Microchip Technology 24AA025E64T-E/SN

Overview

24AA025E64T-E/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 features 16-byte page write capability. Used for secure device identity storage in networked embedded systems requiring IEEE-compliant MAC addressing.

For engineers reviewing the 24AA025E64T-E/SN datasheet, 24AA025E64T-E/SN pinout, 24AA025E64T-E/SN application, or 24AA025E64T-E/SN equivalent, key selection criteria include EUI-64™ pre-programming integrity, industrial-grade temperature range (−40°C to +85°C), 6-lead SOT-23 package compatibility, and cascading support for multi-device I²C bus configurations.

Technical Context

The 24AA025E64T-E/SN implements a two-block 128 × 8-bit EEPROM array with hardware-enforced write protection on upper half (0x80–0xFF), preserving the pre-programmed EUI-64™ address. Its I²C slave interface uses Schmitt-trigger inputs and slope-controlled outputs to suppress noise and eliminate ground bounce on shared buses.

It supports cascaded addressing via A0/A1 inputs (A2 not connected in 6-lead SOT-23), enabling up to four devices on one bus. Internal acknowledge polling allows host firmware to detect write completion without fixed delays, improving bus throughput during configuration writes.

Key Specifications

Pinout & Package

Package: 6-lead SOT-23 (Microchip drawing C04-057-SN), 1.6 mm × 2.8 mm footprint, surface-mount, RoHS-compliant matte tin finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar serial EEPROM with pre-programmed node identity applications.

Compared with 24AA025E64T-E/SN, the 24AA02E64T-I/SN sacrifices cascading capability for SOIC ease-of-handling, while the AT24MAC402-MAHM-T trades EUI-64™ and page size for lower unit cost - making 24AA025E64T-E/SN optimal for compact, multi-node industrial designs demanding full IEEE 64-bit compliance.

Availability

24AA025E64T-E/SN is available at Aetrix Electronics and suitable for industrial automation, automotive telematics, and medical device manufacturing requiring stable component supply across extended product lifecycles.

Supply support for 24AA025E64T-E/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 components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA02XEXX family was designed specifically for embedded systems requiring guaranteed-unique, factory-provisioned network identities - targeting industrial IoT, automotive ECUs, and regulated medical equipment where software-based MAC generation is insecure or noncompliant.

FAQ

What is the exact memory organization and write-protect behavior of the 24AA025E64T-E/SN?

The 24AA025E64T-E/SN contains 256 bytes (2 Kbit) of EEPROM arranged as two 128-byte blocks. The upper half (addresses 0x80–0xFF) is permanently write-protected to preserve the factory-programmed EUI-64™ node address (stored at 0xF8–0xFF). Only the lower half (0x00–0x7F) is user-writable. This hardware lock prevents accidental or malicious overwrites of identity data, ensuring long-term integrity of the 24AA025E64T-E/SN's core function.

How does the 24AA025E64T-E/SN support multiple devices on the same I²C bus?

The 24AA025E64T-E/SN supports cascading via its A0 and A1 pins, which configure bits A0 and A1 of the 7-bit I²C slave address (A2 is not connected in the 6-lead SOT-23 package). By tying A0/A1 to VSS or VCC, up to four distinct 24AA025E64T-E/SN devices can share one I²C bus. Each responds only to its assigned address, enabling compact multi-sensor nodes or modular systems to maintain individual EUI-64™ identities without bus contention.

What are the timing and voltage requirements for reliable I²C communication with the 24AA025E64T-E/SN?

The 24AA025E64T-E/SN supports standard-mode (100 kHz) and fast-mode (400 kHz) I²C operation. At VCC ≥ 2.5V, it accepts 400 kHz clock with minimum high/low times of 600 ns/1300 ns. Below 2.5V, maximum clock drops to 100 kHz with extended timing (4 µs high/low). Input thresholds follow standard I²C levels (VIH = 0.7×VCC, VIL = 0.3×VCC), and Schmitt-trigger inputs ensure noise immunity - critical for stable 24AA025E64T-E/SN operation in electrically noisy environments.

Can the pre-programmed EUI-64™ address in the 24AA025E64T-E/SN be modified or reprogrammed?

No. The EUI-64™ address in the 24AA025E64T-E/SN is factory-programmed into the write-protected upper memory block (0xF8–0xFF) and cannot be altered in-system or during programming. This permanent, globally unique identifier is certified by IEEE and guaranteed collision-free across all Microchip-manufactured units. The 24AA025E64T-E/SN's hardware write protection ensures the address remains intact through power cycles, firmware updates, and environmental stress - fulfilling strict identity assurance requirements.

What package and marking details confirm authenticity of the 24AA025E64T-E/SN?

The 24AA025E64T-E/SN is supplied in a 6-lead SOT-23 package (Microchip drawing C04-057-SN) with matte tin (Sn) finish. Top-side marking follows 2-line format: first line "AAACY", second line "4A25E64I" for industrial temp or "4A25E64E" for automotive temp, plus year/week/traceability codes. The "T-E/SN" suffix explicitly denotes tape-and-reel packaging in SOT-23 with industrial temperature grade - verifying correct variant against Microchip's official DS20002124H datasheet.