Features
• Low-voltage and Standard-voltage Operation
– 2.7 (VCC = 2.7V to 5.5V)
– 1.8 (VCC = 1.8V to 3.6V)
• Internally Organized 16,384 x 8 and 32,768 x 8
• Two-wire Serial Interface
• Schmitt Trigger, Filtered Inputs for Noise Suppression
• Bidirectional Data Transfer Protocol
• 1 MHz (5V), 400 kHz (2.7V, 2.5V) and 100 kHz (1.8V) Compatibility
• Write Protect Pin for Hardware and Software Data Protection
• 64-byte Page Write Mode (Partial Page Writes Allowed)
• Self-timed Write Cycle (5 ms Max)
Two-wire Serial
EEPROMs
• High Reliability
– Endurance: One Million Write Cycles
– Data Retention: 40 Years
• Extended Temperature and Lead-free/Halogen-free
Devices Available
• 8-lead JEDEC PDIP, 8-lead JEDEC and EIAJ SOIC, 8-lead MAP, 8-lead TSSOP, 8-lead
SAP and 8-ball dBGA2 Packages
128K (16,384 x 8)
256K (32,768 x 8)
• Die Sales: Wafer Form, Waffle Pack, and Bumped Wafers
Description
AT24C128(1)
AT24C256(2)
Notes: 1. Not recommended for
new design; please
refer to AT24C128B
datasheet.
The AT24C128/256 provides 131,072/262,144 bits of serial electrically erasable and
programmable read only memory (EEPROM) organized as 16,384/32,768 words of 8
bits each. The device’s cascadable feature allows up to 4 devices to share a common
Two-wire bus. The device is optimized for use in many industrial and commercial appli-
cations where low power and low voltage operation are essential. The devices are
available in space-saving 8-lead JEDEC PDIP, 8-lead JEDEC SOIC, 8-lead EIAJ
SOIC, 8-lead MAP (24C128), 8-lead TSSOP, 8-lead SOIC Array Package and 8-ball
dBGA2 packages. In addition, the entire family is available in 2.7V (2.7V to 5.5V) and
1.8V (1.8V to 3.6V) versions.
2. Not recommended for
new design; please
refer to AT24C256B
datasheet.
8-lead TSSOP
8-lead PDIP
Table 1. Pin Configuration
A0
A1
1
2
3
4
8
7
6
5
VCC
WP
A0
A1
1
2
3
4
8
7
6
5
VCC
WP
Pin Name
A0 - A1
SDA
Function
Address Inputs
Serial Data
Serial Clock Input
Write Protect
No Connect
Ground
NC
SCL
SDA
NC
SCL
SDA
GND
GND
SCL
8-lead SOIC
8-lead MAP
WP
VCC
8
7
6
5
1
2
3
4
A0
A0
A1
1
2
3
4
8
7
6
5
VCC
WP
NC
WP
SCL
SDA
A1
NC
GND
NC
SCL
SDA
GND
GND
Bottom View
8-lead SAP
8-ball dBGA2
8
7
6
5
1
2
3
4
A0
VCC
WP
VCC
WP
8
7
6
5
1
2
3
4
A0
A1
A1
NC
GND
SCL
SDA
SCL
SDA
NC
GND
Bottom View
Bottom View
0670T–SEEPR–3/07
1