DS1251P

Voltage Range on Any Pin Relative to Ground        -0.3V to +6.0V
Soldering Temperature Range                               +260°C for 10 seconds (DIP) (Note 13) See IPC/JEDEC Standard J-STD-020A for Surface Mount Devices

The DS1251 4096k NV SRAM with Phantom Clock is a fully static nonvolatile RAM (organized as 512k words by 8 bits) with a built-in real-time clock. The DS1251Y has a self-contained lithium energy source and control circuitry, which constantly monitors VCC  for an out-of-tolerance  condition. When such a condition occurs, the lithium energy source is automatically switched on and write protection is unconditionally enabled to prevent garbled data in both the memory and real-time clock.

The phantom clock DS1251 provides timekeeping information including hundredths of seconds, seconds, minutes, hours, days, dates, months, and years. The date at  the end of the month is automatically adjusted for months with fewer than 31 days, including correction for leap years. The phantom clock operates in either 24-hour or 12-hour format with an AM/PM indicator.