Microchip Technology 24AA01/P

Overview

24AA01/P from Microchip Technology Inc. is a 1 Kbit I²C-compatible serial EEPROM organized as 128 × 8-bit memory, operating from 1.7V to 5.5V with industrial temperature range (–40°C to +85°C). It features hardware write-protection via the WP pin, 8-byte page write buffer, and Schmitt-trigger inputs for noise immunity-used in embedded system configuration storage, sensor calibration data retention, and firmware parameter backup.

For engineers reviewing the 24AA01/P datasheet, 24AA01/P pinout, 24AA01/P application, or 24AA01/P equivalent, key selection criteria include its 400 kHz max I²C clock (100 kHz below 2.5V), 5 ms max page write time, 1 µA standby current, and PDIP-8 package compatibility with legacy through-hole designs.

Technical Context

The 24AA01/P implements a two-wire I²C interface with fixed 7-bit device address prefix '1010' and three don't-care bits, enabling single-device addressing on shared buses. Its internal architecture includes an 8-byte page latch, HV generator for EEPROM programming, and address pointer that auto-increments during sequential reads.

Write protection is implemented via a dedicated WP pin: tied to VSS for full read/write access, or VCC to lock the entire 00h–7Fh memory array. All I/O pins feature Schmitt-trigger inputs and output slope control to suppress ground bounce and ensure robust operation in electrically noisy environments.

Key Specifications

Pinout & Package

24AA01/P is supplied in an 8-lead plastic dual in-line package (PDIP), 300 mil body width, with through-hole mounting. Pin 1 is marked by a notch or dot; leads are gull-wing shaped with standard 0.100" pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA01/P, 24LC01B/P lacks 1.7V operation but offers identical packaging and timing for higher-voltage systems, while AT24C01C-PUM adds 1 MHz capability and alternate addressing-making it suitable for performance-sensitive or multi-vendor BOM strategies.

Availability

24AA01/P is available at Aetrix Electronics and suitable for industrial sensor calibration, medical device configuration, automotive body control modules, and consumer appliance settings storage requiring stable component supply and long-term obsolescence management.

Supply support for 24AA01/P 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 microcontroller, analog, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 24AA01/P belongs to Microchip's 24XX01 family of I²C EEPROMs, designed specifically for low-power, space-constrained embedded systems requiring reliable, byte-addressable nonvolatile storage with minimal external components.

FAQ

What is the maximum I²C clock frequency supported by the 24AA01/P?

The 24AA01/P supports up to 400 kHz when VCC is 2.5V to 5.5V, and 100 kHz when VCC is 1.7V to less than 2.5V. This dual-speed capability ensures interoperability across 1.8V, 3.3V, and 5V host systems while maintaining I²C protocol compliance. The 24AA01/P does not support 1 MHz operation-unlike the 24FC01 variant.

Does the 24AA01/P require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA01/P requires external pull-up resistors on both SDA and SCL because its I/O pins are open-drain. Typical values are 10 kΩ for 100 kHz operation and 2 kΩ for 400 kHz. Proper pull-up strength ensures signal rise times meet I²C timing specifications-especially critical under capacitive bus loading or extended trace lengths.

How does the WP pin function on the 24AA01/P?

On the 24AA01/P, the WP (Write-Protect) pin provides hardware-level memory lock: when tied to VCC, all write operations to the 00h–7Fh address range are inhibited while read operations remain fully functional. When tied to VSS (or left floating, though not recommended), normal read/write access is enabled. This feature prevents accidental overwrites during power transitions or firmware errors.

Can the 24AA01/P be used in automotive applications?

The 24AA01/P itself is rated for industrial temperature (–40°C to +85°C), but Microchip offers AEC-Q100 qualified variants within the same 24XX01 family (e.g., 24AA01-I/P). For automotive use, specify the -I suffix part number to ensure qualification to AEC-Q100 Grade 3 stress testing-covering thermal cycling, humidity, and vibration requirements essential for under-hood or cabin modules.

What is the page write capability of the 24AA01/P?

The 24AA01/P supports an 8-byte page write buffer, allowing up to eight consecutive bytes to be written in a single I²C transaction with one Stop condition. This reduces total write time versus individual byte writes and minimizes bus occupancy. Page boundaries align every 8 bytes (00h–07h, 08h–0Fh, etc.), and crossing boundaries causes wraparound-so software must manage address alignment.