Microchip Technology 24FC04HT-E/OT

Overview

24FC04HT-E/OT from Microchip Technology Inc. is a 4-Kbit I²C-compatible serial EEPROM organized as two 256 × 8-bit blocks, supporting 1.7V–5.5V operation, 1 MHz clock frequency (at full V_CC), and extended temperature range (–40°C to +125°C). It features hardware write-protection for half-array (100h–1FFh), 16-byte page write buffer, and <1 µA standby current - deployed in automotive body control modules requiring nonvolatile parameter storage under wide thermal and supply-voltage variation.

For engineers reviewing the 24FC04HT-E/OT datasheet, 24FC04HT-E/OT pinout, 24FC04HT-E/OT application, or 24FC04HT-E/OT equivalent, this page delivers verified electrical specs, package mapping to SOT-23-5, I²C timing constraints at 1.7V–5.5V, endurance (1M cycles), and design-meaningful feature translation - all confirmed against Microchip DS20002119C.

Technical Context

The 24FC04HT-E/OT 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 supports current-address, random, and sequential read modes, while the 16-byte page buffer enables efficient burst writes without host-side buffering.

Write protection is implemented via the WP pin: tied to V_CC, it disables writes to addresses 100h–1FFh (half-array); tied to V_SS, full-array access is enabled. Acknowledge polling is supported to detect write-cycle completion without fixed delays - critical for deterministic real-time firmware.

Key Specifications

Pinout & Package

24FC04HT-E/OT uses the 5-lead SOT-23 package (JEDEC MO-178AA), with 1.6 mm × 2.9 mm footprint and 1.1 mm max height. Pin 1 is SCL; pin 2 is V_SS; pin 3 is SDA; pin 4 is WP; pin 5 is V_CC. No internal connection to A0/A1/A2 - these pins are omitted in SOT-23 variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24FC04HT-E/OT, the 24AA04HT-I/OT trades speed and temperature for lower cost, while the AT24C04-SSHM-T offers comparable speed but replaces hardware WP with command-based control - impacting safety-critical write-lock reliability.

Availability

24FC04HT-E/OT is available at Aetrix Electronics and suitable for automotive ECUs, industrial sensor nodes, and medical device calibration storage requiring stable component supply across extended temperature and voltage ranges.

Supply support for 24FC04HT-E/OT 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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory solutions, with emphasis on embedded control and automotive-grade reliability.

The 24FC04H family was designed for robust, low-power nonvolatile storage in space-constrained, thermally demanding environments - targeting AEC-Q100-compliant automotive subsystems and industrial edge nodes.

FAQ

What is the maximum I²C clock frequency supported by the 24FC04HT-E/OT?

The 24FC04HT-E/OT supports up to 1 MHz I²C clock frequency across its full 1.7V–5.5V supply range, as specified in Table 1-2 of DS20002119C. This is higher than the 400 kHz limit of the 24AA04H and 24LC04BH variants, enabling faster configuration writes in time-critical applications. The 24FC04HT-E/OT maintains this speed even at minimum V_CC = 1.7V, unlike the 24AA04H which drops to 100 kHz below 2.5V.

How does the hardware write-protect (WP) pin function on the 24FC04HT-E/OT?

On the 24FC04HT-E/OT, the WP pin is a dedicated hardware input: when tied to V_CC, writes to memory addresses 100h–1FFh (upper 2 Kbit) are inhibited while reads remain fully functional; when tied to V_SS, full-array read/write access is enabled. This physical lockout prevents firmware bugs or malicious commands from overwriting calibrated parameters - a key requirement in automotive and medical designs.

Is the 24FC04HT-E/OT pin-compatible with other 24XX04H family members in SOT-23 packaging?

Yes - the 24FC04HT-E/OT shares identical 5-pin SOT-23 pinout (SCL, V_SS, SDA, WP, V_CC) and footprint with 24AA04HT-I/OT and 24LC04BHT-E/OT. However, due to differences in maximum clock frequency, temperature rating, and write-protect behavior, direct substitution requires validation of timing margins and environmental operating points in the target application.

What is the endurance specification for the 24FC04HT-E/OT, and how is it tested?

The 24FC04HT-E/OT guarantees 1,000,000 erase/write cycles per memory location, measured at 25°C and V_CC = 5.5V in page mode (DS20002119C, Table 1-2, Parameter D18). This endurance is ensured by characterization - not 100% production tested - and reflects worst-case cycling across the entire memory array under specified voltage/temperature conditions.

Does the 24FC04HT-E/OT require external pull-up resistors on the I²C bus lines?

Yes - the 24FC04HT-E/OT has open-drain SDA and SCL pins, mandating external pull-up resistors to V_CC. For 1 MHz operation, Microchip recommends 2 kΩ pull-ups (DS20002119C, Section 2.2); for lower speeds (e.g., 100 kHz), 10 kΩ is typical. Incorrect pull-up values cause timing violations or bus lockup, especially under capacitive loads exceeding 400 pF.