I2C™ & SPI Real-Time Clock/Calendar Families
Battery Switchover, Non-Volatile Memory, Unique Peripherals
Microchip Technology Incorporated
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
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.
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
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 μA @ 3V
– IBAT < 700 nA @ 1.8V
Backup Power
– Automatic battery switchover
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. © 2011, Microchip Technology Incorporated. All Rights Reserved. Printed in the U.S.A. 11/11
DS25074A
*DS25074A*
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
www.microchip.com/clock
I2C™ and SPI Real-Time Clock/Calendar Features
Product
Timing Features Memory Unique Features
Packages
Digital
Trimming
Alarms/
Count
Watchdog
Timer Outputs SRAM
(Bytes)
EE
(Kbits)
ID/MAC
(Bits)
Power Fail
Timestamp
Event
Detects
Boot Clock
(32 kHz)
I2C™ Real-Time Clock/Calendar (400 kHz)
MCP7941X ± 127 ppm
(+1 ppm)
2
(1 sec) –MFP
(IRQ/CLK) 64 1 64 ––
8 SOIC,
8 TSSOP,
8 MSOP
8 TDFN
MCP7940X ± 127 ppm
(+1 ppm)
2
(1 sec) –MFP
(IRQ/CLK) 64 0 64 ––
MCP7940N ± 127 ppm
(+1 ppm)
2
(1 sec) –MFP
(IRQ/CLK) 64 0 0 ––
SPI Real-Time Clock/Calendar (10 MHz)
MCP795W2X ± 255 ppm
(+1 ppm)
2
(0.01 sec)
1.
CLK
2.
IRQ
3.
WDT RST
64 2 128
–
14 SOIC
14 TSSOP
MCP795W1X ± 255 ppm
(+1 ppm)
2
(0.01 sec)
1.
CLK
2.
IRQ
3.
WDT RST
64 1 128
–
MCP795B2X ± 255 ppm
(+1 ppm)
2
(0.01 sec)
1.
CLK
2.
IRQ
3.
WDT RST
64 2 128
MCP795B1X ± 255 ppm
(+1 ppm)
2
(0.01 sec)
1.
CLK
2.
IRQ
3.
WDT RST
64 1 128
Note: All part numbers with an “X” have 3 ID programming options: 0 = Blank ID, 1 = EUI-48™ MAC Address, 2 = EUI-64™ MAC Address
RTCC Development Environment
RTCC PICtail Plus Daughter Boards plug into compatible
development systems.
Power Fail Timestamp
Two Event Detect Inputs (SPI RTCC) Compatible Development Tools
MCP795W20 SPI
PICtail® Plus
Daughter Board
(AC164147)
Explorer 16
Development Board
(DM240001)
MCP79410 I2C™
PICtail® Plus
Daughter Board
(AC164140)
PICDEM™ PIC18
Explorer Board
(DM183032)
