DS1251/DS1251P

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BATTERY LONGEVITY

The DS1251 has a lithium power source that is designed to provide energy for clock activity, and clock

is sufficient to power the DS1251 continuously for the life of the equipment in which it is installed. For

specification purposes, the life expectancy is 10 years at +25

°C with the internal clock oscillator running

present.

CLOCK ACCURACY (DIP MODULE)

The DS1251 is guaranteed to keep time accuracy to within

±1 minute per month at +25°C. The clock is

calibrated at the factory by Dallas Semiconductor using special calibration nonvolatile tuning elements.

The DS1251 does not require additional calibration and temperature deviations will have a negligible

effect in most applications. For this reason, methods of field clock calibration are not available and not

necessary.

CLOCK ACCURACY (POWERCAP MODULE)

The DS1251P and DS9034PCX are each individually tested for accuracy. Once mounted together, the

module is guaranteed to keep time accuracy to within

±1.53 minutes per month (35ppm) at +25°C.