TRD to Digital Converter, 4.5V to 5.5V, DIP 24 - 

The DS12887+ is a real time clock in 24 pin DIP package. This device provides real time clock/calendar, one time of day alarm, three maskable interrupts with common interrupt output, programmable square wave and 114bytes of battery backed static RAM. The DS12887 integrates quartz crystal and lithium energy source into 24 pin encapsulated DIP package. The date at end of the month is automatically adjusted for months with fewer than 31 days including correction for leap years. The devices also operate in either 24hour or 12hour format with an AM/PM indicator. A precision temperature compensated circuit monitors the status of VCC. If primary power failure is detected, the device automatically switches to backup supply. It is accessed through multiplexed byte wide interface which supports both Intel and Motorola modes.