The MCP79521 SPI RTCC is highly integrated with memory and advanced features normally found in higher priced devices. By starting with a basic real-time clock, digital trimming was added for higher accuracy, a battery switchover for backup power, a timestamp to log power failures and three types of memory, which includes SRAM, EEPROM and a unique ID in a locked section of EEPROM. This ID is preprogrammed with a 48-bit MAC Address, but it can also be ordered blank for the end user to program.

General purpose SPI RTCC with features that target low power, security & communicationsapplications.

  Low Power Operation

  VCC Min = 1.8V

  Icc

  Low Backup Power

  VBAT Min = 1.3V

  Ibat

  Automatic Battery Switchover with Timestamp

  VCC to VBAT (VCC Lost)

  VBAT to VCC (VCC Restored)

  Dual configurable alarms with a 0.01 sec count on one alarm

  IRQ (VCC or VBAT)

  Clock Out frequencies: 32.768, 8.192 & 4.096 KHz and 1 Hz

  Digital Trimming Range from -255 to + 255 ppm in 1 ppm steps

  Adjusts up to 22 seconds/day

  EEPROM has 8 Bytes/Page with Block Sector write protection

  Protect: None, 1/4, 1/2 or all of array

  Factory standard MAC address programming or custom ID available