M
Part
Number
24AA256
24LC256
†
100
24AA256/24LC256
PACKAGE TYPE
PDIP
256K I
2
C
™
CMOS Serial EEPROM
DEVICE SELECTION TABLE
V
CC
Range
1.8-5.5V
2.5-5.5V
Max Clock
Frequency
400 kHz
†
400 kHz
‡
Temp
Ranges
I
I, E
A0
A1
A2
Vss
1
8
Vcc
WP
SCL
SDA
24xx256
2
3
4
7
6
5
kHz for V
CC
< 2.5V.
‡
100 kHz for E temperature range.
FEATURES
• Low power CMOS technology
- Maximum write current 3 mA at 5.5V
- Maximum read current 400
µ
A at 5.5V
- Standby current 100 nA typical at 5.5V
• 2-wire serial interface bus, I
2
C compatible
• Cascadable for up to eight devices
• Self-timed ERASE/WRITE cycle
• 64-byte page-write mode available
• 5 ms max write-cycle time
• Hardware write protect for entire array
• Schmitt trigger inputs for noise suppression
• 100,000 erase/write cycles guaranteed
• Electrostatic discharge protection > 4000V
• Data retention > 200 years
• 8-pin PDIP and SOIC (208 mil) packages
• Temperature ranges:
- Industrial (I):
-40
°
C to +85
°
C
- Automotive (E):
-40
°
C to +125
°
C
SOIC
A0
A1
A2
V
SS
1
8
V
CC
WP
SCL
SDA
24xx256
2
3
4
7
6
5
BLOCK DIAGRAM
A0…A2
WP
HV GENERATOR
I/O
CONTROL
LOGIC
MEMORY
CONTROL
LOGIC
XDEC
EEPROM
ARRAY
PAGE LATCHES
DESCRIPTION
The Microchip Technology Inc. 24AA256/24LC256
(24xx256*) is a 32K x 8 (256K bit) Serial Electrically
Erasable PROM, capable of operation across a broad
voltage range (1.8V to 5.5V). It has been developed for
advanced, low power applications such as personal
communications or data acquisition. This device also
has a page-write capability of up to 64 bytes of data.
This device is capable of both random and sequential
reads up to the 256K boundary. Functional address
lines allow up to eight devices on the same bus, for up
to 2 Mbit address space. This device is available in the
standard 8-pin plastic DIP, and 8-pin SOIC (208 mil)
packages.
I/O
SCL
YDEC
SDA
V
CC
V
SS
SENSE AMP
R/W CONTROL
I
2
C is a trademark of Philips Corporation.
*24xx256 is used in this document as a generic part number for the 24AA256/24LC256 devices.
©
1998 Microchip Technology Inc.
DS21203C-page 1
MICROCHIP [ MICROCHIP TECHNOLOGY ]
