Real-time clock, clock/calendar, SO-8

The DS1302 trickle-charge timekeeping chip contains a real-time clock/cale ndar and 31 bytes of static RAM. It communicates with a microprocessor via a simple serial inte rface. The real-time clock/ca lendar provides seconds, minutes, hours, day, date, month, and y ear information. The end of the mont h date is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in either the 24-hour or 12-hour format with an AM/PM indicator. Interfacing the DS1302 with a microprocessor is simplifi ed by using synchronous serial communication. Only three wires are required to communicate with the clock/RAM: CE, I/O (data line), and SCLK (serial clock). Data can be transferred to and from the clock/RAM 1 byte at a time or in a burst of up to 31 bytes. The DS1302 is designed to operate on very low power and retain data and clock information on less than 1 µ W.