Microchip Technology 24AA01T-I/ST

Overview

24AA01T-I/ST from Microchip Technology Inc. is a 1 Kbit I²C-compatible serial EEPROM organized as 128 × 8-bit memory with hardware write-protection, 400 kHz max clock frequency at 2.5–5.5 V, and industrial temperature range (−40°C to +85°C). It supports page writes up to 8 bytes and operates down to 1.7 V with standby current ≤1 µA, used for firmware parameter storage in embedded controllers.

For engineers reviewing the 24AA01T-I/ST datasheet, 24AA01T-I/ST pinout, 24AA01T-I/ST application, or 24AA01T-I/ST equivalent, key selection criteria include I²C bus compatibility at 1.7–5.5 V supply, WP-enabled hardware write protection, SOIC-8 package footprint, and guaranteed 1 million erase/write cycles with >200-year data retention.

Technical Context

The 24AA01T-I/ST implements a standard two-wire I²C interface with Schmitt-trigger inputs and slope-controlled outputs to suppress noise and eliminate ground bounce. Its internal address pointer enables current-address, random, and sequential read modes without external addressing logic.

It uses an on-chip HV generator for EEPROM programming and features self-timed write cycles with 5 ms maximum duration. The device ignores A0–A2 pins (no internal connection), simplifying board layout and eliminating address conflicts on shared I²C buses.

Key Specifications

Pinout & Package

24AA01T-I/ST is supplied in an 8-lead SOIC (Small Outline Integrated Circuit) package with 150 mil body width and standard 1.27 mm pitch. Pin 1 is marked by a beveled corner or notch; the package is RoHS-compliant and lead-free.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC01B-I/ST, the 24AA01T-I/ST enables lower-voltage operation critical for modern ultra-low-power MCUs, while 24AA02E48-I/ST adds cryptographic identity support at the cost of increased memory size and unit price - both require no PCB changes but serve distinct system-level security and voltage architecture needs.

Availability

24AA01T-I/ST is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and smart home gateway firmware requiring stable component supply and long-term lifecycle assurance.

Supply support for 24AA01T-I/ST 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 devices, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 24AA01T-I/ST belongs to Microchip's 24XX01 family of serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in cost-sensitive embedded systems where simplicity, robustness, and long-term data integrity are essential.

FAQ

What is the I²C address of the 24AA01T-I/ST?

The 24AA01T-I/ST uses a fixed 4-bit device code of '1010' followed by three "don't care" bits and a Read/Write bit, resulting in a 7-bit slave address of 0x50 for write and 0x51 for read operations. Pins A0–A2 have no internal connection and do not affect addressing - the 24AA01T-I/ST always responds to 0x50/0x51 regardless of their state.

Does the 24AA01T-I/ST support 1 MHz I²C operation?

No, the 24AA01T-I/ST supports a maximum clock frequency of 400 kHz at VCC ≥2.5 V and 100 kHz at 1.7 V ≤ VCC < 2.5 V. For 1 MHz operation, Microchip's 24FC01 family is required. The 24AA01T-I/ST's AC timing parameters (e.g., THIGH = 600 ns min) are specified only up to 400 kHz and do not guarantee reliable communication at higher speeds.

How does hardware write-protection work on the 24AA01T-I/ST?

When the WP pin of the 24AA01T-I/ST is tied to VCC, all write operations (byte and page) to the full 128-byte memory array (addresses 00h–7Fh) are inhibited; read operations remain fully functional. This protection is active immediately upon power-up and requires no software command - it is a purely hardware-level lock that survives reset and power cycling.

What is the maximum page write size for the 24AA01T-I/ST?

The 24AA01T-I/ST supports a page write buffer of exactly 8 bytes. Page writes must remain within a single physical page boundary (addresses 00h–07h, 08h–0Fh, etc.); crossing a boundary causes wraparound within the current page. Attempting to write more than 8 bytes before issuing a Stop condition overwrites earlier data in the buffer - the 24AA01T-I/ST does not support larger page sizes.

Is the 24AA01T-I/ST qualified for automotive applications?

No, the 24AA01T-I/ST carries the 'I' (Industrial) temperature grade (−40°C to +85°C) and is not AEC-Q100 qualified. While the broader 24XX01 family includes AEC-Q100-qualified variants (e.g., 24AA01HT-I/ST), the 24AA01T-I/ST part number specifically denotes industrial-grade qualification only - it lacks the extended testing, traceability, and documentation required for automotive use cases.