I2CTM & SPI Real-Time Clock/Calendar Families Battery Switchover, Non-Volatile Memory, Unique Peripherals Feature Rich, Low Cost Timekeeping Solutions Microchip's Real-Time Clocks are highly integrated with non-volatile memory and cost effective features for real life applications. This includes a battery switchover with timestamp to maintain timekeeping so the time and duration of any power failure can be logged. When higher accuracy is needed, digital trimming can compensate for crystal frequencies that drift over temperature. Baseline Features for all RTCCs Timing Programmable alarm/clock output Wide digital trimming range for accuracy Timestamp @ VCC Fail and VCC Restore User Memory Battery-backed SRAM EEPROM Unique ID/MAC address Industry Standard Pinout Low Power Wide operating and backup voltages - VCC = 1.8V to 5.5V - VBAT = 1.3V to 5.5V Standby currents - ICC < 2 A @ 3V - IBAT < 700 nA @ 1.8V Backup Power - Automatic battery switchover MCP794XX I2C RTCC Features Three types of user memory - SRAM: 64 bytes - EEPROM: 0 and 1 Kbits - Unique ID: 64 bits Alarms - Counts down to the second Digital Trimming - Adjustment range of ~11 seconds/day Operating Speed - 400 kHz MCP795XX SPI RTCC Features Three types of user memory - SRAM: 64 bytes - EEPROM: 1 and 2 Kbits - Unique ID: 128 bits Alarms - Counts down to 0.01 seconds Digital trimming - Adjustment range of ~22 seconds/day Watchdog timer - Dual retriggers using SPI bus or GPIO - From 15 msec to 64 sec Event detect inputs - High speed - Programmable count - Low speed - Programmable debounce Boot clock (boot devices only) - 32 KHz clock output at powerup Operating speed - 10 MHz @ 4.5V Microchip Technology Incorporated I2CTM and SPI Real-Time Clock/Calendar Features Timing Features Digital Alarms/ Watchdog Trimming Count Timer I2CTM Real-Time Clock/Calendar (400 kHz) 127 ppm 2 MCP7941X - (+1 ppm) (1 sec) 127 ppm 2 MCP7940X - (+1 ppm) (1 sec) 127 ppm 2 MCP7940N - (+1 ppm) (1 sec) SPI Real-Time Clock/Calendar (10 MHz) Product MCP795W2X 255 ppm (+1 ppm) 2 (0.01 sec) MCP795W1X 255 ppm (+1 ppm) 2 (0.01 sec) MCP795B2X 255 ppm (+1 ppm) 2 (0.01 sec) MCP795B1X 255 ppm (+1 ppm) 2 (0.01 sec) Outputs MFP (IRQ/CLK) MFP (IRQ/CLK) MFP (IRQ/CLK) 1. 2. 3. 1. 2. 3. 1. 2. 3. 1. 2. 3. CLK IRQ WDT RST CLK IRQ WDT RST CLK IRQ WDT RST CLK IRQ WDT RST SRAM (Bytes) Memory EE (Kbits) ID/MAC (Bits) Power Fail Timestamp Unique Features Event Boot Clock Detects (32 kHz) 64 1 64 - - 64 0 64 - - 64 0 0 - - 64 2 128 - 64 1 128 - Packages 8 SOIC, 8 TSSOP, 8 MSOP 8 TDFN 14 SOIC 14 TSSOP 64 2 128 64 1 128 Note: All part numbers with an "X" have 3 ID programming options: 0 = Blank ID, 1 = EUI-48TM MAC Address, 2 = EUI-64TM MAC Address Power Fail Timestamp RTCC Development Environment RTCC PICtail Plus Daughter Boards plug into compatible development systems. MCP79410 I2CTM PICtail(R) Plus Daughter Board (AC164140) Two Event Detect Inputs (SPI RTCC) MCP795W20 SPI PICtail(R) Plus Daughter Board (AC164147) Compatible Development Tools PICDEMTM PIC18 Explorer Board (DM183032) Explorer 16 Development Board (DM240001) www.microchip.com/clock Visit our web site for additional product information and to locate your local sales office. Microchip Technology Inc. * 2355 W. Chandler Blvd. * Chandler, AZ 85224-6199 Information subject to change. The Microchip name and logo, the Microchip logo and PIC are registered trademarks and PICDEM and PICtail are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. All other trademarks mentioned herein are property of their respective companies. (c) 2011, Microchip Technology Incorporated. All Rights Reserved. Printed in the U.S.A. 11/11 DS25074A *DS25074A*