DS1244

Voltage Range on Any Pin Relative to Ground                    -0.3V to +6.0V
Storage Temperature Range                                            -40ºC to +85ºC
Soldering Temperature Range               See IPC/JEDEC J-STD-020A (DIP)
                                                                                                  (Note 13)
13) RTC modules can be successfully processed through conventional wave-soldering techniques as long as temperature exposure to the lithium energy source contained within does not exceed +85°C. Postsolder cleaning with water-washing techniques is acceptable, provided that ultrasonic vibration is not
used.

The DS1244 256k NV SRAM with a Phantom clock is a fully static nonvolatile RAM (NV SRAM) (organized as 32k words by 8 bits) with a built-in real-time clock. The DS1244 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 DS1244 provides timekeeping information for hundredths of seconds, seconds, minutes, hours, days, date, 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.