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STK12C68-M Datasheet, PDF (1/10 Pages) List of Unclassifed Manufacturers – CMOS NV SRAM 8K X 8 AUTOSTORE NONVOLATILE STATIC RAM
STK12C68-M
FEATURES
STK12C68-M
CMOS nvSRAM
8K x 8 AutoStore™
Nonvolatile Static RAM
MIL-STD-883 / SMD # 5962-94599
DESCRIPTION
• 40, 45 and 55ns Access Times
• 15 mA ICC at 200ns Access Speed
• Automatic STORE to EEPROM on Power Down
• Hardware or Software initiated STORE to
EEPROM
• Automatic STORE Timing
• 100,000 STORE cycles to EEPROM
• 10 year data retention in EEPROM
• Automatic RECALL on Power Up
• Software initiated RECALL from EEPROM
• Unlimited RECALL cycles from EEPROM
• Single 5V±10% Operation
• Available in multiple standard packages
The Simtek STK12C68-M is a fast static RAM (40, 45
and 55ns), with a nonvolatile EEPROM element incor-
porated in each static memory cell. The SRAM can be
read and written an unlimited number of times, while
independent nonvolatile data resides in EEPROM.
Data transfers from the SRAM to the EEPROM (the
STORE operation) take place automatically upon power
down using charge stored in an external 100 µF
capacitor. Transfers from the EEPROM to the SRAM
(the RECALL operation) take place automatically on
power up. Software sequences may also be used to
initiate both STORE and RECALL operations. A
STORE can also be initiated via a single pin.
The STK12C68-M is available in the following pack-
ages: a 28-pin 300 mil ceramic DIP and 28-pad LCC.
LOGIC BLOCK DIAGRAM
A3
A4
A
5
A6
A7
A8
A9
A12
DQ0
DQ1
DQ2
DQ3
DQ4
DQ5
DQ6
DQ7
EEPROM ARRAY
256 x 256
STATIC RAM
ARRAY
256 x 256
STORE
RECALL
COLUMN I/O
COLUMN DECODER
A 0 A 1 A 2 A10 A11
A 0 A 12
STORE/
RECALL
CONTROL
4-53
PIN CONFIGURATIONS
HSB
A6
A5
A4
A3
A2
A1
A0
DQ0
DQ1
32
28 27
4
1
26
5
25
6
24
7
23
8 TOP VIEW 22
9
21
10
20
11
19
12
18
13 14 15 16 17
HSB
A8
A9
A11
G
A10
E
DQ7
DQ 6
VCAP 1
A 12 2
A7 3
A6 4
A5 5
A4 6
A3 7
A2 8
A1 9
A 0 10
DQ 0 11
DQ 1 12
DQ 2 13
VSS 14
28 VCCX
27 W
26 HSB
25 A 8
24 A 9
23 A 11
22 G
21 A 10
20 E
19 DQ 7
18 DQ 6
17 DQ 5
16 DQ 4
15 DQ 3
28 - LCC
28 - 300 C-DIP
PIN NAMES
A0 - A12
Address Inputs
W
Write Enable
DQ0 - DQ7 Data In/Out
E
Chip Enable
G
G
Output Enable
VCCX
Power (+5V)
VSS
Ground
E
VCAP
Capacitor
W
HSB
Hardware Store/Busy
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