Microchip Technology 24AA04/P

Overview

24AA04/P from Microchip Technology Inc. is a 4-Kbit I²C-compatible serial EEPROM organized as two 256 × 8-bit blocks, operating from 1.7V to 5.5V with 400 kHz max clock frequency, 1 µA standby current, and industrial temperature range (–40°C to +85°C). It features hardware write-protection via the WP pin, 16-byte page write buffer, and Schmitt-trigger inputs for noise immunity-used in embedded system configuration storage and sensor calibration data retention.

For engineers reviewing the 24AA04/P datasheet, 24AA04/P pinout, 24AA04/P application, or 24AA04/P equivalent, key selection considerations include its 1.7V low-voltage operation, I²C bus compatibility up to 400 kHz, hardware write-protect functionality, 5 ms max page write time, and PDIP-8 packaging for through-hole prototyping and legacy industrial control boards.

Technical Context

The 24AA04/P implements a two-wire I²C interface with fixed 4-bit device code '1010', block-select addressing (B0 bit), and R/W bit control. Its internal architecture includes an EEPROM array, page latches, X/Y decoders, sense amplifiers, and HV generator for programming-enabling byte and page writes without external high-voltage supply.

It supports three read modes: current address, random, and sequential-each relying on an internally incremented Address Pointer. Acknowledge polling is used to detect write cycle completion, and SCL/SDA inputs incorporate Schmitt triggers and spike filters (50 ns) to ensure robust operation on electrically noisy buses.

Key Specifications

Pinout & Package

24AA04/P is supplied in an 8-lead plastic dual in-line package (PDIP), 300 mil body width, with through-hole mounting. Pin 1 is top-left corner when notch faces upward.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC04B/P and AT24C04-PU, the 24AA04/P uniquely supports 1.7V operation and carries AEC-Q100 qualification - making it the only option for battery-backed 1.8V systems requiring automotive-grade reliability and extended voltage margin.

Availability

24AA04/P is available at Aetrix Electronics and suitable for industrial PLC configuration storage, medical device calibration data retention, and automotive body control module settings requiring stable component supply across multi-year production cycles.

Supply support for 24AA04/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 microcontrollers, analog devices, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA04/P belongs to Microchip's 24XX04 family of I²C serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in space-constrained embedded systems across industrial, medical, and automotive markets.

FAQ

What is the minimum operating voltage for the 24AA04/P?

The 24AA04/P operates down to 1.7V, enabling direct interface with 1.8V logic families and battery-powered systems. This is lower than the 2.5V minimum required by the 24LC04B/P variant. The 24AA04/P maintains full 400 kHz I²C functionality above 2.5V and de-rates to 100 kHz between 1.7V and 2.5V - a key differentiator for ultra-low-power designs.

Does the 24AA04/P require external pull-up resistors on SDA and SCL lines?

Yes, the 24AA04/P requires external pull-up resistors on both SDA and SCL lines because its I²C interface uses open-drain outputs. Typical values are 10 kΩ for 100 kHz operation and 2 kΩ for 400 kHz. The exact value depends on bus capacitance and desired rise time; insufficient pull-up strength causes I²C communication failures or timeout errors during 24AA04/P read/write sequences.

How does the WP pin function on the 24AA04/P?

The WP (Write-Protect) pin on the 24AA04/P is an active-high input that disables all write operations when tied to VCC. When grounded (VSS), full read/write access is enabled. Unlike software-based protection, this hardware lock prevents accidental or malicious writes even during MCU firmware faults - a critical safety feature in systems storing calibration data or configuration parameters for the 24AA04/P.

What is the maximum page write size supported by the 24AA04/P?

The 24AA04/P supports a 16-byte page write buffer, allowing up to 16 bytes to be written in a single I²C transaction. This reduces bus traffic and host processor overhead compared to byte-wise writes. However, page boundaries are fixed at 16-byte intervals (addresses 0x00–0x0F, 0x10–0x1F, etc.), and crossing a boundary causes wraparound - so proper address alignment is required to avoid unintended overwrites in the 24AA04/P's memory array.

Is the 24AA04/P qualified for automotive applications?

Yes, the 24AA04/P is AEC-Q100 qualified for automotive applications, meeting stress test requirements for temperature cycling, humidity, and ESD. This qualification applies specifically to the 24AA04 variant (not 24LC04B or 24FC04), confirming its suitability for body control modules, infotainment systems, and other automotive ECUs where reliability under harsh conditions is mandatory - a verified attribute of the 24AA04/P part number.