STK20C04
512 x 8 nvSRAM
QuantumTrap™
CMOS
Nonvolatile Static RAM
Obsolete - Not Recommend for new Designs
FEATURES
• 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 I
CC
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
DESCRIPTION
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
RAM
s in a 28-pin 600 mil plastic
DIP
.
BLOCK DIAGRAM
Quantum Trap
16 x 256
ROW DECODER
STORE
STATIC RAM
ARRAY
16 x 256
RECALL
PIN CONFIGURATIONS
NE
NC
A
7
A
6
A
5
A
4
A
3
A
2
A
1
A
0
DQ
0
DQ
1
DQ
2
V
SS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
28
27
26
25
24
23
22
21
20
19
18
17
16
15
A
5
A
6
A
7
A
8
V
CC
W
NC
A
8
NC
NC
G
NC
E
DQ
7
DQ
6
DQ
5
DQ
4
DQ
3
28 - 600 PDIP
DQ
0
DQ
1
DQ
2
DQ
3
DQ
4
DQ
5
DQ
6
DQ
7
INPUT BUFFERS
COLUMN I/O
COLUMN DEC
PIN NAMES
STORE/
RECALL
CONTROL
A
0
- A
8
W
DQ
0
- DQ
7
Address Inputs
Write Enable
Data In/Out
Chip Enable
Output Enable
Nonvolatile Enable
Power (+ 5V)
Ground
A
0
A
1
A
2
A
3
A
4
E
G
NE
E
W
G
NE
V
CC
V
SS
March 2006
1
Document Control # ML0001 rev 0.2
SIMTEK [ SIMTEK CORPORATION ]
