The DS12C887+ is a real time clock (RTC) in 24 pin EDIP package. This RTC is designed to be direct replacements for the DS1285. The device provide a real time clock/calendar, one time of day alarm, three maskable interrupts with a common interrupt output, a programmable square wave and 113 bytes of battery backed static RAM. It adds a century byte at address 32h, the date at the end of the month is automatically adjusted for months with fewer than 31 days, including correction for leap years. The device also operate in either 24-hour or 12-hour format with an AM/PM indicator. A precision temperature-compensated circuit monitors the status of VCC. If a primary power failure is detected device automatically switches to a backup supply. It is used in embedded systems, utility meters and network hubs, bridges and routers.
Supply voltage range is 4.5V to 5.5V
Operating temperature range from 0°C to 70°C & periodic rates from 122µs to 500ms
Drop-in replacement for IBM AT computer clock/calendar, 14 bytes of clock and control registers
Counts seconds, minutes, hours, day, date, month and year with leap year compensation through 2099
Binary or BCD time representation, daylight saving time option & end of clock update cycle flag
Selectable intel or motorola bus timing, interfaced with software as 128 RAM locations
Time of day alarm once per second to once per day, RAM clear function
