Microchip Technology 24AA025E64-I/SN

Overview

24AA025E64-I/SN from Microchip Technology Inc. is a 2 Kbit I²C-compatible serial EEPROM with factory-programmed, globally unique EUI-64™ node address stored in write-protected memory (0xF8–0xFF). It operates from 1.7V to 5.5V, supports 400 kHz I²C clock (100 kHz at VCC < 2.5V), and delivers 1 µA max standby current (I-temp) for low-power embedded identity storage in networked devices.

For engineers reviewing the 24AA025E64-I/SN datasheet, 24AA025E64-I/SN pinout, 24AA025E64-I/SN application, or 24AA025E64-I/SN equivalent, key selection criteria include EUI-64™ pre-programming integrity, 16-byte page write capability, I²C bus noise immunity via Schmitt-trigger inputs, and industrial temperature support (−40°C to +85°C) in 8-lead SOIC package.

Technical Context

The 24AA025E64-I/SN implements a two-block 128 × 8-bit EEPROM array with hardware-enforced write protection on upper half (0x80–0xFF), where the EUI-64™ address resides. Its I²C slave interface uses open-drain SDA/SCL with internal slope control and 50 ns input filter spike suppression to ensure robust operation on noisy PCBs.

Addressing supports cascading up to eight devices via A0/A1/A2 chip-select bits (A2 not connected in 6-lead SOT-23); for the 8-lead SOIC variant (I/SN), all three pins are functional and must be tied to VSS or VCC. Page write buffer holds 16 bytes, with self-timed 5 ms typical erase/write cycle and acknowledge polling for bus efficiency.

Key Specifications

Pinout & Package

Package: 8-lead SOIC (SN), 3.90 mm body width, RoHS-compliant matte tin finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar EEPROM identity storage applications.

Compared with 24AA025E64-I/SN, the 24AA02E64-I/SN offers identical package and voltage specs but lacks EUI-64™ and cascading capability, while AT24C02C-SSHM-T provides raw EEPROM capacity without identity features-making 24AA025E64-I/SN the only choice for plug-and-play IEEE-compliant node identity in industrial I²C designs.

Availability

24AA025E64-I/SN is available at Aetrix Electronics and suitable for industrial Ethernet node identity, smart sensor device authentication, medical diagnostic equipment calibration, and automotive telematics module ID requiring stable component supply across extended product lifecycles.

Supply support for 24AA025E64-I/SN includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microchip Technology Inc. is a leading provider of microcontrollers, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA025E64-I/SN belongs to Microchip's 24AA02XEXX family of pre-programmed serial EEPROMs designed specifically for secure, standards-compliant device identity in industrial, automotive, and IoT edge nodes.

FAQ

What is the exact memory organization of the 24AA025E64-I/SN?

The 24AA025E64-I/SN contains 2 Kbit (256 × 8) of EEPROM arranged in two 128-word blocks. The upper half (addresses 0x80–0xFF) is permanently write-protected and stores the factory-programmed EUI-64™ node address (0xF8–0xFF). The lower half (0x00–0x7F) is user-programmable for application data. This layout ensures identity integrity while enabling flexible configuration storage in the 24AA025E64-I/SN.

Does the 24AA025E64-I/SN support I²C multi-master arbitration?

No, the 24AA025E64-I/SN operates exclusively as an I²C slave device and does not implement multi-master arbitration logic. It responds only to its assigned 7-bit slave address (1010xxx0/1) and relies on the master controller to manage bus contention. The 24AA025E64-I/SN includes Schmitt-trigger inputs and slope control to maintain signal integrity during shared-bus operation, but arbitration responsibility lies entirely with the master - consistent with standard I²C EEPROM behavior.

How is the EUI-64™ address protected from overwrite in the 24AA025E64-I/SN?

The EUI-64™ address in the 24AA025E64-I/SN is stored in the upper half of memory (0xF8–0xFF) and protected by permanent hardware write-protection. Any write attempt to addresses 0x80–0xFF is ignored - the 24AA025E64-I/SN returns no ACK and discards the data. This protection is implemented at silicon level and cannot be disabled via software or voltage manipulation, ensuring the globally unique identity remains intact over the full 200-year data retention period.

Can the 24AA025E64-I/SN be used in automotive applications requiring AEC-Q200 qualification?

No, the 24AA025E64-I/SN carries the "I" (Industrial) temperature grade (−40°C to +85°C) and is not AEC-Q200 qualified. For automotive applications, Microchip offers the "E" grade variant 24AA025E64-E/SN, rated for −40°C to +125°C and qualified to AEC-Q200 Rev D. The 24AA025E64-I/SN is intended for industrial, medical, and commercial systems where extended temperature and stress testing per AEC-Q200 are not required.

What is the maximum number of 24AA025E64-I/SN devices supported on a single I²C bus?

Up to eight 24AA025E64-I/SN devices can be connected to one I²C bus using the A0, A1, and A2 chip-select pins in the 8-lead SOIC (I/SN) package. Each device is assigned a unique 3-bit address combination (000–111), forming distinct 7-bit slave addresses (1010xxx0/1). The 24AA025E64-I/SN's A2 pin is functional in SOIC, enabling full 8-device cascading - unlike the SOT-23 variant which supports only four devices due to missing A2.