VCC

Port

Reset Input

SQWIN

Serial Clock Line

Serial Data Line

32KHz CLKIN

XO

XI

M41T6x

MCU

VSS

IRQ/FT/OUT

(2)

WDO

(3)

SQW

(4)

F32K

SDA

SCL

VCC

VCC

(1)

D1

D2

POWER SUPPLY

+

–

LEAKAGE

PATH

Ro

1.

Diode D2 is required on open drain pin (M41T65 only) when SuperCap (or battery) backup is being used.

Low threshold BAT42 Schottky diode is recommended (see note below). D1 and D2 should be of the same

type.

2.

For M41T62 and M41T65 (open drain).

3.

For M41T65 (open drain).

4.

For M41T64 (open drain).

Note:

Some power supplies, when shut off, can present a leakage path to ground, which shortens the backup time

provided by the SuperCap (or battery). In such cases, a very low leakage diode is recommended for D1 (and

D2).

M41T62, M41T64, M41T65

Description

DS3840 - Rev 24

page 6/42