STK20C04
512 x 8 nvSRAM
QuantumTrap™ CMOS
Nonvolatile Static RAM
Obsolete - Not Recommend for new Designs
FEATURES
DESCRIPTION
• 25ns, 35ns and 45ns Access Times
• STORE to Nonvolatile Elements Initiated by
Hardware
• RECALL to SRAM Initiated by Hardware or
Power Restore
• Automatic STORE Timing
• 10mA Typical ICC at 200ns Cycle Time
• Unlimited READ, WRITE and RECALL Cycles
• 1,000,000 STORE Cycles to Nonvolatile Ele-
ments
• 100-Year Data Retention over Full Industrial
Temperature Range
• Commercial and Industrial Temperatures
The Simtek STK20C04 is a fast static RAM with a non-
volatile element incorporated in each static memory
cell. The SRAM can be read and written an unlimited
number of times, while independent nonvolatile data
resides in nonvolatile elements. Data may easily be
transferred from the SRAM to the Nonvolatile Elements
(the STORE operation), or from the Nonvolatile Ele-
ments to the SRAM (the RECALL operation), using the
NE pin. Transfers from the Nonvolatile Elements to the
SRAM (the RECALL operation) also take place auto-
matically on restoration of power. The STK20C04
combines the high performance and ease of use of a
fast SRAM with nonvolatile data integrity.
The STK20C04 features industry-standard pinout for
nonvolatile RAMs in a 28-pin 600 mil plastic DIP.
PIN CONFIGURATIONS
BLOCK DIAGRAM
1
NE
28
27
26
25
24
23
22
21
20
19
18
17
16
15
V
CC
W
NC
2
Quantum Trap
16 x 256
NC
3
A
A
A
A
A
7
4
A
6
5
4
3
2
8
5
NC
NC
G
NC
E
6
STORE
7
A
A
A
A
5
6
7
8
8
A
9
A
STATIC RAM
ARRAY
1
0
RECALL
10
11
12
13
14
A
DQ
DQ
7
6
5
DQ
0
16 x 256
DQ
DQ
1
2
DQ
DQ
DQ
4
3
V
SS
28 - 600 PDIP
PIN NAMES
DQ0
DQ1
DQ2
DQ3
DQ4
COLUMN I/O
STORE/
RECALL
CONTROL
A
- A
Address Inputs
Write Enable
Data In/Out
0
8
COLUMN DEC
W
DQ - DQ
0
7
E
Chip Enable
Output Enable
Nonvolatile Enable
Power (+ 5V)
Ground
DQ5
DQ6
DQ7
A3 A4
A0 A1 A2
G
NE
G
NE
E
V
V
CC
W
SS
March 2006
1
Document Control # ML0001 rev 0.2
SIMTEK [ SIMTEK CORPORATION ]
