M41T81 Datasheet PDF - STMicroelectronics

SUMMARY DESCRIPTION
The M41T81 Serial Access TIMEKEEPER® SRAM is a low power Serial RTC with a built-in 32.768 KHz oscillator (external crystal controlled).
   
FEATURES SUMMARY
■ 2.0 TO 5.5V CLOCK OPERATING VOLTAGE
■ COUNTERS FOR TENTHS/HUNDREDTHS
    OF SECONDS, SECONDS, MINUTES,
    HOURS, DAY, DATE, MONTH, YEAR, and
    CENTURY
■ AUTOMATIC SWITCH-OVER and DESELECT
    CIRCUITRY
■ SERIAL INTERFACE SUPPORTS I2C BUS
    (400KHz PROTOCOL)
■ PROGRAMMABLE ALARM and INTERRUPT
    FUNCTION (valid even during Battery Back-up
    Mode)
■ WATCHDOG TIMER
■ LOW OPERATING CURRENT OF 400µA
■ BATTERY BACK-UP NOT RECOMMENDED
    FOR 3.0V APPLICATIONS (CAPACITOR
    BACK-UP ONLY)
■ BATTERY OR SUPER-CAP BACK-UP
■ OPERATING TEMPERATURE OF –40 TO
    85°C
■ ULTRA-LOW BATTERY SUPPLY CURRENT
    OF 1µA
■ PACKAGE OPTIONS INCLUDE A 28-LEAD or
    18-LEAD EMBEDDED CRYSTAL SOIC