© 2006 Microchip Technology Inc. DS21204E-page 1
25AA040/25LC040/25C040
Device Selection Table
Features:
• Low-power CMOS technology:
- Write current: 3 mA, typical
- Read current: 500 μA, typical
- Standby current: 500 nA, typical
• 512 x 8-bit organization
• 16 byte page
• Write cycle time: 5 ms max.
• Self-timed Erase and Write cycles
• 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: 1M cycles
- Data retention: > 200 years
- ESD protection: > 4000V
• 8-pin PDIP, SOIC and TSSOP packages
• Temperature ranges supported:
Description:
The Microchip Technology Inc. 25AA040/25LC040/
25C040 (25XX040
*
) is a 4 Kbit serial Electrically
Erasable PROM. 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. Also, write operations to the device can be
disabled via the write-protect pin (WP).
Package Types
Block Diagram
Part
Number
VCC
Range
Max. Clock
Frequency
Temp.
Ranges
25AA040 1.8-5.5V 1 MHz I
25LC040 2.5-5.5V 2 MHz I
25C040 4.5-5.5V 3 MHz I,E
- Industrial (I): -40°Cto +85°C
- Automotive (E) (25C040): -40°C to +125°C
CS
SO
WP
VSS
VCC
HOLD
SCK
SI
1
2
3
4
8
7
6
5
25XX040
CS
SO
WP
VSS
VCC
HOLD
SCK
SI
1
2
3
4
8
7
6
5
25XX040
HOLD
VCC
CS
SO
1
2
3
4
8
7
6
5
SCK
SI
V
SS
WP
25XX040
PDIP
SOIC
TSSOP
SI
SO
SCK
CS
HOLD
WP
STATUS
Register
I/O Control
Memory
Control
Logic
HV Generator
EEPROM
Array
Page
Y Decoder
Sense Amp.
R/W Control
Logic
VCC
VSS
XDEC
Latches
4K SPI Bus Serial EEPROM
*25XX040 is used in this document as a generic part number
for the 25AA040/25LC040/25C040 devices.
Not recommended for new designs –
Please use 25AA040A or 25LC040A.
