RTCCs include battery switchover, digital trimming and SRAM

MICROCHIP MCP7940N Stand-alone real-time clock/calendars (RTCCs) provides battery switchover and timestamp for accurate timekeeping, digital trimming for time-of-day calibration and 64 bytes of SRAM. Devices provide a lower-cost alternative to the existing MCP7941X devices, which feature 1Kbit of EEPROM memory and a 64-bit reprogrammable unique ID.

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