Microchip Technology 24LC64F-E/MS

Overview

24LC64F-E/MS from Microchip Technology Inc. is a 64 Kbit I²C-compatible serial EEPROM organized as 8K × 8-bit memory, operating from 2.5V to 5.5V with 400 kHz max clock frequency and industrial/automotive temperature range (–40°C to +125°C). It features hardware write-protection for the upper 1/4 array (1800h–1FFFh), 32-byte page write buffer, and Schmitt-trigger inputs for noise immunity - deployed in automotive body control modules, industrial sensor nodes, and embedded system configuration storage.

For engineers reviewing the 24LC64F-E/MS datasheet, 24LC64F-E/MS pinout, 24LC64F-E/MS application, or 24LC64F-E/MS equivalent, key selection criteria include VCC min (2.5V), automotive-grade temp support (–40°C to +125°C), quarter-array write-protect capability, I²C timing compliance at 400 kHz, and MSOP-8 package footprint compatibility.

Technical Context

The 24LC64F-E/MS implements a standard two-wire I²C slave interface with fixed 7-bit device address prefix '1010' and three programmable chip-select bits (A2–A0), enabling up to eight devices on one bus. Its internal address pointer supports current-address, random, and sequential read modes, with automatic rollover from 1FFFh to 0000h during sequential reads.

Write operations use self-timed erase/write cycles with 5 ms typical page write time and acknowledge polling for completion detection. The WP pin samples at the Stop bit to enable/disable write protection for addresses 1800h–1FFFh; SDA/SCL feature Schmitt-trigger inputs (50 ns spike suppression) and slope control to suppress ground bounce.

Key Specifications

Pinout & Package

8-pin MSOP package (3.0 × 3.0 mm body, 0.65 mm lead pitch) with exposed pad option; RoHS-compliant, Pb-free matte tin finish.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C64D-MAHM-T and BR24G64FJ-WE2, the 24LC64F-E/MS uniquely delivers automotive-grade temperature support combined with hardware-enforced quarter-array write protection - enabling safety-critical data isolation in single-chip solutions without external logic.

Availability

24LC64F-E/MS is available at Aetrix Electronics and suitable for automotive body control units, industrial sensor nodes, and medical infusion pumps requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for 24LC64F-E/MS 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 design and manufacturing infrastructure.

The 24LC64F-E/MS belongs to Microchip's 24XX64F family of I²C EEPROMs, engineered specifically for automotive and industrial systems demanding robust nonvolatile storage with hardware-level data integrity controls.

FAQ

What is the minimum VCC voltage required for reliable operation of the 24LC64F-E/MS?

The 24LC64F-E/MS requires a minimum VCC of 2.5V for guaranteed operation across its full automotive temperature range (–40°C to +125°C). Below 2.5V, functionality is not specified - unlike the 24AA64F variant which supports down to 1.7V. This 2.5V floor ensures stable I²C communication and write-cycle completion in 3.3V and 5V automotive subsystems where the 24LC64F-E/MS is commonly deployed.

How does the write-protect feature of the 24LC64F-E/MS function in practice?

The WP pin on the 24LC64F-E/MS enables hardware write-protection for the upper 1/4 memory array (addresses 1800h–1FFFh) when pulled high to VCC. Writes to this region are blocked while reads remain fully functional. The pin is sampled at the Stop bit of each write command, so toggling WP mid-operation has no effect. This allows safe storage of immutable calibration data or firmware signatures without software intervention - a key requirement in ISO 26262-compliant automotive designs using the 24LC64F-E/MS.

Can multiple 24LC64F-E/MS devices share the same I²C bus, and how is addressing managed?

Yes, up to eight 24LC64F-E/MS devices can operate on a single I²C bus using the A0, A1, and A2 address pins. These three pins form the LSBs of the 7-bit slave address (prefix '1010'), allowing unique addresses from 1010000 to 1010111. Each device must have a distinct A2:A1:A0 combination - typically hardwired to VSS or VCC. The 24LC64F-E/MS does not support address pin omission (unlike SOT-23 variants), making explicit pin configuration mandatory for multi-device configurations.

What is the typical write cycle time for page writes on the 24LC64F-E/MS?

The 24LC64F-E/MS has a typical page write cycle time of 5 ms, applicable to both single-byte and up to 32-byte page writes. This self-timed duration begins after the master issues the Stop condition and is independent of VCC within the 2.5V–5.5V range. During this period, the device does not acknowledge I²C commands - a behavior leveraged by acknowledge polling to detect write completion without fixed delays. This 5 ms value is confirmed in DS22154B, Table 1-2, Parameter TWC.

Is the 24LC64F-E/MS qualified for automotive applications, and what evidence supports this?

Yes, the 24LC64F-E/MS is explicitly qualified for automotive use, indicated by the 'E' suffix denoting the extended temperature grade (–40°C to +125°C) and documented in Microchip's DS22154B datasheet. Electrical specifications, including DC characteristics, AC timing, and endurance, are guaranteed across this full range. While AEC-Q100 test reports are not included in the public datasheet, Microchip lists the 24LC64F-E/MS in its automotive-qualified product portfolio, and the 'E' grade designation aligns with AEC-Q100 Grade 1 requirements for passive components used in automotive electronics.