Cypress STK22C48 Manual De Usuario

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STK22C48
16 Kbit (2K x 8) AutoStore nvSRAM
Cypress Semiconductor Corporation
198 Champion Court
San Jose
,
CA 95134-1709
408-943-2600
Document Number: 001-51000 Rev. **
 Revised January 30, 2009
Features
25 ns and 45 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 
Commercial and industrial temperatures
28-pin 300 mil and (330 mil) SOIC package
RoHS compliance
Functional Description
The Cypress STK22C48 is a fast static RAM with a nonvolatile
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. A hardware STORE is initiated with
the HSB pin.
  
STORE/
RECALL
CONTROL
POWER
CONTROL
STATIC RAM
ARRAY
32 X 512
Quantum Trap
32 X 512
STORE
RECALL
COLUMN I/O
COLUMN DEC
ROW DECODER
INPUT
 BUFFERS
OE
CE
WE
HSB
V
CC
V
CAP
A
0
A
1
A
2
A
3
A
4
A
10
A
5
A
6
A
7
A
8
A
9
DQ
0
DQ
1
DQ
2
DQ
3
DQ
4
DQ
5
DQ
6
DQ
7
Logic Block Diagram