M41T66_11 datasheet(5/34 Pages) STMICROELECTRONICS

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M41T66

Description

Doc ID 15108 Rev 2

5/34

Description

The M41T66 is a low-power serial real-time clock (RTC) with a built-in 32.768 kHz oscillator

(external crystal controlled). Eight registers are used for the clock/calendar function and are

configured in binary coded decimal (BCD) format. An additional 8 registers provide

status/control of alarm, square wave, calibration, and watchdog functions. Addresses and

data are transferred serially via a two line, bidirectional I2C interface. The built-in address

Functions available to the user include a time-of-day clock/calendar, alarm interrupts,

programmable square wave output, and watchdog output. The eight clock address locations

contain the century, year, month, date, day, hour, minute, second and tenths/hundredths of a

second in 24-hour BCD format. Corrections for 28-, 29- (leap year), 30- and 31-day months

are made automatically.

The M41T66 is supplied in a 16-pin QFN.

Figure 1.

M41T66 logic diagram

Open drain

Defaults to 32 KHz on power-up

M41T66 Datasheet(PDF) 5 Page - STMicroelectronics