The M41T0 is one of our lowest-cost Serial
Real-Time Clocks and is ideally suited to applications needing a
simple Real-Time Clock with short back-up duration or no back-up.
Serial RTC 400kHz I2C Bus
BCD Registers for Hours, Minutes, Seconds, Year, Month,
Day, and Date
Century Bit
2.0 to 5.5V Operation - 900nA Standby Current (@3.0V)