MCP79410/MCP79411/MCP79412 2 Battery-Backed I C Real-Time Clock/Calendar with SRAM, EEPROM and Protected EEPROM Device Selection Table Operating Ranges 2 2-Wire Serial Interface, I C Compatible: Part Number Protected EEPROM 2 -I C clock rate up to 400 kHz MCP79410 Unprogrammed Temperature Range: - Industrial (I): -40C to +85C MCP79411 EUI-48 MCP79412 EUI-64 Packages 8-Lead SOIC, MSOP, TSSOP and 2x3 TDFN Timekeeping Features General Description Real-Time Clock/Calendar (RTCC): - Hours, minutes, seconds, day of week, day, The MCP7941X Real-Time Clock/Calendar (RTCC) month, year tracks time using internal counters for hours, minutes, - Leap year compensated to 2399 seconds, days, months, years, and day of week. Alarms - 12/24-hour modes can be configured on all counters up to and including Oscillator for 32.768 kHz Crystals: months. For usage and configuration, the MCP7941X 2 - Optimized for 6-9 pF crystals supports I C communications up to 400 kHz. On-Chip Digital Trimming/Calibration: The open-drain, multi-functional output can be - 1 ppm resolution configured to assert on an alarm match, to output a selectable frequency square wave or as a general - 129 ppm range purpose output. Dual Programmable Alarms Versatile Output Pin: The MCP7941X is designed to operate using a - Clock output with selectable frequency 32.768 kHz tuning fork crystal with external crystal load capacitors. On-chip digital trimming can be used to - Alarm output adjust for frequency variance caused by crystal - General purpose output tolerance and temperature. Power-Fail Timestamp: SRAM and timekeeping circuitry are powered from the - Time logged on switchover to and from Battery backup supply when main power is lost, allowing the mode device to maintain accurate time and the SRAM contents. The times when the device switches over to Low-Power Features the back-up supply and when primary power returns are Wide Voltage Range: both logged by the power-fail timestamp. - Operating voltage range of 1.8V to 5.5V The MCP7941X features 1 Kbit of internal nonvolatile - Backup voltage range of 1.3V to 5.5V EEPROM with software write-protectable regions. There Low Typical Timekeeping Current: is an additional 64 bits of protected nonvolatile memory - Operating from VCC: 1.2 A at 3.3V which is only writable after an unlock sequence, making - Operating from VBAT: 925 nA at 3.0V it ideal for storing a unique ID or other critical information. The MCP79411 and MCP79412 are Automatic Switchover to Battery Backup preprogrammed with EUI-48 and EUI-64 addresses, respectively. Custom programming is also available. User Memory Package Types 64-Byte Battery-Backed SRAM 1 Kbit EEPROM Memory: SOIC, TSSOP, MSOP - Software write-protect TDFN - Page write up to eight bytes X1 1 8 VCC X1 1 8 VCC - Endurance: 1M Erase/Write cycles X2 2 7 MFP X2 2 7 MFP 64-Bit Protected EEPROM Area: VBAT3S6CL V 3 6 SCL BAT - Robust write unlock sequence VSS 4 5 SDA VSS 4 5 SDA -EUI-48 MAC address (MCP79411) -EUI-64 MAC address (MCP79412) 2010-2018 Microchip Technology Inc. DS20002266J-page 1MCP79410/MCP79411/MCP79412 FIGURE 1-1: TYPICAL APPLICATION SCHEMATIC VCC VCC VCC 8 VCC C 1 X1 X1 6 SCL M PIC MCU C 5 2 X2 SDA X2 7 3 MFP VBAT VBAT VSS 4 FIGURE 1-2: BLOCK DIAGRAM VCC Power Control Power-Fail VSS and Switchover Timestamp VBAT SCL Control Logic Configuration 2 I C Interface and Addressing SDA Seconds SRAM EEPROM Minutes X1 32.768 kHz Hours Clock Divider Oscillator X2 Day of Week Digital Trimming Date Square Wave Month Alarms Output Year MFP Output Logic 2010-2018 Microchip Technology Inc. DS20002266J-page 2 32.768 KHZ