25AA256/25LC256
256K SPI Bus Serial EEPROM
Device Selection Table
Part Number
VCC Range
Page Size
Temp. Ranges
Packages
25LC256
2.5-5.5V
64 Byte
I, E
P, SN, SM, ST, MF
25AA256
1.8-5.5V
64 Byte
I, E
P, SN, SM, ST, MF
Features:
Description:
• Max. Clock 10 MHz
• Low-Power CMOS Technology:
- Max. Write Current: 5 mA at 5.5V, 10 MHz
- Read Current: 6 mA at 5.5V, 10 MHz
- Standby Current: 1 A at 5.5V
• 32,768 x 8-bit Organization
• 64-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):
-40C to +85C
- Automotive (E):
-40°C to +125°C
The Microchip Technology Inc. 25AA256/25LC256
(25XX256*) are 256 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,
transitions on its inputs will be ignored, with the
exception of Chip Select, allowing the host to service
higher priority interrupts.
The 25XX256 is available in standard packages including 8-lead PDIP and SOIC, and advanced packaging
including 8-lead DFN and 8-lead TSSOP.
Package Types (not to scale)
DFN
PDIP/SOIC
(MF)
(P, SN, SM)
CS 1
8
VCC
SO 2
7
HOLD
WP 3
6
VSS 4
5
• Pb-Free and RoHS Compliant
CS
SO
Function
Chip Select Input
Serial Data Output
WP
Write-Protect
VSS
Serial Clock Input
HOLD
VCC
Hold Input
Supply Voltage
* 25XX256 is used in this document as a generic part number
for the 25AA256/25LC256 devices.
2003-2013 Microchip Technology Inc.
HOLD
SCK
WP
3
6
SCK
SI
VSS
4
5
SI
1
8
SCK
VCC
2
7
SI
CS
3
6
VSS
SO
4
5
WP
TSSOP
Serial Data Input
SCK
8
7
HOLD
Ground
SI
1
2
Rotated TSSOP
(ST)
Pin Function Table
Name
VCC
CS
SO
(ST)
CS
1
8
VCC
SO
2
7
HOLD
WP
3
6
SCK
VSS
4
5
SI
DS21822G-page 1
