m41t00s STMicroelectronics, m41t00s Datasheet - Page 4

• Manufacturer Part Number: m41t00s
• Description: Serial Access Real-time Clock
• Manufacturer: STMicroelectronics

M41T00S
SUMMARY DESCRIPTION
The M41T00S Serial Access TIMEKEEPER
SRAM is a low power Serial RTC with a built-in
32.768kHz oscillator (external crystal controlled).
Eight bytes of the SRAM (see
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, bi-directional I
address register is incremented automatically af-
ter each WRITE or READ data byte.
The M41T00S has a built-in power sense circuit
which detects power failures and automatically
Figure 2. Logic Diagram
Note: 1. For SO8 package only.
4/23
XO
XI
SDA
SCL
(1)
(1)
V CC
M41T00S
V SS
V BAT
2
C interface. The built-in
Table 2., page
FT/OUT
AI09165
11)
®
switches to the battery supply when a power fail-
ure 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.
Table 1. Signal Names
Note: 1. For SO8 package only.
Figure 3. 8-pin SOIC (M) Connections
Note: 1. Open Drain Output
FT/OUT
XO
V
XI
SDA
SCL
V
V
BAT
CC
SS
(1)
(1)
V
V
XO
BAT
SS
XI
Oscillator Input
Oscillator Output
Frequency Test / Output Driver
(Open Drain)
Serial Data Input/Output
Serial Clock Input
Battery Supply Voltage
Supply Voltage
Ground
1
2
3
4
M41T00S
5
8
7
6
V
FT/OUT
SCL
SDA
CC
AI09166
(1)