Description

The M41T80 is a low power serial RTC with a built-in 32.768 kHz oscillator (external crystal controlled). Eight registers (see Table 3: Clock register map on page 14) are used for the clock/calendar function and are configured in binary coded decimal (BCD) format. An additional 12 registers provide status/control of alarm, 32 KHz output, and square wave functions. Addresses and data are transferred serially via a two line, bi-directional I2C interface. The built-in address register is incremented automatically after each WRITE or READ data byte.

Features

■ 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)

■ 2.0 to 5.5 V clock operating voltage

■ 32 KHz square wave on power-up to drive a

microcontroller in low-power mode

■ Programmable (1 Hz to 32 KHz) square wave

■ Programmable alarm and interrupt function

■ Low operating current of 200 µA

■ Operating temperature of –40 to 85 °C

■ ECOPACK® package available