M41T81_08 Datasheet, PDF (1/30 Pages) STMicroelectronics – Serial access real-time clock with alarm

M41T81
Serial access real-time clock with alarm
Not For New Design
Features
■ For new designs use M41T81S
■ Counters for tenths/hundredths of seconds,
seconds, minutes, hours, day, date, month,
year, and century
■ 32 KHz crystal oscillator integrating load
capacitance (12.5 pF) providing exceptional
oscillator stability and high crystal series
resistance operation
■ Serial interface supports I²C bus (400 kHz
protocol)
■ Ultra-low battery supply current of 0.6 µA
(typ at 3 V)
■ 2.0 to 5.5 V clock operating voltage
■ Automatic switch-over and deselect circuitry
(for 3V application select M41T81S datasheet)
■ Power-down time stamp (HT bit) allowing
determination of time elapsed in battery
backup
■ Programmable alarm and interrupt function
(valid even during battery backup mode)
■ Accurate programmable watchdog timer (from
62.5 ms to 128 s)
■ Software clock calibration to compensate
crystal deviation due to temperature
■ Operating temperature of –40 to 85°C
■ ECOPACK^® package available
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SO8 (M)
8-pin SOIC
May 2008
Rev 9
This is information on a product still in production but not recommended for new designs.
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