AT24C64B 2-Wire Serial EEPROM

Atmel Memory & Storage — specifications, applications, sourcing support and RFQ.

AT24C64B 2-Wire Serial EEPROM

RFQ Available Sourcing Support Alternative Matching RoHS
Part Number
AT24C64B
Manufacturer
Atmel
Package
8-lead TSSOP
Category
Memory & Storage
Product Type
Serial EEPROM

Quick Sourcing Note

AT24C64B from Atmel is a Memory & Storage component supplied as a 2-wire serial EEPROM in an 8-lead TSSOP package. It provides 64 Kbit, or 65,536 bits, organized as 8,192 x 8 with 256 pages of 32 bytes. The device supports a 400 kHz maximum SCL clock, a 2.7 V to 5.5 V recommended supply range, and operation from -40°C to +125°C. It is suited for nonvolatile parameter, configuration, calibration, and addressable data storage on a 2-wire serial bus, with 32-byte page writes, 5 ms maximum write cycle time, 1,000,000 characterized write cycles, and 100-year data retention.

Specifications

TypeDescription
Part NumberAT24C64B
ManufacturerAtmel
Product TypeSerial EEPROM
CategoryMemory & Storage
Package / Case8-lead TSSOP
Memory Density64 Kbit / 65,536 bits; organized as 8,192 x 8
Memory Organization8,192 words x 8 bits; internal organization
Page Organization256 pages x 32 bytes; 64K Serial EEPROM
Page Write Size32 bytes; partial page writes allowed
Random Address Width13-bit data word address; random word addressing
Interface2-wire serial interface; serial EEPROM access interface
Clock Frequency400 kHz max; SCL
Supply Voltage2.7 V min, 5.5 V max; recommended operating range
Operating Temperature Range-40°C to +125°C; automotive temperature range / recommended operating range
Absolute Operating Temperature-55°C to +125°C; absolute maximum rating
Storage Temperature-65°C to +150°C; absolute maximum rating
Voltage on Any Pin-1.0 V to +7.0 V; with respect to ground, absolute maximum rating
Maximum Operating Voltage6.25 V; absolute maximum rating
DC Output Current5.0 mA; absolute maximum rating
SDA Input/Output Capacitance8 pF max; TA=25°C, f=1.0MHz, VCC=5.5V, VI/O=0V; characterized, not 100% tested
Input Capacitance6 pF max; A0, A1, A2, SCL; TA=25°C, f=1.0MHz, VCC=5.5V, VIN=0V; characterized, not 100% tested
Read Supply Current0.4 mA typ, 1.0 mA max; VCC=5.0V, read at 400kHz
Write Supply Current2.0 mA typ, 3.0 mA max; VCC=5.0V, write at 400kHz
Standby Current1.0 µA typ, 3.0 µA max; VCC=2.7V, VIN=VCC or VSS
Standby Current3.0 µA typ, 5.0 µA max; VCC=5.0V, VIN=VCC or VSS
Input Leakage Current0.10 µA typ, 3.0 µA max; VIN=VCC or VSS
Output Leakage Current0.05 µA typ, 3.0 µA max; VOUT=VCC or VSS
Input Low Level-0.6 V min, VCC x 0.3 max; reference only, not tested
Input High LevelVCC x 0.7 min, VCC + 0.5 V max; reference only, not tested
Output Low Level0.4 V max; VCC=3.0V, IOL=2.1mA
Output Low Level0.2 V max; VCC=1.8V, IOL=0.15mA
Clock Pulse Width Low1.2 µs min; SCL timing, TA=-40°C to +125°C, VCC=2.7V to 5.5V, CL=1 TTL gate and 100pF
Clock Pulse Width High0.6 µs min; SCL timing, TA=-40°C to +125°C, VCC=2.7V to 5.5V, CL=1 TTL gate and 100pF
Noise Suppression Time50 ns max; characterized only
Clock Low to Data Out Valid0.1 µs min, 0.9 µs max; tAA
Bus Free Time Before New Transmission1.2 µs min; tBUF; characterized only
Start Hold Time0.6 µs min; tHD.STA
Start Set-up Time0.6 µs min; tSU.STA
Data In Hold Time0 µs min; tHD.DAT
Data In Set-up Time100 ns min; tSU.DAT
Input Rise Time0.3 µs max; tR; characterized only
Input Fall Time300 ns max; tF; characterized only
Stop Set-up Time0.6 µs min; tSU.STO
Data Out Hold Time50 ns min; tDH
Write Cycle Time5 ms max; self-timed write cycle, tWR
Endurance1,000,000 write cycles; 5.0V, 25°C, page mode; characterized only
Data Retention100 years; high reliability feature
Cascadable DevicesUp to 8 devices on one bus; using A2, A1, A0 device address inputs
Device Address Format1010 A2 A1 A0 R/W; 8-bit device address word for 64K EEPROM
Write ProtectionUpper quadrant write protected; WP pin at VCC inhibits writes to upper quadrant; WP at GND allows normal writes
Datasheet Statusrequest_only

Product Overview

The Atmel AT24C64B is a 64 Kbit 2-wire serial EEPROM for Memory & Storage applications. Its internal array is organized as 8,192 words x 8 bits, giving a total capacity of 65,536 bits. The 64K device uses 256 pages of 32 bytes, and partial page writes are allowed within the 32-byte page write structure.

Serial access uses a 2-wire interface with SCL operation up to 400 kHz. Random word addressing uses a 13-bit data word address, while the device address format is 1010 A2 A1 A0 R/W. The A2, A1, and A0 address inputs allow up to eight devices on one bus.

The device operates from 2.7 V to 5.5 V over the -40°C to +125°C automotive temperature range and is offered in an 8-lead TSSOP package. Electrical limits include 0.4 mA typical read current at 5.0 V and 400 kHz, 2.0 mA typical write current under the same clock condition, and standby current ratings at both 2.7 V and 5.0 V. The WP pin supports upper-quadrant write protection when tied to VCC.

Key Features

  • 64 Kbit EEPROM organized as 8,192 x 8
  • 256 pages with 32-byte page write size
  • 2-wire serial interface with 400 kHz SCL maximum
  • 2.7 V to 5.5 V recommended supply range
  • -40°C to +125°C automotive operating range
  • 13-bit random word addressing
  • Up to eight devices on one serial bus
  • Upper-quadrant write protection through WP pin
  • 5 ms maximum self-timed write cycle
  • 100-year data retention rating

Typical Applications

  • Nonvolatile configuration storage
  • Calibration data storage
  • Serial bus parameter memory
  • Addressable system data storage
  • Automotive temperature EEPROM designs
  • Multi-device 2-wire memory buses

Procurement Notes

When requesting a quote for AT24C64B, buyers should confirm the manufacturer, package or case, required quantity, target date code, compliance documents, packing method, destination country and expected delivery schedule.

If alternatives are acceptable, buyers should share the approved vendor list, required electrical or optical limits, package constraints and qualification requirements. Any alternative part should be reviewed by the buyer's engineering team before production use.

For memory and storage sourcing, density, organization, speed grade, voltage, package, temperature grade, date code, lifecycle status and original packing condition should be verified before approval.

FAQ

What memory density does the AT24C64B provide?

The AT24C64B provides 64 Kbit, or 65,536 bits, of EEPROM memory. The internal memory organization is 8,192 words x 8 bits, and the page organization is 256 pages x 32 bytes.

What serial interface and clock rate does AT24C64B use?

The device uses a 2-wire serial interface for EEPROM access. The SCL clock frequency is specified at 400 kHz maximum under the listed timing conditions for the -40°C to +125°C operating range.

What supply and temperature ranges apply to this EEPROM?

The recommended operating supply range is 2.7 V to 5.5 V. The operating temperature range is -40°C to +125°C for the automotive temperature range, with separate absolute maximum temperature and storage ratings listed in the datasheet facts.

How does write protection work on the AT24C64B?

The WP pin controls upper-quadrant write protection. With WP at VCC, writes to the upper quadrant are inhibited. With WP at GND, normal writes are allowed according to the extracted device description.

Technical Review & Sourcing Note

Prepared by LDeepAI Component Sourcing Team. Reviewed for RFQ, documentation and alternative sourcing use. Last updated: June 30, 2026.

This page is based on manufacturer datasheet information and LDeepAI sourcing review. Specifications should be verified against the official manufacturer datasheet before final procurement or design approval. Final electrical, optical and reliability approval should be confirmed by the buyer's engineering team.

Request Quote Request Datasheet