The M41T01 is a low-power serial real-time clock (RTC). The built-in 32.768 kHz oscillator circuit works with an external crystal and does not need any load capacitors.
The M41T01 clock has a built-in power sense circuit which detects power failures and automatically switches to the battery supply during power failures. 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. The energy needed to sustain the RAM and clock operations can be supplied from a small lithium coin cell.
Typical data retention time is in excess of 5 years with a 50 mA/h 3 V lithium cell. The M41T01 is supplied in an 8-lead plastic small outline package.
- 2.0 to 5.5 V clock operating voltage
- Counters for seconds, minutes, hours, day, date, month, years, and century
- Software clock calibration
- Automatic switchover and deselect circuitry
- Ultra-low battery supply current of 800 nA
- Low operating current of 300 μA
- Battery and capacitor backup
- Battery backup not recommended for 3.0 V applications (capacitor backup only)
- Operating temperature of –40 to 85 °C
- Automatic leap year compensation
RoHS Compliance Grade
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