M41T56 Datasheet, PDF (1/28 Pages) STMicroelectronics – 512 bit 64b x8 Serial Access TIMEKEEPER SRAM

M41T56
Serial Real Time Clock with 56 bytes NVRAM
Feature summary
■ Counters for seconds, minutes, hours, day,
date, month, years, and century
■ 32 KHz crystal oscillator integrating load
capacitance (12.5pF) providing exceptional
oscillator stability and high crystal series
resistance operation
■ Serial interface supports I²C Bus (400kHz
protocol)
■ Ultra-low battery supply current of 450nA
(typ@3V)
■ 5V ±10% supply voltage
■ Timekeeping down to 2.5V
■ Automatic power-fail detect and switch circuitry
■ 56 bytes of general purpose RAM
■ Software clock calibration to compensate
crystal deviation due to temperature
■ Automatic leap year compensation
■ Operating temperature of –40 to 85°C
■ Packaging options include:
– 28-lead SOIC and SNAPHAT^® TOP (to be
ordered separately)
– SO8N
8
1
SO8N (M) 150mil width
SNAPHAT (SH) battery & crystal
28
1
SOH28 (MH)
October 2006
Rev 5
1/28
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