Microchip Technology 24LC04B-I/P

Overview

24LC04B-I/P from Microchip Technology Inc. is a 4-Kbit I²C-compatible serial EEPROM organized as two 256 × 8-bit blocks, operating from 2.5V 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 features hardware write-protection via the WP pin and supports up to 1 million erase/write cycles for embedded system configuration storage.

For engineers reviewing the 24LC04B-I/P datasheet, 24LC04B-I/P pinout, 24LC04B-I/P application, or 24LC04B-I/P equivalent, this device serves as a low-power, noise-immune nonvolatile memory solution for microcontroller-based systems requiring reliable parameter retention, calibration data storage, and firmware configuration in space-constrained designs.

Technical Context

The 24LC04B-I/P implements a two-wire I²C interface with Schmitt-trigger inputs and slope-controlled outputs to suppress ground bounce and bus noise. Its internal address pointer enables current-address, random, and sequential read modes, while the 16-byte page buffer allows efficient burst writes within physical page boundaries (0–15, 16–31, etc.).

Write protection is implemented via a dedicated WP pin tied to VCC to inhibit all write operations across the full 000–1FFh address space; no internal address bits (A0–A2) are connected, simplifying PCB routing. Acknowledge polling is supported to detect write cycle completion without fixed delay timing.

Key Specifications

Pinout & Package

24LC04B-I/P is supplied in an 8-lead PDIP (Plastic Dual In-Line Package) with 300 mil body width. Pin 1 is marked by a notch or dot; orientation follows standard DIP top-view convention.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA04-I/P and AT24C04-PU, the 24LC04B-I/P offers optimal balance of industrial temperature support, proven AEC-Q100 qualification, and strict 2.5V minimum supply - making it preferred for cost-sensitive, thermally stable 3.3V/5V embedded systems where ultra-low voltage operation is unnecessary.

Availability

24LC04B-I/P is available at Aetrix Electronics and suitable for industrial sensor calibration, consumer appliance settings, medical device configuration, and automotive body control module applications requiring stable component supply and long-term manufacturing continuity.

Supply support for 24LC04B-I/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 components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC04B belongs to Microchip's 24XX04 family of I²C serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in resource-constrained embedded systems across industrial, automotive, and consumer markets.

FAQ

What is the maximum clock frequency supported by the 24LC04B-I/P?

The 24LC04B-I/P supports a maximum I²C clock frequency of 400 kHz when operated within its specified V_CC range of 2.5V to 5.5V. This aligns with standard-mode I²C timing requirements and ensures robust communication in electrically noisy environments. The 24LC04B-I/P does not support fast-mode (1 MHz) operation - that capability is reserved for the 24FC04 variant. Always verify timing margins using the AC characteristics table in the DS20001708P datasheet for your specific V_CC and temperature conditions.

Does the 24LC04B-I/P require external pull-up resistors on SDA and SCL lines?

Yes, the 24LC04B-I/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 - selected based on bus capacitance and rise-time requirements. The 24LC04B-I/P itself contains no internal pull-ups; omitting external resistors will prevent proper bus signaling and cause communication failure. Refer to Figure 4-1 and Section 2.2 of the DS20001708P datasheet for implementation guidance.

How does hardware write-protection work on the 24LC04B-I/P?

Hardware write-protection on the 24LC04B-I/P is controlled by the WP (Write-Protect) pin: when tied to VCC, the entire memory array (addresses 000h–1FFh) becomes read-only; when tied to VSS, full read/write access is enabled. This is a physical, non-volatile lock - no register programming or command sequence is involved. The 24LC04B-I/P does not support partial-page or software-based write protection. For secure deployment, tie WP to VCC via a solder jumper or configurable header to prevent accidental or malicious firmware writes.

What is the page write capability of the 24LC04B-I/P?

The 24LC04B-I/P features a 16-byte page write buffer, allowing up to 16 bytes to be written in a single I²C transaction after issuing one Start condition and before the final Stop condition. Writes must remain within a single physical page boundary (e.g., addresses 0–15, 16–31); crossing boundaries causes wraparound within the current page. Each page write completes in ≤5 ms. This capability significantly improves write efficiency versus byte-by-byte writes - especially for storing contiguous configuration blocks - and is fully supported in the 24LC04B-I/P's I²C protocol implementation per Section 6.2 of DS20001708P.

Is the 24LC04B-I/P qualified for automotive applications?

Yes, the 24LC04B-I/P is AEC-Q100 qualified for automotive applications, specifically meeting Grade 3 (–40°C to +85°C) requirements. This qualification covers stress testing for temperature cycling, humidity bias, ESD (>4 kV HBM), and other reliability parameters defined in the AEC-Q100 standard. While the "I" suffix denotes Industrial temperature grade, the AEC-Q100 qualification confirms suitability for under-hood and cabin electronics where thermal and electrical robustness are critical. Always confirm compliance with your vehicle program's specific AEC-Q100 revision and test plan requirements.