
STMicroelectronics
Description
The M41T00 is a low power serial real-time clock with a built-in 32.768 kHz oscillator (external crystal controlled). Eight bytes of the RAM are used for the clock/calendar function and are configured in binary-coded decimal (BCD) format. Addresses and data are transferred serially via a two-line bidirectional bus. The built-in address register is incremented automatically after each WRITE or READ data byte.
FEATUREs
• For new designs use M41T00S
• Counters for seconds, minutes, hours, day, month, years, 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 (100 kHz protocol)
• Ultra low battery supply current of 0.8 μA (typ at 3 V)
• 2.0 to 5.5 V clock operating voltage
• Automatic switchover and deselect circuitry (for 3 V application select M41T00S datasheet)
• Software clock calibration to compensate crystal deviation due to temperature
• Automatic leap year compensation
• Operating temperature of -40 to 85 °C