AT24C256B_07 Datasheet, PDF (1/21 Pages) ATMEL Corporation – Two-wire Serial EEPROM 256K (32,768 x 8)

Features
• Low-voltage and Standard-voltage Operation
– 1.8 (V_CC = 1.8V to 3.6V)
• Internally Organized as 32,768 x 8
• Two-wire Serial Interface
• Schmitt Trigger, Filtered Inputs for Noise Suppression
• Bidirectional Data Transfer Protocol
• 1 MHz (3.6V, 2.7V, 2.5V), and 400 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)
• High Reliability
– Endurance: One Million Write Cycles
– Data Retention: 40 Years
• Lead-free/Halogen-free Devices Available
• 8-lead JEDEC PDIP, 8-lead JEDEC SOIC, EIAJ SOIC, 8-lead MAP, 8-lead Ultra Thin
Small Array Package (SAP), 8-lead TSSOP, and 8-ball dBGA2 Packages
• Die Sales: Wafer Form, Waffle Pack and Bumped Wafers
Description
The AT24C256B provides 262,144 bits of serial electrically erasable and programma-
ble read-only memory (EEPROM) organized as 32,768 words of 8 bits each. The
device’s cascadable feature allows up to eight devices to share a common two-wire
bus. The device is optimized for use in many industrial and commercial applications
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 MAP, 8-lead Ultra
Thin SAP, 8-lead TSSOP, and 8-ball dBGA2 packages. In addition, the entire family is
available in a 1.8V (1.8V to 3.6V) version.
Two-wire Serial
EEPROM
256K (32,768 x 8)
AT24C256B
Table 1. Pin Configurations
Pin Name
A0–A2
SDA
SCL
WP
NC
GND
Function
Address Inputs
Serial Data
Serial Clock Input
Write Protect
No Connect
Ground
8-lead PDIP
A0 1
A1 2
A2 3
GND 4
8 VCC
A0
7 WP
A1
6 SCL
A2
5 SDA GND
8-lead SOIC
1
8
2
7
3
6
4
5
VCC
WP
SCL
SDA
8-lead dBGA2
VCC 8
WP 7
SCL 6
SDA 5
1 A0
2 A1
3 A2
4 GND
Bottom View
8-lead Ultra Thin SAP
VCC 8
WP 7
SCL 6
SDA 5
1 A0
2 A1
3 A2
4 GND
Bottom View
8-lead TSSOP
A0 1
A1 2
A2 3
GND 4
8 VCC
7 WP
6 SCL
5 SDA
8-lead MAP
VCC 8
WP 7
SCL 6
SDA 5
1 A0
2 A1
3 A2
4 GND
Bottom View
Rev. 5080B–SEEPR–1/07
1