25AA040/25LC040/25C040
M
™
4K SPI Bus Serial EEPROM
PACKAGE TYPES
DEVICE SELECTION TABLE
Part
Number
VCC
Range
Max Clock
Frequency
Temp
Ranges
PDIP/SOIC
1
2
3
4
8
7
6
5
VCC
HOLD
SCK
SI
CS
SO
25AA040
25LC040
25C040
1.8-5.5V
2.5-5.5V
4.5-5.5V
1 MHz
2 MHz
3 MHz
C,I
C,I
C,I,E
WP
VSS
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
TSSOP
1
2
3
4
8
7
6
5
SCK
SI
VSS
WP
HOLD
VCC
CS
• 16 byte page
• Write cycle time: 5ms max.
• Self-timed ERASE and WRITE cycles
• Block write protection
SO
- Protect none, 1/4, 1/2, or all of array
• Built-in write protection
- Power on/off data protection circuitry
- Write enable latch
BLOCK DIAGRAM
Status
Register
- Write protect pin
• Sequential read
HV Generator
• High reliability
- Endurance: 10M cycles (guaranteed)
- Data retention: > 200 years
- ESD protection: > 4000 V
• 8-pin PDIP, SOIC, and TSSOP packages
• Temperature ranges supported:
EEPROM
Array
Memory
Control
Logic
X
I/O Control
Logic
- Commercial: (C)
- Industrial: (I)
0°C to +70°C
-40°C to +85°C
-40°C to +125°C
Dec
- Automotive: (E) (25C040)
Page Latches
DESCRIPTION
SI
The Microchip Technology Inc. 25AA040/25LC040/
25C040 (25xx040 ) is a 4K bit serial Electrically Eras-
*
Y Decoder
SO
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.
CS
SCK
Sense Amp.
R/W Control
HOLD
WP
VCC
VSS
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).
*25xx040 is used in this document as a generic part number for the 25AA040/25LC040/25C040 devices.
SPI is a trademark of Motorola.
1997 Microchip Technology Inc.
Preliminary
DS21204A-page 1