Microchip Technology 24AA04-I/SN

Overview

24AA04-I/SN 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, 5 ms max page write time, and industrial temperature range (–40°C to +85°C). It supports hardware write-protection via the WP pin and is commonly used in embedded system configuration storage, sensor calibration data retention, and power-fail-safe parameter backup.

For engineers reviewing the 24AA04-I/SN datasheet, 24AA04-I/SN pinout, 24AA04-I/SN application, or 24AA04-I/SN equivalent, this page delivers verified electrical specs, SOIC-8 package layout, I²C timing compliance at 1.7V–5.5V, endurance (1M cycles), and data retention (>200 years) - all confirmed for the exact 24AA04-I/SN variant.

Technical Context

The 24AA04-I/SN implements a two-wire I²C interface with Schmitt-trigger inputs and slope-controlled outputs to suppress noise and eliminate ground bounce. Its internal architecture includes a 16-byte page write buffer, self-timed erase/write cycle, and address pointer logic supporting current-address, random, and sequential read modes.

It uses open-drain SDA/SCL with external pull-up resistors (10 kΩ typical at 100 kHz), supports ACK polling to detect write completion, and features dedicated hardware write-protection via the WP pin - tied to VSS for full read/write access or VCC to lock the entire 4-Kbit array.

Key Specifications

Pinout & Package

24AA04-I/SN is supplied in an 8-lead narrow SOIC (SN) package per Microchip drawing C04-057-SN Rev F, with 1.27 mm pitch, 3.90 mm body width, and gull-wing leads. Pin 1 is marked by a beveled corner or notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC04B-I/SN, the 24AA04-I/SN adds 1.7V operation for ultra-low-voltage compatibility; compared with 24FC04-I/SN, it trades 1 MHz speed for broader legacy design support and identical qualification scope.

Availability

24AA04-I/SN is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded system configuration, and power-fail parameter backup requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant packaging.

Supply support for 24AA04-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 components, and memory solutions, headquartered in Chandler, Arizona, with global manufacturing and support infrastructure.

The 24AA04-I/SN belongs to Microchip's 24XX04 family of I²C serial EEPROMs, designed specifically for cost-sensitive, space-constrained applications needing reliable nonvolatile storage with minimal external components and broad voltage compatibility.

FAQ

What is the exact memory organization of the 24AA04-I/SN?

The 24AA04-I/SN contains 4 Kbit of EEPROM memory organized as two independent 256 × 8-bit blocks (000h–0FFh and 100h–1FFh), selectable via the B0 bit in the I²C control byte. Each block supports byte and page (up to 16 bytes) writes, with automatic address incrementing during sequential reads. This structure enables efficient partitioning of configuration and calibration data.

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

Yes, the 24AA04-I/SN requires external pull-up resistors on both SDA and SCL lines because its I²C interface uses open-drain outputs. For 400 kHz operation, a 2 kΩ resistor is recommended; for 100 kHz, 10 kΩ is typical. The exact value depends on bus capacitance and V_CC, but omission will prevent proper I²C communication - a requirement explicitly stated in the 24AA04-I/SN datasheet.

Can the A0, A1, and A2 pins of the 24AA04-I/SN be left unconnected?

Yes, the A0, A1, and A2 pins of the 24AA04-I/SN have no internal connection and may be left floating, tied to VSS, or tied to VCC without affecting functionality. Unlike higher-density EEPROMs, the 24AA04-I/SN uses a fixed I²C slave address (1010xxxR/W) where the "xxx" bits are don't-care - so these pins serve no addressing purpose and pose no risk if unconnected.

How does the WP pin function on the 24AA04-I/SN?

The WP (Write-Protect) pin on the 24AA04-I/SN provides hardware-level memory locking: when tied to VCC, the entire 4-Kbit array (addresses 000h–1FFh) becomes read-only; when tied to VSS, full read/write access is enabled. This feature operates independently of software commands and is active immediately - a key safeguard for critical calibration or security data stored in the 24AA04-I/SN.

What is the maximum write cycle time for the 24AA04-I/SN, and how should firmware handle it?

The 24AA04-I/SN has a maximum write cycle time of 5 ms for both byte and page writes. Firmware must either wait this duration after issuing a Stop condition or use ACK polling - sending repeated Start + control byte (R/W=0) sequences until the device acknowledges. Relying on fixed delays ensures compatibility across all V_CC and temperature conditions specified for the 24AA04-I/SN.