M41T81S_12 Datasheet, PDF (1/32 Pages) STMicroelectronics – Serial access real-time clock (RTC) with alarms

M41T81S
Serial access real-time clock (RTC) with alarms
Features
■ Counters for tenths/hundredths of seconds,
seconds, minutes, hours, day, date, month,
year, and century
■ 32 KHz crystal oscillator with integrated load
capacitance (12.5 pf) which provides
exceptional oscillator stability and high crystal
series resistance operation)
■ Oscillator stop detection (monitors clock
operation)
■ Serial interface supports I²C bus (400 kHz
protocol)
■ Ultra-low battery supply current of 0.6 µA (typ)
■ 2.0 to 5.5 V clock operating voltage
■ Automatic switchover and deselect circuitry
(fixed reference) which provides full operation
in 3.0 V applications)
■ V_CC = 2.7 to 5.5 V
■ 2.5 V ≤ V_PFD ≤ 2.7 V
■ Power-down time-stamp (HT bit) which allows
determination of time elapsed in battery
backup
■ Battery low flag
■ 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 for
crystal deviation due to temperature)
■ Operating temperature of –40 to 85 °C
■ Package options include an 8-lead SOIC or
18-lead embedded crystal SOIC
Datasheet − production data
8
1
SO8
8-pin SOIC
18
1
SOX18
18-pin (300 mil) SOIC
with embedded crystal
May 2012
This is information on a product in full production.
Doc ID 10773 Rev 7
1/32
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