Rainbow Electronics AT25256A User Manual
Spi serial automotive eeproms, Features, Description
1
8-lead SOIC
1
2
3
4
8
7
6
5
CS
SO
WP
GND
VCC
HOLD
SCK
SI
Features
•
Serial Peripheral Interface (SPI) Compatible
•
Supports SPI Modes 0 (0,0) and 3 (1,1)
•
Medium-voltage and Standard-voltage Operation
– 5.0 (V
CC
= 4.5V to 5.5V)
– 2.7 (V
CC
= 2.7V to 5.5V)
•
3 MHz Clock Rate (5V)
•
64-byte Page Mode and Byte Write Operation
•
Block Write Protection
– Protect 1/4, 1/2, or Entire Array
•
Write Protect (WP) Pin and Write Disable Instructions for
both Hardware and Software Data Protection
•
Self-timed Write Cycle (5 ms Typical)
•
High-reliability
– Endurance: 100,000 Write Cycles
– Data Retention: >200 Years
•
8-lead PDIP, 8-lead JEDEC SOIC and 8-lead EIAJ SOIC Packages
Description
The AT25128A/256A provides 131,072/262,144 bits of serial electrically-erasable pro-
grammable read only memory (EEPROM) organized as 16,384/32,768 words of 8 bits
each. The device is optimized for use in many industrial and commercial applications
where low-power and low-voltage operation are essential. The devices are available in
space saving 8-lead PDIP, 8-lead JEDEC SOIC and 8-lead EIAJ SOIC (AT25256A)
packages. In addition, the entire family is available in 5.0V (4.5V to 5.5V) and 2.7V
(2.7V to 5.5V) versions.
Rev. 3404A–SEEPR–10/03
SPI Serial
Automotive
EEPROMs
128K (16,384 x 8)
256K (32,768 x 8)
AT25128A
AT25256A
Preliminary
Pin Configurations
Pin Name
Function
CS
Chip Select
SCK
Serial Data Clock
SI
Serial Data Input
SO
Serial Data Output
GND
Ground
VCC
Power Supply
WP
Write Protect
HOLD
Suspends Serial Input
NC
No Connect
DC
Don't Connect
8-lead PDIP
1
2
3
4
8
7
6
5
CS
SO
WP
GND
VCC
HOLD
SCK
SI
Document Outline
- Pin Configurations
- Features
- Description
- Absolute Maximum Ratings*
- Block Diagram
- Pin Capacitance(1)
- DC Characteristics
- AC Characteristics
- Serial Interface Description
- SPI Serial Interface
- Functional Description
- Timing Diagrams (for SPI Mode 0 (0, 0))
- AT25128A Ordering Information
- AT25256A Ordering Information
- Packaging Information