This document describes the features and characteristics of a serial real-time clock (RTC) product called M41T11. The product includes counters for seconds, minutes, hours, day, date, month, years, and century, a 32KHz crystal oscillator, support for I2C bus, and ultra-low battery supply current.
The M41T11 is a low-power serial real-time clock (RTC) with 56 bytes of non-volatile RAM (NVRAM). It features a built-in 32.768 kHz oscillator controlled by an external crystal and supports the I2C bus protocol. The device includes automatic switchover to a backup battery during power failures to maintain timekeeping and data retention.
| Supply voltage | 2.0 to 5.5 V |
|---|---|
| Battery supply current | 0.8 µA (typ.) |
| Operating temperature | -40 to 85°C |
| NVRAM size | 56 bytes |
| Oscillator frequency | 32.768 kHz |
| Interface | I2C bus (100 kHz) |
The typical battery supply current is 0.8 µA at 3 V.
Yes, the M41T11 includes automatic leap year compensation.
The typical data retention time is in excess of 5 years.