Microchip Technology 24LC01B-E/MS

Overview

24LC01B-E/MS from Microchip Technology Inc. is a 1 Kbit I²C-compatible serial EEPROM organized as 128 × 8-bit memory with hardware write-protection, 8-byte page buffer, and operation from 2.5V to 5.5V. It supports 400 kHz clock frequency, delivers ≤1 mA read current and ≤5 µA extended-temperature standby current, and is rated for >1 million erase/write cycles and >200 years data retention. It serves in industrial sensor calibration storage and embedded system configuration backup.

For engineers reviewing the 24LC01B-E/MS datasheet, 24LC01B-E/MS pinout, 24LC01B-E/MS application, or 24LC01B-E/MS equivalent, key selection considerations include its 2.5V minimum VCC, E-temp (–40°C to +125°C) rating, MSOP-8 package compatibility, I²C bus timing compliance at 400 kHz, and hardware WP pin functionality for full-array write protection.

Technical Context

The 24LC01B-E/MS 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 an 8-byte page latch, address pointer, and HV generator for EEPROM programming, enabling self-timed byte and page writes.

It operates exclusively as a slave device on the I²C bus, responding to control code '1010' followed by three don't-care bits and R/W bit. Addressing uses only A6–A0; A0–A2 pins are unconnected and may be left floating or tied to VSS/VCC without functional impact.

Key Specifications

Pinout & Package

24LC01B-E/MS is supplied in an 8-lead MSOP package (Microchip drawing C04-061-MS). Pin 1 is A0 (NC), Pin 2 is A1 (NC), Pin 3 is A2 (NC), Pin 4 is VSS (ground), Pin 5 is SDA (bidirectional open-drain I/O requiring external pull-up), Pin 6 is SCL (input clock), Pin 7 is WP (active-high write-protect), and Pin 8 is VCC (power supply).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA01-I/MS and 24FC01-I/MS, the 24LC01B-E/MS uniquely balances extended-temperature capability, hardware write-protection, and 2.5V+ supply compatibility-making it optimal for automotive and industrial applications where thermal resilience and data integrity are prioritized over ultra-low voltage or maximum speed.

Availability

24LC01B-E/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, automotive body control modules, medical diagnostic settings, and smart energy meter firmware patch storage requiring stable component supply across extended temperature ranges.

Supply support for 24LC01B-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 microcontrollers, analog devices, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC01B belongs to Microchip's legacy 24XX01 family of I²C serial EEPROMs, designed specifically for cost-sensitive, space-constrained embedded systems requiring reliable nonvolatile storage with minimal external components.

FAQ

What is the minimum supply voltage required for reliable operation of the 24LC01B-E/MS?

The 24LC01B-E/MS requires a minimum VCC of 2.5V for guaranteed operation across its full extended temperature range (–40°C to +125°C). Operation below 2.5V is not specified and may result in failed writes, corrupted reads, or loss of I²C communication - unlike the 24AA01 (1.7V min) or 24FC01 (1.7V min), the 24LC01B-E/MS is not rated for sub-2.5V systems.

Can the A0, A1, and A2 pins of the 24LC01B-E/MS be used to configure I²C slave addressing?

No - the A0, A1, and A2 pins of the 24LC01B-E/MS are internally unconnected (NC) and have no effect on I²C addressing. The device responds exclusively to the fixed 7-bit client address 1010xxx (where xxx are don't-care bits), meaning only one 24LC01B-E/MS can reside on a given I²C bus segment without address conflict. This differs from higher-density Microchip EEPROMs (e.g., 24LC256) that use these pins for address expansion.

How does the Write-Protect (WP) pin function on the 24LC01B-E/MS, and what happens when it is left unconnected?

When WP is tied to VCC, all write operations (byte and page) to the 24LC01B-E/MS memory array (addresses 00h–7Fh) are inhibited; reads remain fully functional. When tied to VSS, normal read/write operation is enabled. If left unconnected, WP floats near VCC due to internal biasing, resulting in default write-protection - so intentional writes require explicit VSS connection. This behavior is documented in Microchip DS20001711M, Section 2.4.

What is the maximum supported I²C clock frequency for the 24LC01B-E/MS, and does it vary with supply voltage?

The 24LC01B-E/MS supports a maximum I²C clock frequency of 400 kHz when VCC is between 2.5V and 5.5V. Unlike the 24AA01 (which drops to 100 kHz below 2.5V) or 24FC01 (1 MHz capable), the 24LC01B-E/MS has no lower-frequency fallback mode - operation outside 400 kHz violates AC timing specifications and risks data corruption or bus lockup.

Is the 24LC01B-E/MS qualified for automotive applications, and what evidence supports this claim?

Yes - the 24LC01B-E/MS carries AEC-Q100 qualification per Microchip's DS20001711M datasheet (page 1). Its Extended temperature grade (–40°C to +125°C), 2.5V–5.5V VCC range, and tested ESD immunity (>4 kV HBM) meet automotive subsystem requirements. The "E" in the part number explicitly denotes Extended temp grade, and the "-E/MS" suffix confirms packaging and screening for automotive-qualified MSOP-8 delivery.