MICROCHIP MCP795W10-I/SL

The MCP795W10-I/SL is a low-power Real-Time Clock/Calendar (RTCC) uses digital trimming compensation for an accurate clock/calendar, an interrupt output to support alarms and events, a power sense circuit that automatically switches to the backup supply, non-volatile memory for safe data storage and several enhanced features that support system requirements. Along with a 32768kHz crystal, this RTCC tracks time using several internal registers and then communicates the data over a 5MHz SPI bus that is fast enough to support a programmable millisecond alarm. The device is fully accessible through the serial interface, while VCC is between 1.8 and 3.6V, but can operate down to 1.3V through the backup supply connected to the VBAT input for timekeeping and SRAM retention only. As part of the power sense circuit, a time saver function is implemented to store the time when main power is lost and again, when power is restored to log the duration of a power failure.