M41T81M6E屬于集成電路（IC）的實時時鐘。由意法半導(dǎo)體集團制造生產(chǎn)的M41T81M6E實時時鐘實時時鐘 (RTC) 為幾乎所有需要保持精確時間的電子設(shè)備提供時間和/或日期信息。時鐘類型有二進制計數(shù)器、時鐘/日歷/監(jiān)控器、歷時計時器、幻時鐘芯片、便攜式系統(tǒng)控制器、溫度記錄器、時間事件記錄器和計時器時鐘外設(shè)。其包含 2 B 至 2 MB 不等的存儲器，接口選項有 I2C、并行、串行、SPI、1 線式、2 線式、3 線式和 4 線式。

描述 Description

The M41T81 is a low-power serial RTC with a built-in 32.768 kHz oscillator (external crystal controlled).

特性 Features

■ For all new designs other than automotive, use

M41T81S (contact the ST sales office for

automotive grade)

■ 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

protocol)

■ Ultra-low battery supply current of 0.6 μA

(typ at 3 V)

■ 2.0 to 5.5 V clock operating voltage

■ Automatic switch-over and deselect circuitry

(for 3 V application select M41T81S datasheet)

■ Power-down time stamp (HT bit) allowing

determination of time elapsed in battery

backup

■ Programmable alarm and interrupt function

(valid even during battery backup mode)

■ Accurate programmable watchdog timer (from

62.5 ms to 128 s)

■ Software clock calibration to compensate

crystal deviation due to temperature

■ Operating temperature of –40 to 85 °C

■ ECOPACK? package available