ANALOG DEVICES DS1554-70IND+

The DS1554-70IND+ is a 256K, Non-volatile, Y2K-compliant timekeeping RAM in 32 pin EDIP package. It has RTC alarm, watchdog timer, power-on reset, battery monitor and 32K x 8 non-volatile static RAM, user access to all registers within the DS1554 is accomplished with a byte wide interface. The RTC registers contain century, year, month, date, day, hours, minutes and seconds data in 24 hour binary coded decimal (BCD) format. Corrections for day of month and leap year are made automatically. The RTC registers are double buffered into an internal and external set. The user has direct access to external set. Clock/calendar updates to external set of registers can be disabled and enabled to allow user to access static data. Assuming internal oscillator is turned on, internal set of registers is continuously updated, this occurs regardless of external registers settings that accurate RTC information is always maintained.