M41T00S

Description

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Description

in 32.768 kHz oscillator (external crystal controlled). Eight bytes of the SRAM (see Table 2

on page 13) 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,

each WRITE or READ data byte.

The M41T00S has a built-in power sense circuit which detects power failures and

automatically switches to the battery supply when a power failure occurs. The energy

needed to sustain the clock operations can be supplied by a small lithium button supply

when a power failure occurs. The eight clock address locations contain the century, year,

month, date, day, hour, minute, and second in 24-hour BCD format. Corrections for 28, 29

(leap year - valid until year 2100), 30 and 31 day months are made automatically.

The M41T00S is supplied in an 8-pin SOIC.

Figure 1.

Logic diagram

Table 1.

Signal names

XI

Oscillator input

XO

Oscillator output

FT/OUT

Frequency test / output driver (open drain)

SDA

Serial data input/output

SCL

Serial clock input

Battery supply voltage

Supply voltage

Ground

SCL

VCC

M41T00S

VSS

SDA

FT/OUT

VBAT

XI

XO

AI09165