DS1244Y-70+

The DS1244Y-70+ is a 256K NV SRAM with Phantom clock in 28 pin EDIP package. The 256K NV SRAM with a Phantom clock is a fully static non-volatile 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, 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 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.

• Supply voltage range is 4.5V to 5.5V
• Operating temperature range from 0°C to 70°C
• 32K x 8 NV SRAM directly replaces volatile static RAM or EEPROM
• Read cycle time and access time is 70ns
• Embedded lithium energy cell maintains calendar operation and retains RAM data
• Watch function is transparent to RAM operation
• Automatic leap year compensation valid up to 2100
• Over 10 years of data retention in the absence of power
• Lithium energy source is disconnected to retain freshness until power is applied for the first time
• UL recognized

Applications

Clock & Timing

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party