M41T56M6E STMicroelectronics, M41T56M6E Datasheet - Page 4

• Manufacturer Part Number: M41T56M6E
• Description: IC SRAM SRL TIMEKPR 512BIT 8SOIC
• Manufacturer: STMicroelectronics
• Type: Clock/Calendar/NVSRAMr

Specifications of M41T56M6E

• Memory Size: 56B
• Time Format: HH:MM:SS (24 hr)
• Date Format: YY-MM-DD-dd
• Interface: I²C, 2-Wire Serial
• Voltage - Supply: 4.5 V ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 8-SOIC (3.9mm Width)
• Function: Clock/Calendar
• Rtc Memory Size: 64 Byte
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4.5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Rtc Bus Interface: Serial (2-Wire, I2C)
• Nvram Features: RTC, Internal Battery, XTAL
• Interface Type: I2C, Serial, 2-Wire
• Supply Voltage Range: 4.5V To 5.5V
• Memory Case Style: SOIC
• No. Of Pins: 8
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 497-2818-5; M41T56M6

M41T56
SUMMARY DESCRIPTION
The M41T56 TIMEKEEPER
bit static CMOS RAM organized as 64 words by 8
bits. A built-in 32,768Hz oscillator (external crystal
controlled) and the first 8 bytes of the RAM are
used for the clock/calendar function and are con-
figured in binary coded decimal (BCD) format. Ad-
dresses and data are transferred serially via a two-
line, bi-directional bus. The built-in address regis-
ter is incremented automatically after each WRITE
or READ data byte.
The M41T56 clock has a built-in power sense cir-
cuit which detects power failures and automatical-
ly switches to the battery supply during power
failures. The energy needed to sustain the RAM
and clock operations can be supplied from a small
lithium coin cell.
Typical data retention time is in excess of 10 years
with a 50mAh, 3V lithium cell. The M41T56 is sup-
plied in an 8-lead Plastic SOIC package or a 28-
lead SNAPHAT
Figure 3. Logic Diagram
4/24
OSCI
SCL
®
package.
V CC
V SS
M41T56
V BAT
®
is a low power, 512-
OSCO
SDA
FT/OUT
AI02304B
The 28-pin, 330mil SOIC provides sockets with
gold plated contacts at both ends for direct con-
nection to a separate SNAPHAT housing contain-
ing the battery and crystal. The unique design
allows the SNAPHAT battery package to be
mounted on top of the SOIC package after the
completion of the surface mount process. Inser-
tion of the SNAPHAT housing after reflow pre-
vents potential battery and crystal damage due to
the high temperatures required for device surface-
mounting. The SNAPHAT housing is keyed to pre-
vent reverse insertion. The SOIC and battery/crys-
tal packages are shipped separately in plastic anti-
static tubes or in Tape & Reel form.
For the 28-lead SOIC, the battery/crystal package
(e.g., SNAPHAT) part number is “M4Txx-
BR12SH” (see
Caution: Do not place the SNAPHAT battery/crys-
tal package “M4Txx-BR12SH” in conductive foam
as this will drain the lithium button-cell battery.
Table 1. Signal Names
OSCI
OCSO
FT/OUT
SDA
SCL
V
V
V
BAT
CC
SS
Table 16., page
Oscillator Input
Oscillator Output
Frequency Test / Output Driver
(Open Drain)
Serial Data Address Input / Output
Serial Clock
Battery Supply Voltage
Supply Voltage
Ground
22).