The MCP7940N's real-time clock/calendar (RTCC) tracks time with internal counters for hours, minutes, Seconds, days, months, years, and the day of the week. Alarms can be applied to all counters up to and including months. For use and configuration, the MCP7940N supports I2C communication up to 400 kHz. The open-drain multifunction output can be configured to be one in case of an alarm match Selectable frequency square wave or as a general purpose output. The MCP7940N is for operation with a 32.768 kHz tuning fork crystal with external quartz load capacitors. The digital on-chip trim can be used frequency deviations due to quartz tolerance and tolerance and temperature. https://elecena.pl/product/21709875/mcp7940n-i-ms-real-time-clock-clock-calendar-i2c-msop-8 2022-09-28 https://elecena.pl/product/21709875/mcp7940n-i-ms-real-time-clock-clock-calendar-i2c-msop-8 2022-10-20 https://elecena.pl/product/21709875/mcp7940n-i-ms-real-time-clock-clock-calendar-i2c-msop-8 2023-02-05 https://elecena.pl/product/21709875/mcp7940n-i-ms-real-time-clock-clock-calendar-i2c-msop-8 2023-10-02 https://elecena.pl/product/21709875/mcp7940n-i-ms-real-time-clock-clock-calendar-i2c-msop-8 2025-12-26 https://elecena.pl/product/21709875/mcp7940n-i-ms-real-time-clock-clock-calendar-i2c-msop-8 2026-02-04