Cypress STK12C68-5 User Manual
64 kbit (8k x 8) autostore nvsram, Features, Functional description
STK12C68-5 (SMD5962-94599)
64 Kbit (8K x 8) AutoStore nvSRAM
Cypress Semiconductor Corporation
•
198 Champion Court
•
San Jose
,
CA 95134-1709
•
408-943-2600
Document Number: 001-51026 Rev. **
Revised March 02, 2009
Features
■
35 ns and 55 ns access times
■
Hands off automatic STORE on power down with external
68 µF capacitor
■
STORE to QuantumTrap™ nonvolatile elements is initiated
by software, hardware, or AutoStore™ on power down
■
RECALL to SRAM initiated by software or power up
■
Unlimited Read, Write, and Recall cycles
■
1,000,000 STORE cycles to QuantumTrap
■
100 year data retention to QuantumTrap
■
Single 5V+10% operation
■
Military temperature
■
28-pin (300mil) CDIP and 28-pad LCC packages
Functional Description
The Cypress STK12C68-5 is a fast static RAM with a nonvol-
atile element in each memory cell. The embedded nonvolatile
elements incorporate QuantumTrap technology producing the
world’s most reliable nonvolatile memory. The SRAM provides
unlimited read and write cycles, while independent nonvolatile
data resides in the highly reliable QuantumTrap cell. Data
transfers from the SRAM to the nonvolatile elements (the
STORE operation) takes place automatically at power down.
On power up, data is restored to the SRAM (the RECALL
operation) from the nonvolatile memory. Both the STORE and
RECALL operations are also available under software control.
A hardware STORE is initiated with the HSB pin.
Logic Block Diagram
STORE/
RECALL
CONTROL
POWER
CONTROL
SOFTWARE
DETECT
STATIC RAM
ARRAY
128 X 512
Quantum Trap
128 X 512
STORE
RECALL
COLUMN I/O
COLUMN DEC
ROW DECODER
INPUT
BUFFERS
OE
CE
WE
HSB
V
CC
V
CAP
A
0
-
A
12
A
0
A
1
A
2
A
3
A
4
A
10
A
5
A
6
A
7
A
8
A
9
A
11
A
12
DQ
0
DQ
1
DQ
2
DQ
3
DQ
4
DQ
5
DQ
6
DQ
7
Document Outline
- Features
- Functional Description
- Logic Block Diagram
- Pinouts
- Pin Definitions
- Device Operation
- SRAM Read
- SRAM Write
- AutoStore Operation
- AutoStore Inhibit Mode
- Hardware STORE (HSB) Operation
- Hardware RECALL (Power Up)
- Software STORE
- Software RECALL
- Data Protection
- Noise Considerations
- Hardware Protect
- Low Average Active Power
- Preventing Store
- Best Practices
- Maximum Ratings
- Operating Range
- DC Electrical Characteristics
- Data Retention and Endurance
- Capacitance
- Thermal Resistance
- AC Test Conditions
- AutoStore or Power Up RECALL
- Software Controlled STORE/RECALL Cycle
- Switching Waveform
- Part Numbering Nomenclature
- Ordering Information
- Sales, Solutions, and Legal Information