STK14C88
32K x 8 AutoStore™ nvSRAM
QuantumTrap™ CMOS
Nonvolatile Static RAM
FEATURES
DESCRIPTION
• 20ns, 25ns, 35ns and 45ns Access Times
The Simtek STK14C88 is a fast static RAM with a
• “Hands-off” Automatic STORE with External
68µF Capacitor on Power Down
nonvolatile, electrically erasable PROM 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
EEPROM. Data transfers from the SRAM to the
EEPROM (the STORE operation) can take place
automatically on power down. A 68µF or larger
capacitor tied from VCAP to ground guarantees the
STORE operation, regardless of power-down slew
rate or loss of power from “hot swapping”. Transfers
from the EEPROM to the SRAM (the RECALL opera-
tion) take place automatically on restoration of
power. Initiation of STORE and RECALL cycles can
also be software controlled by entering specific read
sequences. A hardware STORE may be initiated with
the HSB pin.
• STORE to EEPROM Initiated by Hardware,
Software or AutoStore™ on Power Down
• RECALL to SRAM Initiated by Software or
Power Restore
• 10mA Typical ICC at 200ns Cycle Time
• Unlimited READ, WRITE and RECALL Cycles
• 1,000,000 STORE Cycles to EEPROM
• 100-Year Data Retention in EEPROM
• Single 5V + 10% Operation
• Not Sensitive to Power On/Off Ramp Rates
• No Data Loss from Undershoot
• Commercial and Industrial Temperatures
• 32-Pin SOIC and DIP Packages
BLOCK DIAGRAM
PIN CONFIGURATIONS
V
V
1
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
CCX
CAP
VCCX
VCAP
A
2
HSB
W
14
A
3
12
A
A
A
A
A
NC
A
2
A
A
4
A
7
6
5
4
3
13
EEPROM ARRAY
512 x 512
5
A
8
POWER
CONTROL
A
9
A
11
G
NC
6
A5
A6
A7
7
8
STORE
9
10
11
12
13
14
15
16
A
STORE/
RECALL
CONTROL
10
A8
STATIC RAM
E
1
HSB
RECALL
A9
ARRAY
DQ
0
7
6
5
512 x 512
A11
A12
A13
A14
DQ
DQ
DQ
DQ
DQ
0
1
2
32 - 300 SOIC
32 - 600 PDIP
DQ
DQ
4
3
V
SS
SOFTWARE
DETECT
A0 - A13
DQ0
DQ1
DQ2
PIN NAMES
COLUMN I/O
A - A
Address Inputs
COLUMN DEC
0
14
DQ -DQ
0
Data In/Out
DQ3
DQ4
7
E
Chip Enable
DQ5
DQ6
DQ7
W
Write Enable
Output Enable
Hardware Store Busy (I/O)
Power (+ 5V)
Capacitor
A0 A1 A2 A3 A4 A10
G
G
HSB
E
V
V
V
CCX
CAP
SS
W
Ground
July 1999
5-21
SIMTEK [ SIMTEK CORPORATION ]
