Description
●The M41T6x serial access TIMEKEEPER® is a low power serial RTC with a built-in 32.768 kHz oscillator. 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, 32 KHz output, calibration, and watchdog 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
●■ Serial RTC with alarm functions
●– 400 kHz I2C serial interface
●– Memory mapped registers for seconds, minutes, hours, day, date, month, year, and century
●– Tenths/hundredths of seconds register
●■ 350 nA timekeeping current at 3 V
●■ Timekeeping down to 1.0 V
●■ 1.3 V to 4.4 V I2C bus operating voltage
●– 4.4 V max VCCsuitable for lithium-ion battery operation
●■ Low operating current of 35 µA (at 400 kHz)
●■ 32 KHz square wave output is on at power-up.
● Suitable for driving a microcontroller in lowpower mode. Can be disabled. (M41T62/63/64)
●■ Programmable 1 Hz to 32 KHz square wave output (M41T62/63/64)
●■ Programmable alarm with interrupt function (M41T62/65)
●■ 32 KHz crystal oscillator integrates crystal load capacitors, works with high series resistance crystals
●■ Oscillator stop detection monitors clock operation
●■ Accurate programmable watchdog
●– 62.5 ms to 31 min timeout
●■ Software clock calibration. Can adjus timekeeping to within ±2 parts per million (±5 seconds per month)
●■ Automatic leap year compensation
●■ –40 to +85 °C operation
●■ Very small 3 mm x 3 mm, Lead-free 16-lead QFN
