Rainbow Electronics AT25640A User Manual
Features, Description

1
Features
•
Serial Peripheral Interface (SPI) Compatible
•
Supports SPI Modes 0 (0,0) and 3 (1,1)
– Data Sheet Describes Mode 0 Operation
•
Medium-voltage and Standard-voltage Operation
– 5.0 (V
CC
= 4.5V to 5.5V)
– 2.7 (V
CC
= 2.7V to 5.5V)
•
5.0 MHz Clock Rate (5V)
•
32-byte Page Mode
•
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 (2 ms [5V] typical)
•
High Reliability
– Endurance: One Million Write Cycles
– Data Retention: 100 Years
•
8-lead PDIP and 8-lead JEDEC SOIC Packages
Description
The AT25080A/160A/320A/640A provides 8192/16384/32768/65536 bits of serial
electrically-erasable programmable read-only memory (EEPROM) organized as
1024/2048/4096/8192 words of 8 bits each. The device is optimized for use in many
automotive applications where low-power and low-voltage operation are essential.
The AT25080A/160A/320A/640A is available in space saving 8-lead PDIP and 8-lead
JEDEC SOIC packages.
The AT25080A/160A/320A/640A is enabled through the Chip Select pin (CS) and
accessed via a three-wire interface consisting of Serial Data Input (SI), Serial Data
Output (SO), and Serial Clock (SCK). All programming cycles are completely self-
timed, and no separate erase cycle is required before write.
Block write protection is enabled by programming the status register with one of four blocks
of write protection. Separate program enable and program disable instructions are provided
for additional data protection. Hardware data protection is provided via the WP pin to protect
against inadvertent write attempts to the status register. The HOLD pin may be used to sus-
pend any serial communication without resetting the serial sequence.
Table 1. Pin Configuration
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
SPI Serial
Automotive
EEPROMs
8K (1024 x 8)
16K (2048 x 8)
32K (4096 x 8)
64K (8192 x 8)
AT25080A
AT25160A
AT25320A
AT25640A
3401C–SEEPR–8/04
1
2
3
4
8
7
6
5
CS
SO
WP
GND
VCC
HOLD
SCK
SI
1
2
3
4
8
7
6
5
CS
SO
WP
GND
VCC
HOLD
SCK
SI
8-lead PDIP
8-lead SOIC