8] SUM_SAMPS[7:0] www.maximintegrated.com CE_LCTN[5:0] PLS_MAXWIDTH[7:0] Maxim Integrated 44 71M6545T/71M6545HT Energy Meter ICs Table 12. I/O RAM Locations in Numerical Order (continued) NAME ADDR CE1 210B BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 CE0 210C R R DIFFB_E DIFFA_E RFLY_DIS FIR_LEN[1:0] PLS_INV CE0 RTM0 210D U U U U RTM0 210E RTM0[7:0] U U RTM1 210F RTM1[7:0] RTM2 2110 RTM2[7:0] RTM3 2111 FIR_EXT 2112 PLS_INTERVAL[7:0] RTM0[9:8] RTM3[7:0] U U U U SLOT_EXT[3:0] ADC_DIV PLL_FAST CLOCK GENERATION CKGN 2200 OUT_SQ[1:0] RESET MPU_DIV[2:0] VREF TRIM FUSES TRIMT 2309 TRIMT[7:0] DIO DIO_R5 2450 U U DIO_RPB[2:0] DIO_R4 2451 U U DIO_R11[2:0] U DIO_R10[2:0] DIO_R3 2452 U DIO_R9[2:0] U DIO_R8[2:0] DIO_R2 2453 U DIO_R7[2:0] U DIO_R6[2:0] DIO_R1 2454 U DIO_R5[2:0] U DIO_R4[2:0] DIO_R0 2455 U DIO_R3[2:0] U DIO_R2[2:0] DIO0 2456 DIO1 2457 DIO_PW DIO_PV DIO2 2458 DIO_PX DIO_PY DIO_EEX[1:0] U U U UMUX_SEL OPT_TXE[1:0] OPT_FDC[1:0] U OUT_SQE OPT_TXMOD OPT_TXINV U OPT_RXDIS OPT_RXINV OPT_TXINV U U U U NONVOLATILE BITS TMUX 2502 U U TMUX2 2503 U U U TMUX[5:0] TC_A1 2508 U U U TC_A2 2509 TC_B1 250A TC_B2 250B PQMASK 2511 U U U U TSEL 2518 U U U TEMP_SELE TSBASE1 2519 U U U U TSBASE2 251A TSMAX 251B U TSMIN 251C U TSFILT 251D U TMUX2[4:0] U U U TC_A[9:8] TC_A[7:0] U U U U TC_B[11:8] TC_B[7:0] U PQMASK[2:0] TEMP_SEL[3:0] U SBASE[10:8] SBASE[7:0] SMAX[6:0] SMIN[6:0] U U U SFILT[3:0] 71M6x03 REMOTE INTERFACE REMOTE2 2602 RMT_RD[15:8] REMOTE1 2603 RMT_RD[7:0] www.maximintegrated.com Maxim Integrated 45 71M6545T/71M6545HT Energy Meter ICs Table 12. I/O RAM Locations in Numerical Order (continued) NAME ADDR BIT 7 BIT 6 2700 EX_EEX EX_XPULSE EX_SPI EX_WPULSE BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 EX_YPULSE EX_RTCT EX_TCTEMP EX_RTC1M EX_RTC1S EX_XFER EX_VPULSE U U U U U R FLSH_RDE FLSH_WRE R RBITS INT1_E INT2_E 2701 SECURE 2702 Analog0 2704 VREF_CAL VREF_DIS PRE_E ADC_E BCURR INTBITS 2707 U INT6 INT5 INT4 INT3 INT2 INT1 FLAG0 SFR E8 IE_EEX IE_XPULSE IE_YPULSE IE_RTCT IE_TCTEMP IE_RTC1M IE_RTC1S IE_XFER FLAG1 SFR F8 IE_SPI IE_WPULSE IE_VPULSE U U U U PB_STATE STAT SFR F9 U U U PLL_OK U REMOTE0 SFR FC U PERR_RD PERR_WR SPI1 SFR FD FLSH_UNLOCK[3:0] SPARE[2:0] INT0 VSTAT[2:0] RCMD[4:0] SPI_CMD[7:0] SPI0 2708 RCE0 2709 SPI_STAT[7:0] RTMUX 270A U INFO_PG 270B CHOPR[1:0] R R RMT_E R R R U U U U U U U U INFO_PG U PORT_E SPI_E SPI_SAFE U U U U U DIO3 270C U TNM1 2710 U TNM2 2711 TM1 2712 R R R TMUXRA[2:0] TEMP_NMAX[14:8] TEMP_NMAX[7:0] U U U U TEMP_M[11:8] TM2 2713 TEMP_M[7:0] TNB1 2714 TEMP_NBAT[15:8] TNB2 2715 TEMP_NBAT[7:0] NV RAM AND RTC NVRAMxx 2800 NVRAM[0] to NVRAM[7F] - 128 bytes, direct access, 0x2800 to 0x287F WAKE 2880 WAKE_TMR[7:0] STEMP1 2881 STEMP[15:8] STEMP0 2882 STEMP[7:0] BSENSE 2885 PQ2 2886 PQ1 2887 PQ0 2888 RTC0 2890 BSENSE[7:0] U U U PQ[20:16] PQ[15:8] PQ[7:0] RTC_WR RTC_RD U RTC2 2892 RTC3 2893 U U RTC4 2894 U U RTC5 2895 U U U RTC6 2896 U U U RTC7 2897 U U U RTC8 2898 U U U RTC9 2899 RTC11 289C RTC12 289D RTC_FAIL U U RTC_SBSC[7:0] RTC_SEC[5:0] RTC_MIN[5:0] RTC_HR[4:0] U U RTC_DAY[2:0] RTC_DATE[4:0] U RTC_MO[3:0] RTC_YR[7:0] U www.maximintegrated.com U U U TC_C[11:8] TC_C[7:0] Maxim Integrated 46 71M6545T/71M6545HT Energy Meter ICs Table 12. I/O RAM Locations in Numerical Order (continued) NAME ADDR BIT 7 RTC13 289E U BIT 6 U BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 RTC14 289F U U U TEMP 28A0 TEMP_BSEL TEMP_PWR OSC_COMP TEMP_BAT TBYTE_BUSY WF1 28B0 WF_CSTART WF_RST WF_RSTBIT WF_OVF WF_ERST WF_BADVDD U U WF2 28B1 U WF_TEMP WF_TMR WF_RX WF_PB WF_DIO4 U WF_DIO55 MISC 28B2 SLEEP U WAKE_ARM U U U U U WAKE_E 28B3 U EW_TEMP U EW_RX EW_PB EW_DIO4 U EW_DIO55 WDRST 28B4 WD_RST TEMP_START U U U U U U FLSH_MEEN FLSH_PWE RTC_TMIN[5:0] RTC_THR[4:0] TEMP_PER[2:0] MPU PORTS P3 SFR B0 DIO_DIR[15:12] DIO[15:12] P2 SFR A0 DIO_DIR[11:8] DIO[11:8] P1 SFR 90 DIO_DIR[7:4] DIO[7:4] P0 SFR 80 DIO_DIR[3:0] DIO[3:0] FLASH FLSH_ERASE SFR 94 FLSH_CTL SFR B2 FLSH_ PGADR FLSH_ERASE[7:0] PREBOOT SECURE SFR B7 U U FLSH_PEND FLSH_PSTWR FLSH_PGADR[6:0] U I2C EEDATA SFR 9E EEDATA[7:0] EECTRL SFR 9F EECTRL[7:0] Table 13. I/O RAM Locations in Alphabetical Order NAME ADC_E LOCATION RST WK DIR 2704[4] 0 0 DESCRIPTION R/W Enables ADC and VREF. When disabled, reduces bias current. ADC_DIV controls the rate of the ADC and FIR clocks. The ADC_DIV setting determines whether MCK is divided by 4 or 8: 0 = MCK/4 1 = MCK/8 The resulting ADC and FIR clock is as shown below. ADC_DIV BCURR 2200[5] 0 0 R/W PLL_FAST = 0 PLL_FAST = 1 MCK 6.291456MHz 19.660800MHz ADC_DIV = 0 1.572864MHz 4.9152MHz ADC_DIV = 1 0.786432MHz 2.4576MHz 2704[3] 0 0 2885[7:0] - - 2106[0] 0 0 CE_LCTN[5:0] 2109[5:0] 31 31 R/W CE program location. The starting address for the CE program is 1024 x CE_LCTN. CHIP_ID[15:0] 2300[7:0] 2301[7:0] 0 0 0 0 BSENSE[7:0] CE_E www.maximintegrated.com R/W Connects a 100A load to the battery selected by TEMP_BSEL. R The result of the battery measurement. R/W CE enable. R R These bytes contain the chip identification. CHIP_ID[15:0]: 71M6545T (11B4h) 71M6545HT (11BCh) Maxim Integrated 47 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME CHOP_E[1:0] LOCATION RST WK DIR Chop enable for the reference bandgap circuit. The value of CHOP changes on the rising edge of MUXSYNC according to the value in CHOP_E: R/W 00 = toggle1 01 = positive 10 = reversed 11 = toggle 1except at the mux sync edge at the end of an accumulation interval. Note: CHOP_E is the preferred mode for low-noise applications. 0 0 2709[7:6] 00 The CHOP settings for the remote sensor. 00 = Auto chop. Change every MUX frame. 00 R/W 01 = Positive 10 = Negative 11 = Auto chop. Same as 00. DIFF0_E 210C[4] 0 0 R/W Enables IADC0-IADC1 differential configuration. DIFF2_E 210C[5] 0 0 R/W Enables IADC2-IADC3 differential configuration. DIFF4_E 210C[6] 0 0 R/W Enables IADC4-IADC5 differential configuration. DIFF6_E 210C[7] 0 0 R/W Enables IADC6-IADC7 differential configuration. 2455[2:0] 2455[6:4] 2454[2:0] 2454[6:4] 2453[2:0] 2453[6:4] 2452[2:0] 2452[6:4] 2451[2:0] 2451[6:4] 2450[2:0] 0 0 0 0 0 0 0 0 0 0 0 CHOPR[1:0] DIO_R2[2:0] DIO_R3[2:0] DIO_R4[2:0] DIO_R5[2:0] DIO_R6[2:0] DIO_R7[2:0] DIO_R8[2:0] DIO_R9[2:0] DIO_R10[2:0] DIO_R11[2:0] DIO_RPB[2:0] 2106[3:2] DESCRIPTION Connects PB and dedicated I/O pins DIO2 through DIO11 to internal resources. If more than one input is connected to the same resource, the MULTIPLE column below specifies how they are combined. DIO_Rx - R/W RESOURCE MULTIPLE 0 NONE - 1 Reserved OR 2 T0 (Timer0 clock or gate) OR 3 T1 (Timer1 clock or gate) OR 4 IO interrupt (int0) OR 5 IO interrupt (int1) OR DIO_DIR[15:12] DIO_DIR[11:8] DIO_DIR[7:4] DIO_DIR[3:0] SFR B0[7:4] SFR A0[7:4] SFR 90[7:4] SFR 80[7:4] F F Programs the direction of the first 16 DIO pins. 1 indicates output. Ignored if the pin is not configured as I/O. See R/W DIO_PV and DIO_PW for special option for the DIO0 and DIO1 outputs. See DIO_EEX for special option for DIO2 and DIO3. Note that the direction of DIO pins above 15 is set by DIOx[1]. See PORT_E to avoid power-up spikes. DIO[15:12] DIO[11:8] DIO[7:4] DIO[3:0] SFR B0[3:0] SFR A0[3:0] SFR 90[3:0] SFR 80[3:0] F F R/W The value on the first 16 DIO pins. When written, changes data on pins configured as outputs. Note that the data for DIO pins above 15 is set by DIOx[0]. When set, converts pins DIO3/DIO2 to interface with external EEPROM. DIO2 becomes SDCK and DIO3 becomes bidirectional SDATA. DIO_EEX[1:0] DIO_EEX[1:0] 2456[7:6] 0 - R/W 00 FUNCTION Disable EEPROM interface 01 2-Wire EEPROM interface 10 3-Wire EEPROM interface 11 3-Wire EEPROM interface with separate DO (DIO3) and DI (DIO8) pins. DIO_PV 2457[6] 0 - R/W Causes VARPULSE to be output on pin DIO1. DIO_PW 2457[7] 0 - R/W Causes WPULSE to be output on pin DIO0. DIO_PX 2458[7] 0 - R/W Causes XPULSE to be output on pin DIO6. DIO_PY 2458[6] 0 - R/W Causes YPULSE to be output on pin DIO7. EEDATA[7:0] SFR 9E 0 0 R/W Serial EEPROM interface data. www.maximintegrated.com Maxim Integrated 48 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME LOCATION RST WK DIR DESCRIPTION Serial EEPROM interface control. EECTRL[7:0] SFR 9F 0 0 R/W STATUS BIT NAME READ/ WRITE RESET STATE POLARITY DESCRIPTION 7 ERROR R 0 Positive 1 when an illegal command is received. 6 BUSY R 0 Positive 1 when serial data bus is busy. 5 RX_ACK R 1 Positive 1 indicates that the EEPROM sent an ACK bit. Specifies the power equation. EQU[2:0] 2106[7:5] 0 0 R/W EQU[2:0] DESCRIPTION ELEMENT 0 ELEMENT 1 ELEMENT 2 RECOMMENDED MUX SEQUENCE 3 2 element 4W 3f Delta VA(IA-IB)/2 0 VC x IC IA VA IB VB IC VC 4 2 element 4W 3f Wye VA(IA-IB)/2 VB(IC-IB)/2 0 IA VA IB VB IC VC 5 2 element 4W 3f Wye VA x IA VB x IB VC x IC IA VA IB VB IC VC Note: The available CE codes implement only equation 5. Contact your Maxim representative to obtain CE codes for equation 3 or 4. EX_XFER EX_RTC1S EX_RTC1M EX_TCTEMP EX_RTCT EX_SPI EX_EEX EX_XPULSE EX_YPULSE EX_WPULSE EX_VPULSE 2700[0] 2700[1] 2700[2] 2700[3] 2700[4] 2701[7] 2700[7] 2700[6] 2700[5] 2701[6] 2701[5] 0 0 Interrupt enable bits. These bits enable the XFER_BUSY, the RTC_1SEC, etc. The bits are set by hardware and R/W cannot be set by writing a 1. The bits are reset by writing 0. Note that if one of these interrupts is to enabled, its corresponding 8051 EX enable bit must also be set. EW_DIO4 28B3[2] 0 - R/W Connects DIO4 to the WAKE logic and permits DIO4 rising to wake the part. This bit has no effect unless DIO4 is configured as a digital input. EW_DIO55 28B3[0] 0 - R/W Connects DIO55 to the WAKE logic and permits DIO55 rising to wake the part. This bit has no effect unless DIO55 is configured as a digital input. EW_PB 28B3[3] 0 - R/W Connects PB to the WAKE logic and permits PB rising to wake the part. PB is always configured as an input. EW_RX 28B3[4] 0 - R/W Connects RX to the WAKE logic and permits RX rising to wake the part. See the WAKE description on page 84 for de-bounce issues. EW_TEMP 28B3[5] 0 - R/W Connects the temperature range check hardware to the WAKE logic and permits the range check hardware to wake the part. www.maximintegrated.com Maxim Integrated 49 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME LOCATION RST WK DIR DESCRIPTION Determines the number of ADC cycles in the ADC decimation FIR filter. PLL_FAST = 1: FIR_LEN[1:0] 210C[2:1] 0 0 R/W FIR_LEN[1:0] ADC CYCLES 00 141 01 288 10 384 PLL_FAST = 0: FIR_LEN[1:0] ADC CYCLES 00 135 01 276 10 Not Allowed The ADC LSB size and full-scale values depend on the FIR_LEN[1:0] setting. FLSH_ ERASE[7:0] SFR 94[7:0] 0 0 W Flash Erase Initiate FLSH_ERASE is used to initiate either the Flash Mass Erase cycle or the Flash Page Erase cycle. Specific patterns are expected for FLSH_ERASE in order to initiate the appropriate Erase cycle. (default = 0x00). 0x55 = Initiate Flash Page Erase cycle. Must be proceeded by a write to FLSH_PGADR[6:0] (SFR 0xB7[7:1]). 0xAA = Initiate Flash Mass Erase cycle. Must be proceeded by a write to FLSH_MEEN and the ICE port must be enabled. Any other pattern written to FLSH_ERASE has no effect. FLSH_MEEN SFR B2[1] 0 0 W Mass Erase Enable 0 = Mass Erase disabled (default). 1 = Mass Erase enabled. Must be re-written for each new Mass Erase cycle. FLSH_PEND SFR B2[3] 0 0 R Indicates that a timed flash write is pending. If another flash write is attempted, it is ignored. FLSH_ PGADR[6:0] SFR B7[7:1] 0 0 W Flash Page Erase Address Flash Page Address (page 0 thru 63) that is erased during the Page Erase cycle. (default = 0x00). Must be re-written for each new Page Erase cycle. SFR B2[2] 0 0 Enables timed flash writes. When 1, and if CE_E = 1, flash write requests are stored in a one-element deep FIFO R/W and are executed when CE_BUSY falls. FLSH_PEND can be read to determine the status of the FIFO. If FLSH_ PSTWR = 0 or if CE_E = 0, flash writes are immediate. Program Write Enable 0 = MOVX commands refer to External RAM Space, normal operation (default). R/W 1 = MOVX @DPTR,A moves A to External Program Space (Flash) @ DPTR. This bit is automatically reset after each byte written to flash. Writes to this bit are inhibited when interrupts are enabled. FLSH_PSTWR FLSH_PWE SFR B2[0] 0 0 FLSH_RDE 2702[2] - - 2702[7:4] 0 0 FLSH_WRE 2702[1] - - IE_XFER IE_RTC1S IE_RTC1M IE_TCTEMP IE_RTCT IE_SPI IE_EEX IE_XPULSE IE_YPULSE IE_WPULSE IE_VPULSE SFR E8[0] SFR E8[1] SFR E8[2] SFR E8[3] SFR E8[4] SFR F8[7] SFR E8[7] SFR E8[6] SFR E8[5] SFR F8[4] SFR F8[3] FLSH_UNLOCK [3:0] www.maximintegrated.com 0 0 R Indicates that the flash may be read by ICE or SPI slave. FLSH_RDE = (!SECURE) R/W Must be a `2' to enable any flash modification. See the description of Flash security for more details. R Indicates that the flash may be written through ICE or SPI slave ports. Interrupt flags for external interrupts 2, 5, and 6. These flags monitor the source of the int2, int5, and int6 interrupts (external interrupts to the MPU core). These flags are set by hardware and must be cleared by the software interrupt R/W handler. The IEX2 (SFR 0xC0[1]) and IEX6 (SFR 0xC0[5]) interrupt flags are automatically cleared by the MPU core when it vectors to the interrupt handler. IEX2 and IEX6 must be cleared by writing zero to their corresponding bit positions in SFR 0xC0, while writing ones to the other bit positions that are not being cleared. Maxim Integrated 50 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME INTBITS LOCATION RST WK DIR 2707[6:0] - - R DESCRIPTION Interrupt inputs. The MPU may read these bits to see the input to external interrupts INT0, INT1, up to INT6. These bits do not have any memory and are primarily intended for debug use. MPU_DIV[2:0] 2200[2:0] 0 0 MPU clock rate is: MPU Rate = MCK Rate x 2-(2+MPU_DIV[2:0]). R/W The maximum value for MPU_DIV[2:0] is 4. Based on the default values of the PLL_FAST bit and MPU_DIV[2:0], the power up MPU rate is 6.29MHz/4 = 1.5725MHz. The minimum MPU clock rate is 38.4kHz when PLL_FAS T = 1. MUX2_SEL[3:0] 2104[3:0] 0 0 R/W Selects which ADC input is to be converted during time slot 2. MUX3_SEL[3:0] 2104[7:4] 0 0 R/W Selects which ADC input is to be converted during time slot 3. MUX4_SEL[3:0] 2103[3:0] 0 0 R/W Selects which ADC input is to be converted during time slot 4. MUX5_SEL[3:0] 2103[7:4] 0 0 R/W Selects which ADC input is to be converted during time slot 5. MUX6_SEL[3:0] 2102[3:0] 0 0 R/W Selects which ADC input is to be converted during time slot 6. MUX7_SEL[3:0] 2102[7:4] 0 0 R/W Selects which ADC input is to be converted during time slot 7. MUX8_SEL[3:0] 2101[3:0] 0 0 R/W Selects which ADC input is to be converted during time slot 8. MUX9_SEL[3:0] 2101[7:4] 0 0 R/W Selects which ADC input is to be converted during time slot 9. MUX10_SEL[3:0] 2100[3:0] 0 0 R/W Selects which ADC input is to be converted during time slot 10. MUX_DIV[3:0] 2100[7:4] 0 0 R/W MUX_DIV[3:0] is the number of ADC time slots in each MUX frame. The maximum number of time slots is 11. PB_STATE SFR F8[0] 0 0 R PERR_RD PERR_WR SFR FC[6] SFR FC[5] 0 0 R/W PLL_OK SFR F9[4] 0 0 R 2200[4] 0 0 210A[7:0] FF PLL_FAST PLS_ MAXWIDTH[7:0] The de-bounced state of the PB pin. The IC sets these bits to indicate that a parity error on the remote sensor has been detected. Once set, the bits are remembered until they are cleared by the MPU. Indicates that the clock generation PLL is settled. Controls the speed of the PLL and MCK. R/W 1 = 19.66 MHz (XTAL x 600) 0 = 6.29MHz (XTAL x 192) FF R/W PLS_MAXWIDTH[7:0] determines the maximum width of the pulse (low-going pulse if PLS_INV = 0 or high-going pulse if PLS_INV = 1). The maximum pulse width is (2 x PLS_MAXWIDTH[7:0] + 1) x TI. Where TI is PLS_ INTERVAL[7:0] in units of CK_FIR clock cycles. If PLS_INTERVAL[7:0] = 0 or PLS_MAXWIDTH[7:0] = 255, no pulse width checking is performed and the output pulses have 50% duty cycle. 210B[7:0] 0 0 PLS_INTERVAL[7:0] determines the interval time between pulses. The time between output pulses is PLS_ INTERVAL[7:0] x 4 in units of CK_FIR clock cycles. If PLS_INTERVAL[7:0] = 0, the FIFO is not used and pulses are output as soon as the CE issues them. PLS_INTERVAL[7:0] is calculated as follows: PLS_INTERVAL[7:0] = Floor ( Mux frame duration in CK_FIR cycles/ R/W CE pulse updates per Mux frame/4 ) For example, since the 71M654xT CE code is written to generate 6 pulses in one integration interval, when the FIFO is enabled (i.e., PLS_INTERVAL[7:0] 0) and that the frame duration is 1950 CK_FIR clock cycles, PLS_INTERVAL[7:0] should be written with Floor(1950/6/4) = 81 so that the five pulses are evenly spaced in time over the integration interval and the last pulse is issued just prior to the end of the interval. PLS_INV 210C[0] 0 0 R/W Inverts the polarity of WPULSE, VARPULSE, XPULSE and YPULSE. Normally, these pulses are active low. When inverted, they become active high. PORT_E 270C[5] 0 0 R/W Enables outputs from the pins DIO0-DIO14. PORT_E = 0 after reset and power-up blocks the momentary output pulse that would occur on DIO0 to DIO14. PQ[20:0] 2886[4:0] 2887[7:0] 2888[7:0] 0 0 R PLS_ INTERVAL[7:0] www.maximintegrated.com Temperature compensation value computed by the quadratic compensation formula. Maxim Integrated 51 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME LOCATION RST WK DIR DESCRIPTION Sets the length of the PQ mask. The mask is ANDed with the last four bits of PQ according to the table below. PQMASK also determines the length of PULSE_AUTO in TMUX. PQMASK PRE_E 2511[2:0] 0 0 R/W PQMASK MASK PULSE_AUTO WIDTH 000 0000 1s 001 1000 2s 010 1100 4s 011 1110 8s 100 1111 16s 2704[5] 0 0 PREBOOT SFRB2[7] - - R RCMD[4:0] SFR FC[4:0] 0 0 R/W RESET 2200[3] 0 0 W RFLY_DIS 210C[3] 0 0 R/W RMT2_E 2709[3] 0 0 R/W Enables the remote interface. RMT4_E 2709[4] 0 0 R/W Enables the remote interface. R/W Enables the remote interface. RMT6_E R/W Enables the 8x preamplifier. Indicates that preboot sequence is active. When the MPU writes a non-zero value to RCMD[4:0], the IC issues a command to the appropriate remote sensor. When the command is complete, the IC clears RCMD[4:0]. When set, writes a one to WF_RSTBIT and then causes a reset. Controls how the IC drives the power pulse for the 71M6x03. When set, the power pulse is driven high and low. When cleared, it is driven high followed by an open circuit fly-back interval. 2709[5] 0 0 2602[7:0] 2603[7:0] 0 0 R RTC_FAIL 2890[4] 0 0 R/W Indicates that a count error has occurred in the RTC and that the time is not trustworthy. This bit can be cleared by writing a 0. RTC_RD 2890[6] 0 0 R/W Freezes the RTC shadow register so it is suitable for MPU reads. When RTC_RD is read, it returns the status of the shadow register: 0 = up to date, 1 = frozen. RTC_SBSC[7:0] 2892[7:0] - - R RTC_TMIN[5:0] 289E[5:0] 0 - R/W The target minutes register. See RTC_THR below. RTC_THR[4:0] 289F[4:0] 0 - R/W 2890[7] 0 0 Freezes the RTC shadow register so it is suitable for MPU writes. When RTC_WR is cleared, the contents of the R/W shadow register are written to the RTC counter on the next RTC clock (~500 Hz). When RTC_WR is read, it returns 1 as long as RTC_WR is set. It continues to return one until the RTC counter actually updates. 2893[5:0] 2894[5:0] 2895[4:0] 2896[2:0] 2897[4:0] 2898[3:0] 2899[7:0] - - - - - - - - - - - - - - The RTC interface registers. These are the year, month, day, hour, minute and second parameters for the RTC. The RTC is set by writing to these registers. Year 00 and all others divisible by 4 are defined as a leap year. SEC 00 to 59 MIN 00 to 59 HR 00 to 23 (00 = Midnight) R/W DAY 01 to 07 (01 = Sunday) DATE 01 to 31 MO 01 to 12 YR 00 to 99 Each write operation to one of these registers must be preceded by a write to 0x20A0. 2106[1] 0 0 R/W Real Time Monitor enable. When 0, the RTM output is low. 210D[1:0] 210E[7:0] 210F[7:0] 2110[7:0] 2111[7:0] 0 0 0 0 0 0 0 0 0 0 Four RTM probes. Before each CE code pass, the values of these registers are serially output on the RTM pin. The R/W RTM registers are ignored when RTM_E = 0. Note that RTM0 is 10 bits wide. The others assume the upper two bits are 00. RMT_RD[15:8] RMT_RD[7:0] RTC_WR RTC_SEC[5:0] RTC_MIN[5:0] RTC_HR[4:0] RTC_DAY[2:0] RTC_DATE[4:0] RTC_MO[3:0] RTC_YR[7:0] RTM_E RTM0[9:8] RTM0[7:0] RTM1[7:0] RTM2[7:0] RTM3[7:0] www.maximintegrated.com Response from remote read request. Time remaining until the next 1 second boundary. LSB = 1/256 second. The target hours register. The RTC_T interrupt occurs when RTC_MIN becomes equal to RTC_TMIN and RTC_HR becomes equal to RTC_THR. Maxim Integrated 52 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME LOCATION RST WK DIR DESCRIPTION SBASE:[10:0] 2519[2:0] 251A[7:0] 0 0 R/W Base temperature for limit checking SECURE SFR B2[6] 0 0 R/W SFILT 251D[3:0] 0 0 R/W Filter variable for wake on temperature extremes. SLEEP 28B2[7] 0 0 W 2112[3:0] 0 0 R/S SMAX[6:0] 251B[6:0] 0 0 R/W Maximum temperature for limit checking SMIN[6:0] 251C[6:0] 0 0 R/W Minimum temperature for limit checking SLOT_EXT[3:0] SPI_CMD[7:0] R Inhibits erasure of page 0 and flash addresses above the beginning of CE code as defined by CE_LCTN[5:0]. Also inhibits the read of flash via the SPI and ICE port. Puts the part to SLP mode. Ignored if system power is present. The part wakes when the Wake timer expires, when push button is pushed, or when system power returns. If non-zero, will extend the duration of time slot zero by up to 15 extra crystal cycles. The ADC result for time slot zero will be left-shifted nine bits if SLOT_EXT=0 and four bits if SLOT_EXT0. SFR FD[7:0] - - SPI_E 270C[4] 1 1 R/W SPI port enable. SPI command register for the 8-bit command from the bus master. SPI_SAFE 270C[3] 0 0 R/W Limits SPI writes to SPI_CMD and a 16-byte region in DRAM. No other writes are permitted. SPI_STAT[7:0] 2708[7:0] 0 0 R SPI_STAT contains the status results from the previous SPI transaction. Bit 7: Ready error: The 71M654xT was not ready to read or write as directed by the previous command. Bit 6: Read data parity: This bit is the parity of all bytes read from the 71M654xT in the previous command. Does not include the SPI_STAT byte. Bit 5: Write data parity: This bit is the overall parity of the bytes written to the 71M654xT in the previous command. It includes CMD and ADDR bytes. Bit 4-2: Bottom 3 bits of the byte count. Does not include ADDR and CMD bytes. One, two, and three byte instructions return 111. Bit 1: SPI FLASH mode: This bit is zero when the TEST pin is zero. Bit 0: SPI FLASH mode ready: Used in SPI FLASH mode. Indicates that the flash is ready to receive another write instruction. STEMP[15:0] 2881[7:0] 2882[7:0] - - R The result of the temperature measurement. SUM_SAMPS[12:8] SUM_SAMPS[7:0] 2107[4:0] 2108[7:0] 0 0 R/W The number of multiplexer cycles per XFER_BUSY interrupt. Maximum value is 8191 cycles. TC_A[9:0] 2508[1:0] 2509[7:0] 0 0 R/W Temperature compensation factor for quadratic compensation. TC_B[11:0] 250A[3:0] 205B[7:0] 0 0 R/W Temperature compensation factor for quadratic compensation. TC_C[11:0] 289C[3:0] 289D[7:0] 0 0 R/W Temperature compensation factor for quadratic compensation. TEMP_22[12:8] TEMP_22[7:0] 230A[4:0] 230B[7:0] 0 - TEMP_BAT 28A0[4] 0 - R/W Causes VBAT to be measured whenever a temperature measurement is performed. TEMP_BSEL 28A0[7] 0 - R/W Selects which battery is monitored by the temperature sensor: 1 = VBAT, 0 = VBAT_RTC TBYTE_BUSY 28A0[3] 0 0 www.maximintegrated.com R R Storage location for STEMP at 22NC. STEMP is an 11-bit word. Indicates that hardware is still writing the 0x28A0 byte. Additional writes to this byte will be locked out while it is one. Write duration could be as long as 6ms. Maxim Integrated 53 71M6545T/71M6545HT Energy Meter ICs Table 13. I/O RAM Locations in Alphabetical Order (continued) NAME LOCATION RST WK DIR DESCRIPTION Sets the period between temperature measurements. Automatic measurements can be enabled in any mode (MSN, BRN, or SLP). TEMP_PER = 0 disables automatic temperature updates, in which case TEMP_START may be used by the MPU to initiate a one-shot temperature measurement. TEMP_PER TEMP_PER[2:0] 28A0[2:0] 0 - 0 R/W 1-6 7 TIME (s) No temperature updates 2(3+TEMP_PER) Continuous updates In automatic mode, TEMP_START is the indicator of the temperature sensor status: TEMP_START = 1 (temperature sensor is busy, cannot measure temperature) TEMP_START = 0 (temperature sensor is idle, can measure temperature) TEMP_PWR 28A0[6] 0 - Selects the power source for the temp sensor: R/W 1 = VV3P3D, 0 = VBAT_RTC. This bit is ignored in SLP mode, where the temp sensor is always powered by VBAT_RTC. 28B4[6] 0 0 When TEMP_PER = 0 automatic temperature measurements are disabled, and TEMP_START may be set by the MPU to initiate a one-shot temperature measurement. TEMP_START is ignored in SLP mode. Hardware clears TEMP_START when the temperature measurement is complete. R/W In automatic mode, TEMP_START is the indicator of the temperature sensor status: TEMP_START = 1 (temperature sensor is busy, cannot measure temperature) TEMP_START = 0 (temperature sensor is idle, can measure temperature) TMUX[5:0] 2502[5:0] - - R/W Selects one of 32 signals for TMUXOUT. TMUX2[4:0] 2503[4:0] - - R/W Selects one of 32 signals for TMUX2OUT. TMUXRA[2:0] 270A[2:0] TEMP_START 000 000 R/W The TMUX setting for the remote isolated sensor (71M6x03). VREF_CAL 2704[7] 0 0 R/W Brings the ADC reference voltage out to the VREF pin. This feature is disabled when VREF_DIS=1. VREF_DIS 2704[6] 0 1 R/W Disables the internal ADC voltage reference. This word describes the source of power and the status of VDD. VSTAT[2:0] WAKE_ARM SFR F9[2:0] - - R 000 System Power OK. VV3P3A>3.0v. Analog modules are functional and accurate. [V3AOK,V3OK] = 11 001 System Power Low. 2.8v<VV3P3A<3.0v. Analog modules not accurate. Switchover to battery power is imminent. [V3AOK,V3OK] = 01 010 Battery power and VDD OK. VDD>2.25v. Full digital functionality. [V3AOK,V3OK] = 00, [VDDOK,VDDgt2] = 11 011 Battery power and VDD>2.0. Flash writes are inhibited. If the TRIMVDD[5] fuse is blown, PLL_FAST (I/O RAM 0x2200[4]) is cleared. [V3AOK,V3OK] = 00, [VDDOK,VDDgt2] = 01 101 Battery power and VDD<2.0. When VSTAT=101, processor is nearly out of voltage. Processor failure is imminent. [V3AOK,V3OK] = 00, [VDDOK,VDDgt2] = 00 Arms the WAKE timer and loads it with WAKE_TMR[7:0]. When SLEEP or LCD_ONLY is asserted by the MPU, the WAKE timer becomes active. 28B2[5] 0 - R/W 2880[7:0] 0 - R/W Timer duration is WAKE_TMR+1 seconds. WD_RST 28B4[7] 0 0 W Reset the WD timer. The WD is reset when a 1 is written to this bit. Writing a one clears and restarts the watch dog timer. WF_DIO4 28B1[2] 0 - R DIO4 wake flag bit. If DIO4 is configured to wake the part, this bit is set whenever the de-bounced version of DIO4 rises. It is held in reset if DI04 is not configured for wakeup. WF_DIO55 28B1[0] 0 - R DIO55 wake flag bit. If DIO55 is configured to wake the part, this bit is set whenever the de-bounced version of DIO55 rises. It is held in reset if DI055 is not configured for wakeup. WF_TEMP 28B1[6] 0 - R Indicates that the temperature range check hardware caused the part to wake up. WAKE_TMR[7:0] www.maximintegrated.com Maxim Integrated 54 71M6545T/71M6545HT NAME Energy Meter ICs LOCATION RST WK DIR DESCRIPTION Arms the WAKE timer and loads it with WAKE_TMR[7:0]. When SLEEP or LCD_ONLY is asserted by the MPU, the WAKE timer becomes active. WAKE_ARM 28B2[5] 0 - R/W WF_PB 28B1[3] - - R Indicates that the PB caused the part to wake. WF_RX 28B1[4] 0 - R Indicates that RX caused the part to wake. WF_CSTART WF_RST WF_RSTBIT WF_OVF WF_ERST WF_BADVDD 28B0[7] 28B0[6] 28B0[5] 28B0[4] 28B0[3] 28B0[2] 0 1 0 0 0 0 - R Indicates that the Reset pin, Reset bit, ERST pin, Watchdog timer, the cold start detector, or bad VBAT caused the part to reset. CE Interface Description CE Program The CE performs the precision computations necessary to accurately measure energy. These computations include offset cancellation, phase compensation, product smoothing, product summation, frequency detection, VAR calculation, sag detection and voltage phase measurement. The CE program is supplied by Maxim Integrated as a data image that can be merged with the MPU operational code for meter applications. Typically, the CE program provided with the demonstration code covers most applications and does not need to be modified. Other variations of CE code are available. Contact your local Maxim Integrated representative to obtain the appropriate CE code required for a specific application. CE Data Format All CE words are 4 bytes. Unless specified otherwise, they are in 32-bit two's complement format (-1 = 0xFFFFFFFF). Calibration parameters are defined in flash memory (or external EEPROM) and must be copied to CE data memory by the MPU before enabling the CE. Internal variables are used in internal CE calculations. Input variables allow the MPU to control the behavior of the CE code. Output variables are outputs of the CE calculations. The corresponding MPU address for the most significant byte is given by 0x0000 + 4 x CE_address and by 0x0003 + 4 x CE_address for the least significant byte. Constants * VMAX: RMS voltage corresponding to 250mV peak at the VA and VB inputs. * NACC: Accumulation count for energy measurements is SUM_SAMPS[12:0]. The duration of the accumulation interval for energy measurements is SUM_ SAMPS[12:0]/FS. * X: Gain constant of the pulse generators. Its value is determined by PULSE_FAST and PULSE_SLOW. * Voltage LSB (for sag threshold) = VMAX x 7.8798 x10-9 V. The system constants IMAX and VMAX are used by the MPU to convert internal digital quantities (as used by the CE) to external, i.e., metering quantities. Their values are determined by the scaling of the voltage and current sensors used in an actual meter. Environment Before starting the CE using the CE_E bit (I/O RAM 0x2106[0]), the MPU has to establish the proper environment for the CE by implementing the following steps: * Locate the CE code in flash memory using CE_LCTN[5:0]. * Load the CE data into RAM. * Establish the equation to be applied in EQU[2:0]. * Establish the number of samples per accumulation period in SUM_SAMPS[12:0]. * Establish the number of cycles per ADC multiplexer frame (MUX_DIV[3:0]). * Apply proper values to MUXn_SEL, as well as proper selections for DIFFn_E and RMT_E in order to configure the analog inputs. * Sampling Frequency: 2520.62Hz. * F0: Frequency of the mains phases (typically 50Hz or 60Hz). * * IMAX: RMS current corresponding to 250mV peak (176.8 mVRMS) at the inputs IA and IB. IMAX needs to be adjusted if the preamplifier is activated for the IAP-IAN inputs. For a 250 shunt resistor, IMAX becomes 707A (176.8 mVRMS/250FI = 707.2ARMS). Initialize any MPU interrupts, such as CE_BUSY, XFER_BUSY, or the power failure detection interrupt. * VMAX = 600V, IMAX = 707A, and kH = 1Wh/pulse are assumed as default settings www.maximintegrated.com When different CE codes are used, a different set of environment parameters need to be established. The exact Maxim Integrated 55 71M6545T/71M6545HT values for these parameters are listed in the Application Notes and other documentation which accompanies the CE code. The CE details described in this data sheet should be considered typical and may not, in aggregate, be indicative of any particular CE code. Contact your Maxim Integrated representative for details about available standard CE codes. CE Calculations The MPU selects the basic configuration for the CE by setting the EQU variable. CE Input Data Data from the AFE is placed into CE memory by hardware at ADC0-ADC10. Table 15 describes the process. Status and Control The CESTATUS register (0x80) contains bits that reflect the status of the signals that are applied to the CE. CECONFIG (0x20) contains bits that control basic operation of the compute engine. The CE code supports registers to establish the sag threshold and gain for each of the input channels. When the input RMS voltage level falls below an established level, a warning is posted to the MPU. This level is called the sag threshold, and it is set in the SAG_THR register. Gain for each channel is adjusted in the GAIN_ADJ0 (voltage), GAIN_ADJ1 (current channel A) and GAIN_ ADJ2 (current channel B). Transfer Variables After each pass through CE program code, the CE asserts a XFER_BUSY interrupt. This informs the MPU that new data is available. It is the responsibility of MPU code to retrieve the data from the CE in a timely manner. Pulse Generation WRATE (CE RAM 0x21) along with the PULSE_SLOW and PULSE_FAST bits control the number of pulses that www.maximintegrated.com Energy Meter ICs are generated per measured Wh and VARh quantities. The pulse rate is proportional to the WRATE value for a given energy. The meter constant Kh is derived from WRATE as the amount of energy measured for each pulse. That is, if Kh = 1Wh/pulse, a power applied to the meter of 120 V and 30 A results in one pulse per second; if the load is 240 V at 150 A, ten pulses per second are generated. Normally, the CE takes the values from W0SUM_X and VAR0SUM_X and moves them to APULSEW and APULSER, respectively. Then, pulse generation logic in the CE creates the actual pulses. However, the MPU can take direct control of the pulse generation process by setting EXT_PULSE = 1. In this case, the MPU sets the pulse rate by directly loading APULSEW and APULSER. Note that since creep management is an MPU function, when the CE manages pulse output (EXT_PULSE = 0) creep management is disabled. The maximum pulse rate is 3 x FS = 7.56kHz. The maximum time jitter is 1/6 of the multiplexer cycle period (nominally 67s) and is independent of the number of pulses measured. Thus, if the pulse generator is monitored for one second, the peak jitter is 67ppm. After 10 seconds, the peak jitter is 6.7ppm. The average jitter is always zero. If it is attempted to drive either pulse generator faster than its maximum rate, it simply outputs at its maximum rate without exhibiting any rollover characteristics. The actual pulse rate, using WSUM as an example, is: WRATE WSUM FS X RATE = Hz 2 46 where FS = sampling frequency (2520.6 Hz), X = Pulse speed factor derived from the CE variables PULSE_ SLOW and PULSE_FAST. Figure 17, Figure 18, and Figure 19 show the data flow through the CE in simplified form. Functions not shown include delay compensation, sag detection, scaling, and the processing of meter equations. Maxim Integrated 56 71M6545T/71M6545HT Energy Meter ICs CE Flow Diagrams Table 14. Power Equations EQU[2:0] WATT AND VAR FORMULA (WSUM/VARSUM) W0SUM/ VAR0SUM W1SUM/ VAR1SUM W2SUM/ VAR2SUM I0SQ SUM I1SQ SUM I2SQ SUM 3 VA x (IA-IB/2) + VC x IC (2 element 4W 3<phi>Delta) VA x (IA-IB)/2 -- VC x IC IA-IB IB IC 4 VA x (IA-IB)/2 + VB(IC-IB)/2 (2 element 4W 3<phi>Wye) VA x (IA-IB)/2 VB x (IC-IB) -- IA-IB IC-IB IC 5 VA x IA+VB x IB + VC x IC (3 element 4W 3<ph> Wye) VA x IA VB x IB VC x IC IA IB IC Table 15. CE Raw Data Access Locations PIN MUXn_SEL HANDLE CE RAM LOCATION DIFF0_E 0 IADC0 0 IADC1 1 DIFF0_E 1 0 0 0 1 RMT2_E, DIFF2_E 0,0 IADC2 2 IADC3 3 0,1 2 1,0 - IADC4 4 IADC5 5 1,1 - 0,0 2 3 IADC6 6 IADC7 7 0,1 1,0 1,1 2 2* 2* RMT4_E, DIFF4_E 0,1 1,0 1,1 4 - - 0,0 4 5 RMT6_E, DIFF6_E 0,0 0 RMT2_E, DIFF2_E RMT4_E, DIFF4_E 0,0 1 0,1 1,0 1,1 4 4* 4* RMT6_E, DIFF6_E 0,1 1,0 1,1 6 - - 0,0 6 7 0,1 1,0 1,1 6 6* 6* There are no configuration bits for VADC8, 9, 10 VADC8 (VA) 8 8 VADC9 (VB) 9 9 VADC10 (VC) 10 10 *Remote interface data. www.maximintegrated.com Maxim Integrated 57 71M6545T/71M6545HT Energy Meter ICs Table 16. CE Status Register CESTATUS BIT NAME 31:4 Not used DESCRIPTION 3 F0 2 SAG_C Normally zero. Becomes one when VB remains below SAG_THR for SAG_CNT samples. Does not return to zero until VB rises above SAG_THR. 1 SAG_B Normally zero. Becomes one when VB remains below SAG_THR for SAG_CNT samples. Does not return to zero until VB rises above SAG_THR. 0 SAG_A Normally zero. Becomes one when VA remains below SAG_THR for SAG_CNT samples. Does not return to zero until VA rises above SAG_THR. These unused bits are always zero. F0 is a square wave at the exact fundamental input frequency. Table 17. CE Configuration Register CECONFIG BIT NAME DEFAULT DESCRIPTION 22 EXT_TEMP 0 When 1, the MPU controls temperature compensation through the GAIN_ADJn registers (CE RAM 0x40-0x42), when 0, the CE is in control. 21 EDGE_INT 1 When 1, XPULSE produces a pulse for each zero-crossing of the mains phase selected by FREQSEL[1:0] , which can be used to interrupt the MPU. 20 SAG_INT 1 When 1, activates YPULSE output when a sag condition is detected. 19:8 SAG_CNT 252 (0xFC) The number of consecutive voltage samples below SAG_THR (CE RAM 0x24) before a sag alarm is declared. The default value is equivalent to 100 ms. FREQSEL[1:0] selects the phase to be used for the frequency monitor, sag detection, and for the zero crossing counter (MAINEDGE_X). 7:6 FREQSEL[1:0] FREQ SEL[1:0] 0 PHASE SELECTED 0 0 A 0 1 B* 1 X Not allowed 5 EXT_PULSE 1 When zero, causes the pulse generators to respond to internal data (WPULSE = WSUM_X, VPULSE = VARSUM_X). Otherwise, the generators respond to values the MPU places in APULSEW and APULSER. 4:2 Reserved 0 Reserved. 0 When PULSE_FAST = 1, the pulse generator input is increased 16x. When PULSE_SLOW = 1, the pulse generator input is reduced by a factor of 64. These two parameters control the pulse gain factor X (see table below). Allowed values are either 1 or 0. Default is 0 for both (X = 6). 1 0 PULSE_FAST PULSE_SLOW www.maximintegrated.com 0 PULSE_FAST PULSE_SLOW X 0 0 1.5 x 22 = 6 1 0 1.5 x 26 = 96 0 1 1.5 x 2-4 = 0.09375 1 1 Do not use Maxim Integrated 58 71M6545T/71M6545HT Energy Meter ICs Table 18. Sag Threshold and Gain Adjustment Registers CE ADDRESS 0x24 NAME SAG_THR DEFAULT 2.39 x 107 DESCRIPTION The voltage threshold for sag warnings. The default value is equivalent to 113V peak or 80 VRMS if VMAX = 600VRMS. SAG_THR = VRMS 2 VMAX 7.8798 10 -9 0x40 GAIN_ADJ0 16384 This register scales the voltage measurement channels VADC8 (VA), VADC9 (VB) AND VADC10 (VC). The default value of 16384 is equivalent to unity gain (1.000). 0x41 GAIN_ADJ1 16384 This register scales the neutral current channel for neutral current. The default value of 16384 is equivalent to unity gain (1.000). 0x42 GAIN_ADJ2 16384 This register scales the IA current channel for Phase A. The default value of 16384 is equivalent to unity gain (1.000). 0x43 GAIN_ADJ3 16384 This register scales the IB current channel for Phase B. The default value of 16384 is equivalent to unity gain (1.000). 0x44 GAIN_ADJ4 16384 This register scales the IC current channel for Phase C. The default value of 16384 is equivalent to unity gain (1.000). Table 19. CE Transfer Registers CE ADDRESS NAME 0x84 WSUM_X The signed sum: W0SUM_X+W1SUM_X. Not used for EQU[2:0] = 0 and EQU[2:0] = 1. DESCRIPTION 0x85 W0SUM_X 0x86 W1SUM_X 0x87 W2SUM_X The sum of Wh samples from each wattmeter element. LSB = 9.4045 x 10-13 x VMAX x IMAX Wh (local) LSB = 1.55124 x 10-12 x VMAX x IMAX Wh (remote) 0x88 VARSUM_X The signed sum: VAR0SUM_X+VAR1SUM_X. Not used for EQU[2:0] = 0 and EQU[2:0] = 1. The sum of VARh samples from each wattmeter element. LSB = 9.4045 x 10-13 x VMAX x IMAX VARh (local) LSB = 1.55124 x 10-12 x VMAX x IMAX VARh (remote) 0x89 VAR0SUM_X 0x8A VAR1SUM_X 0x8B VAR2SUM_X 0x8C I0SQSUM_X 0x8D I1SQSUM_X 0x8E I2SQSUM_X 0x8F I3SQSUM_X 0x90 V0SQSUM_X 0x91 V1SQSUM_X 0x92 V2SQSUM_X The sum of squared current samples from each element. LSB = 9.4045 x 10-13 IMAX2 A2h (local) LSB = 2.55872 x 10-12 x IMAX2 A2h (remote) The sum of squared voltage samples from each element. LSB= 9.4045 x 10-13 VMAX2 V2h (local) LSB= 9.40448 x 10-13 x VMAX2 V2h (remote) Fundamental frequency: 0x82 FREQ_X LSB LSB 0x83 MAINEDGE_X www.maximintegrated.com 2520.6Hz 2 32 2520.6Hz 2 32 0.509 10 -6 Hz (for Local) 0.587 10 -6 Hz (for Remote) The number of edge crossings of the selected voltage in the previous accumulation interval. Edge crossings are either direction and are debounced. Maxim Integrated 59 71M6545T/71M6545HT Energy Meter ICs Table 20. CE Pulse Generation Parameters CE ADDRESS NAME DEFAULT DESCRIPTION = Kh VMAX IMAX K Wh / pulse WRATE N ACC X 0x21 WRATE 547 0x22 KVAR 6444 where: K = 66.1782 (Local Sensors) K = 109.1587 (Remote Sensor) NACC = SUM_SAMPS[12:0] (CE RAM 0x23) X is a factor determined by PULSE_FAST and PULSE_SLOW. See CECONFIG definition for more information The default value yields 1.0 Wh/pulse for VMAX = 600 V and IMAX = 208 A. The maximum value for WRATE is 32,768 (215). Scale factor for VAR measurement. 0x23 SUM_SAMPS 2520 SUM_SAMPS (NACC). 0x45 APULSEW 0 Wh pulse (WPULSE) generator input to be updated by the MPU when using external pulse generation. The output pulse rate is: APULSEW x fS x 2-32 * WRATE x X x 2-14. This input is buffered and can be updated by the MPU during a conversion interval. The change takes effect at the beginning of the next interval. 0x46 WPULSE_CTR 0 WPULSE counter. 0x47 WPULSE_FRAC 0 Unsigned numerator, containing a fraction of a pulse. The value in this register always counts up towards the next pulse. 0x48 WSUM_ACCUM 0 Roll-over accumulator for WPULSE. 0x49 APULSER 0 VARh (VPULSE) pulse generator input. 0x4A VPULSE_CTR 0 VPULSE counter. 0x4B VPULSE_FRAC 0 Unsigned numerator, containing a fraction of a pulse. The value in this register always counts up towards the next pulse. 0x4C VSUM_ACCUM 0 Roll-over accumulator for VPULSE. www.maximintegrated.com Maxim Integrated 60 71M6545T/71M6545HT Energy Meter ICs Table 21. Other CE Parameters CE ADDRESS NAME DEFAULT 0x25 QUANT_VA 0 0x26 QUANT_IA 0 0x27 QUANT_A 0 0x28 QUANT_VARA 0 0x29 QUANT_VB 0 0x2A QUANT_IB 0 0x2B QUANT_B 0 0x2C QUANT_VARB 0 0x2D QUANT_VC 0 0x2E QUANT_IC 0 0x2F QUANT_C 0 0x30 QUANT_VARC 0 0x38 0x43453431 0x39 0x6130316B 0x3A 0x00000000 DESCRIPTION Compensation factors for truncation and noise in voltage, current, real energy and reactive energy for phase A. Compensation factors for truncation and noise in voltage, current, real energy and reactive energy for phase B. Compensation factors for truncation and noise in voltage, current, real energy and reactive energy for phase C. CE file name identifier in ASCII format (CE41a01f). These values are overwritten as soon as the CE starts LSB weights for use with Local Sensors: QUANT_Ix_LSB = 5.08656 * 10-13 * IMAX2 (Amps2) QUANT_Wx_LSB = 1.04173 * 10-9 * VMAX * IMAX (Watts) QUANT_VARx_LSB = 1.04173 * 10-9 * VMAX * IMAX (Vars) LSB weights for use with the 71M6x03 isolated sensors: QUANT_Ix_LSB = 1.38392 * 10-12 * IMAX2 (Amps2) QUANT_Wx_LSB = 1.71829 * 10-9 * VMAX * IMAX (Watts) QUANT_VARx_LSB = 1.71829 * 10-9 * VMAX * IMAX (Vars) www.maximintegrated.com Maxim Integrated 61 71M6545T/71M6545HT Energy Meter ICs Table 22. CE Calibration Parameters CE ADDRESS NAME DEFAULT 0x10 CAL_IA 16384 0x11 CAL_VA 16384 0x13 CAL_IB 16384 0x14 CAL_VB 16384 0x12 PHADJ_A 0 0x15 PHADJ_B 0 0x18 PHADJ_C 0 0x12 L_COMP2_A 16384 DESCRIPTION These constants control the gain of their respective channels. The nominal value for each parameter is 214 = 16384. The gain of each channel is directly proportional to its CAL parameter. Thus, if the gain of a channel is 1% slow, CAL should be increased by 1%. Refer to the 71M6x03 Demo Board User's Manual for the equations to calculate these calibration parameters. These constants control the CT phase compensation. Compensation does not occur when PHADJ_X = 0. As PHADJ_X is increased, more compensation (lag) is introduced. The range is P 215 - 1. If it is desired to delay the current by the angle F, the equations are: PHADJ_ X = 2 20 PHADJ_ X = 2 20 0.02229 tan( F) at 60Hz 0.1487 - 0.0131 tan( F) 0.0155 tan( F) 0.1241 - 0.009695 tan( F) at 50Hz The shunt delay compensation is obtained using the equation provided below: 0x15 L_COMP2_B 16384 0x18 L_COMP2_C 16384 www.maximintegrated.com where: fS = sampling frequency f = mains frequency Maxim Integrated 62 71M6545T/71M6545HT Energy Meter ICs VREF MULTIPLEXER DE-MULTIPLEXER IA IA_RAW VA VA_RAW IB MOD VB IB_RAW DECIMATOR VB_RAW IC IC_RAW VC VC_RAW ID ID_RAW FS = 2184Hz FS = 2184Hz Figure 17. CE Data Flow--Multiplexer and ADC I0 IA_RAW OFFSET NULL PHASE COMP LPF W0 LPF VAR0 F0 CAL_IA PHADJ_0 VA_RAW V0 OFFSET NULL 90 F0 CAL_VA GAIN_ADJ F0 GENERATOR ...OTHER PHASES F0 Figure 18. CE Data Flow--Offset, Gain, and Phase Compensation www.maximintegrated.com Maxim Integrated 63 71M6545T/71M6545HT Energy Meter ICs WA WB SUM WASUM_X WBSUM_X WC MPU WCSUM_X VARASUM_X VARA VARBSUM_X VARB VARC VARCSUM_X SUM_SAMS = 2184 SQUARE IA IB IC I2 VA V2 VB VC IASQ IBSQ ICSQ IBSQSUM_X ICSQSUM_X VASQ VASQSUM_X VBSQ VBSQSUM_X VCSQ VCSQSUM_X IDSQ ID IASQSUM_X IDSQSUM_X F0 F0 Figure 19. CE Data Flow--Squaring and Summation Ordering Information PART TEMP RANGE ACCURACY (typ, %) FLASH (KB) PIN-PACKAGE 71M6545T-IGT/F -40C to +85C 0.1 64 64 LQFP 71M6545T-IGTR/F -40C to +85C 0.1 64 64 LQFP 71M6545HT-IGT/F -40C to +85C 0.1 64 64 LQFP 71M6545HT-IGTR/F -40C to +85C 0.1 64 64 LQFP F = Lead(Pb)-free/RoHS-compliant package. R = Tape and reel. Package Information For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 64 LQFP C64L+7 21-0665 90-0411 www.maximintegrated.com Maxim Integrated 64 71M6545T/71M6545HT Energy Meter ICs Typical Operating Circuit SHUNT CURRENT SENSORS C LOAD NEUTRAL B A POWER SUPPLY 71M6xx3 71M6xx3 NEUTRAL PULSE TRANSFORMERS 71M6xx3 NOTE: THIS SYSTEM IS REFERENCED TO NEUTRAL MUX AND ADC RESISTOR DIVIDERS IADC0 IN* IADC1 VADC10 (VC) IADC6 IC IADC7 VADC9 (VB) IADC4 IB IADC5 VADC8 (VA) IADC2 IA IADC3 VV3P3A VV3P3SYS 71M6545T 71M6545HT REGULATOR TEMPERATURE SENSOR BATTERY MONITOR RAM OSCILLATOR/PLL RTC BATTERY XIN 32kHz TX XOUT RX MPU RTC TIMERS FLASH MEMORY SPI INTERFACE DIO, PULSES, LEDs DIO 24 TMUX COMPUTE ENGINE WPULSE XPULSE RPULSE YPULSE PULSES XFER_BUSY DIO I2C OR WIRE EEPROM VV3P3D ICE HOST PB VBAT_RTC SERIAL PORTS SPI_CKI SPI_DI SPI_DO SPI_CSZ GNDD PWR MODE CONTROL VREF AMR GNDA 3.3VDC SAG *IN = OPTIONAL NEUTRAL CURRENT www.maximintegrated.com Maxim Integrated 65 71M6545T/71M6545HT Energy Meter ICs Revision History REVISION NUMBER REVISION DATE 0 8/13 Initial release 1 10/13 Removed "future product" status on 71M6545HT in the Ordering Information table, updated the VREF Error specification in the Electrical Characteristics 10, 62 2 12/13 Updated the CXL and CXS capacitor values from 10pF and 15pF to 22pF 12, 14 3 3/14 Updated the VREF coefficients in the Electrical Characteristics table; removed Note 2 from the EC notes; changed CXS and CXL notes in the Recommended External Components table 4 1/15 Updated the Benefits and Features section 5 12/15 Added a new Reading the Info Page section, a new Test Port table, a replacement for Table 13, and removed Table 12; updated Table 11 and Table 19; renumbered tables 10-12 accordingly; corrected land pattern number DESCRIPTION PAGES CHANGED -- 8, 10, 12 1 35, 47, 52, 54, 55, 58, 64 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim's website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. (c) 2015 Maxim Integrated Products, Inc. 66