1997 Microchip Technology Inc.
Preliminary
DS21204A-page 1
M
25AA040/25LC040/25C040
DEVICE SELECTION TABLE
FEATURES
Low power CMOS technology
- Write current: 3 mA typical
- Read current: 500
- Standby current: 500 nA typical
512 x 8 bit organization
16 byte page
Write cycle time: 5ms 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: 10M cycles (guaranteed)
- Data retention: > 200 years
- ESD protection: > 4000 V
8-pin PDIP, SOIC, and TSSOP packages
Temperature ranges supported:
- Commercial: (C)
- Industrial: (I)
- Automotive: (E) (25C040)
μ
A typical
DESCRIPTION
The Microchip Technology Inc. 25AA040/25LC040/
25C040 (25xx040
) is a 4K bit serial Electrically Eras-
able 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
25AA040
25LC040
25C040
V
CC
Range
1.8-5.5V
2.5-5.5V
4.5-5.5V
Max Clock
Frequency
1 MHz
2 MHz
3 MHz
Temp
Ranges
C,I
C,I
C,I,E
0
°
°
°
C to
C to
C to +125
+70
+85
°
°
°
C
C
C
-40
-40
2
TSSOP
1
2
3
4
8
7
6
5
SCK
SI
V
SS
WP
HOLD
V
CC
CS
SO
2
PDIP/SOIC
1
2
3
4
8
7
6
5
V
CC
HOLD
SCK
SI
CS
SO
WP
V
SS
SI
SO
SCK
CS
HOLD
WP
Status
Register
I/O Control
Logic
Memory
Control
Logic
X
Dec
HV Generator
EEPROM
Array
Page Latches
Y Decoder
Sense Amp.
R/W Control
CC
V
SS
4K SPI
Bus Serial EEPROM
*25xx040 is used in this document as a generic part number for the 25AA040/25LC040/25C040 devices.
SPI is a trademark of Motorola.