M48T02 Datasheet, PDF (1/15 Pages) STMicroelectronics – 16 Kbit 2Kb x8 TIMEKEEPER[ SRAM

M48T02
M48T12
16 Kbit (2Kb x8) TIMEKEEPER^® SRAM
INTEGRATED ULTRA LOW POWER SRAM,
REAL TIME CLOCK and POWER-FAIL
CONTROL CIRCUIT
BYTEWIDE™ RAM-LIKE CLOCK ACCESS
BCD CODED YEAR, MONTH, DAY, DATE,
HOURS, MINUTES and SECONDS
TYPICAL CLOCK ACCURACY of ± 1 MINUTE
a MONTH, AT 25°C
SOFTWARE CONTROLLED CLOCK
CALIBRATION for HIGH ACCURACY
APPLICATIONS
AUTOMATICPOWER-FAILCHIP DESELECTand
WRITE PROTECTION
WRITE PROTECT VOLTAGES
(V_PFD = Power-fail Deselect Voltage):
– M48T02: 4.5V ≤ V_PFD ≤ 4.75V
– M48T12: 4.2V ≤ VPFD ≤ 4.5V
SELF-CONTAINED BATTERY and CRYSTAL
in the CAPHAT DIP PACKAGE
PIN and FUNCTION COMPATIBLE with
JEDEC STANDARD 2Kb x8 SRAMs
24
1
PCDIP24 (PC)
Battery/Crystal CAPHAT
Figure 1. Logic Diagram
DESCRIPTION
The M48T02/12 TIMEKEEPER^® RAM is a 2Kb x8
non-volatile static RAM and real time clock which
is pin and functional compatible with the DS1642.
A special 24 pin 600mil DIP CAPHAT™ package
houses the M48T02/12 silicon with a quartz crystal
and a long life lithium button cell to form a highly
integratedbatterybacked-upmemoryand real time
clock solution.
Table 1. Signal Names
A0-A10
Address Inputs
DQ0-DQ7 Data Inputs / Outputs
E
Chip Enable
G
Output Enable
W
Write Enable
V_CC
Supply Voltage
V_SS
Ground
VCC
11
A0-A10
8
DQ0-DQ7
W
M48T02
M48T12
E
G
VSS
AI01027
November 1998
1/15