RTC with integrated NVSRAM — what the 114B buys you
The DS12887A+ is a parallel-interface real-time clock (RTC) that also packs 114 bytes of non-volatile SRAM (NVSRAM) on-chip. That NVSRAM holds configuration data, calibration constants, or event logs through a power loss — no external EEPROM needed for small persistent stores. It tracks time in HH:MM:SS (12/24 hr) and date in YY-MM-DD-dd format, with built-in alarm, daylight-savings adjustment, leap-year correction, and a square-wave output for driving a periodic interrupt.
Supply rails and battery-backup design
The RTC automatically switches to the battery when Vcc drops below Vbatt — no external diode ORing needed. Timekeeping current maxes at 15 mA across the full supply range.
Through-hole 24-EDIP — board-fit reality
Housed in a 24-pin DIP module with 0.600-inch (15.24 mm) row spacing, the DS12887A+ uses the 24-EDIP supplier package. The through-hole footprint is large by modern standards — it takes up about 30 mm × 15 mm of board area — but it's hand-solderable and easy to rework. The module contains the crystal and battery internally, so no external timing components or coin-cell holder are needed on the PCB. That simplifies layout but also means the entire module must be replaced if the battery depletes.
Active production — sourcing posture
Analog Devices lists the DS12887A+ as Active. It is RoHS3 compliant.