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25AA640A_12 Datasheet, PDF (1/36 Pages) Microchip Technology – 64K SPI Bus Serial EEPROM
25AA640A/25LC640A
64K SPI Bus Serial EEPROM
Device Selection Table
Part Number
25LC640A
25AA640A
VCC Range
2.5-5.5V
1.8-5.5V
Page Size
32 Byte
32 Byte
Temp. Ranges
I,E
I, E
Packages
P, SN, ST, MS, MF, MNY
P, SN, ST, MS, MF, MNY
Features:
• Max. Clock 10 MHz
• Low-Power CMOS Technology:
- Max. Write Current: 5 mA at 5.5V, 10 MHz
- Read Current: 5 mA at 5.5V, 10 MHz
- Standby Current: 1 A at 5.5V
• 8192 x 8-bit Organization
• 32 Byte Page
• Self-Timed Erase and Write Cycles (5 ms max.)
• Block Write Protection:
- Protect none, 1/4, 1/2 or all of array
• Built-In Write Protection:
- Power-on/off data protection circuitry
- Write enable latch
- Write-protect pin
• Sequential Read
• High Reliability:
- Endurance: 1,000,000 erase/write cycles
- Data retention: > 200 years
- ESD protection: > 4000V
• Temperature Ranges Supported:
- Industrial (I):
-40C to +85C
- Automotive (E):
-40°C to +125°C
Description:
The Microchip Technology Inc. 25AA640A/25LC640A
(25XX640A*) are 64 kbit Serial Electrically Erasable
PROMs. The memory is accessed via a simple Serial
Peripheral Interface (SPI) compatible serial bus. The
bus signals required are a clock input (SCK) plus
separate data in (SI) and data out (SO) lines. Access to
the device is controlled through a Chip Select (CS)
input.
Communication to the device can be paused via the
hold pin (HOLD). While the device is paused, transi-
tions on its inputs will be ignored, with the exception of
Chip Select, allowing the host to service higher priority
interrupts.
The 25XX640A is available in standard packages
including 8-lead PDIP and SOIC, and advanced
packaging including 8-lead MSOP, 8-lead TSSOP, DFN
and TDFN.
Package Types (not to scale)
TSSOP/MSOP
(ST, MS)
CS 1
SO 2
WP 3
VSS 4
8 VCC
7 HOLD
6 SCK
5 SI
PDIP/SOIC
(P, SN)
CS 1
SO 2
WP 3
VSS 4
8 VCC
7 HOLD
6 SCK
5 SI
X-Rotated TSSOP
(X/ST)
HOLD 1
VCC 2
CS 3
SO 4
8 SCK
7 SI
6 VSS
5 WP
DFN/TDFN
(MF/MNY)
CS 1
SO 2
WP 3
VSS 4
8 VCC
7 HOLD
6 SCK
5 SI
* 25XX640A is used in this document as a generic part number
for the 25AA640A, 25LC640A devices.
 2003-2013 Microchip Technology Inc.
DS21830F-page 1