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FEATURES
Accepts standard 32K x 8 or 128K x 8
CMOS static RAMs
Embedded lithium energy cell retains RAM
data
Self-contained circuitry safeguards data
Data retention time is greater than 10 years
with the proper RAM selection
IC socket permits upgrading from 32K x 8 to
128K x 8 RAM
Proven gas-tight socket contacts
Operating temperature range 0°C to 70°C
PIN ASSIGNMENT
PIN DESCRIPTION
CE - Conditioned Chip Enable
V
CC
- Switched V
CC
GND - Ground
All pins pass through except 22, 30 and 32.
DESCRIPTION
The DS1213D SmartSocket is a 32-pin, 600 mil DIP socket with a built-in CMOS controller circuit and
an embedded lithium energy source. It accepts 32K x 8 or 128K x 8 JEDEC bytewide CMOS static
RAM. When the socket is mated with a CMOS RAM, it provides a complete solution to problems
associated with memory volatility. The SmartSocket monitors incoming V
CC
for an out-of-tolerance
condition. When such a condition occurs, an internal lithium energy source is automatically switched on
and write protection is unconditionally enabled to prevent data corruption. Using the SmartSocket saves
printed circuit board space since the SRAM/SmartSocket combination occupies no more area than the
SRAM alone. The SmartSocket uses only Pins 22, 30 and 32 for RAM control. All other pins are passed
straight through.
See the DS1213B SmartSocket data sheet for technical details.
See Dallas Semiconductor Application Note 4 for modification instructions to allow use of 512K x8
RAM with this part.
DS1213D
SmartSocket 256k/1M
www.dalsemi.com
30 V
CC
32-Pin Intelligent Socket
3
1
9
8
5
10
12
11
13
32 V
CC
31
26
24
25
29
28
23
21
22 CE
20
19
14
15
16
18
17
GND
