Microchip Technology 24LC32A-I/SN

Overview

24LC32A-I/SN from Microchip Technology is a 32-Kbit I²C serial EEPROM organized as 4K × 8-bit, operating from 2.5V to 5.5V with industrial temperature range (–40°C to +85°C) and 400 kHz maximum clock frequency. It features hardware write-protection via the WP pin, 32-byte page write buffer, and Schmitt-trigger inputs for noise immunity - deployed in embedded system configuration storage, sensor calibration data retention, and power-fail-safe parameter backup.

For engineers reviewing the 24LC32A-I/SN datasheet, 24LC32A-I/SN pinout, 24LC32A-I/SN application, or 24LC32A-I/SN equivalent, key selection criteria include VCC min/max compliance, I²C timing at target clock rate, page write endurance (1M cycles), data retention (>200 years), and SOIC-8 package compatibility with legacy PCB footprints.

Technical Context

The 24LC32A-I/SN implements a two-wire I²C interface with open-drain SDA/SCL pins, requiring external pull-ups. Its internal address pointer supports current-address, random, and sequential read modes, while page write logic enforces 32-byte boundaries aligned to addresses divisible by 32 (0x000–0x01F, etc.). Write protection is sampled only at the Stop bit of each command.

It uses CMOS EEPROM technology with on-chip charge pump for erase/write operations, self-timed write cycles (≤5 ms), and ESD protection >4 kV. The device does not generate ACK during internal write cycles - acknowledge polling is required to detect completion before initiating subsequent commands.

Key Specifications

Pinout & Package

24LC32A-I/SN is supplied in 8-lead SOIC (SN) package: 3.90 mm body width, 1.27 mm pitch, gull-wing leads. Pin 1 is marked with notch or beveled corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C32D-SSHM-T and BR24G32FJ-3GE2, the 24LC32A-I/SN offers optimal balance of industrial temperature rating, proven 32-byte page efficiency, and cost-effective SOIC-8 packaging - making it ideal for high-volume embedded systems where voltage stays ≥2.5V and ECC is not mandated.

Availability

24LC32A-I/SN is available at Aetrix Electronics and suitable for industrial PLC configuration storage, medical device calibration data retention, and automotive body control module parameter backup requiring stable component supply across extended production lifecycles.

Supply support for 24LC32A-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 nonvolatile memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC32A belongs to Microchip's serial EEPROM product line, designed specifically for reliable, low-power, I²C-based configuration and calibration data storage in industrial, automotive, and medical applications.

FAQ

What is the minimum VCC voltage required for reliable operation of the 24LC32A-I/SN?

The 24LC32A-I/SN requires a minimum VCC of 2.5V for full specification compliance, including 400 kHz I²C operation and guaranteed write functionality. Operation below 2.5V is not supported - unlike the 24AA32A variant, which operates down to 1.7V. Using 24LC32A-I/SN at 2.4V may result in failed writes or timing violations per Table 1-2.

How does the WP pin function on the 24LC32A-I/SN, and when is it sampled?

The WP (Write-Protect) pin on the 24LC32A-I/SN is sampled only at the Stop bit of each write command. When tied to VCC, all write operations (byte and page) are inhibited while reads remain fully functional. Toggling WP during an active write cycle has no effect - protection state is latched at the Stop condition, ensuring deterministic behavior during power transitions.

Can the 24LC32A-I/SN perform sequential reads across multiple pages without host intervention?

No - the 24LC32A-I/SN supports sequential reads only within the 4K address space, with automatic rollover from address 0xFFF to 0x000. However, it does not support cross-page sequential reads that span physical page boundaries (e.g., reading from 0x01F to 0x020). Host firmware must manage page boundaries explicitly during large-block reads to avoid unintended data repetition.

What is the maximum number of 24LC32A-I/SN devices that can share the same I²C bus, and how is addressing managed?

Up to eight 24LC32A-I/SN devices can share one I²C bus using hardwired A2/A1/A0 pins to set unique 3-bit chip addresses (0x50–0x57). Each device responds only when its A2/A1/A0 combination matches the corresponding bits in the master's control byte. The SOT-23 variant lacks these pins and defaults to address 0x50, limiting multi-device use in that package.

Is the 24LC32A-I/SN AEC-Q100 qualified, and what grade does it meet?

Yes - the 24LC32A-I/SN is AEC-Q100 qualified for automotive applications. Per the device selection table and datasheet notes, it meets Grade 3 (–40°C to +85°C), making it suitable for body electronics, infotainment, and other non-engine-compartment automotive systems requiring validated reliability.