Microchip Technology 24LC32AFT-I/OT

Overview

24LC32AFT-I/OT from Microchip Technology Inc. is a 32 Kbit I²C-compatible serial EEPROM organized as 4K × 8-bit memory, operating from 2.5V to 5.5V with industrial temperature range (–40°C to +85°C), 400 kHz max clock, and hardware write-protect for upper 1/4 array (C00h–FFFh). It supports page writes up to 32 bytes and delivers <400 μA read current and <1 μA standby current.

For engineers reviewing the 24LC32AFT-I/OT datasheet, 24LC32AFT-I/OT pinout, 24LC32AFT-I/OT application, or 24LC32AFT-I/OT equivalent, this device serves as a low-power, cascaded I²C memory solution for embedded system configuration storage, sensor calibration data retention, and firmware parameter backup in space-constrained industrial control modules.

Technical Context

The 24LC32AFT-I/OT implements a 2-wire I²C slave interface with Schmitt-trigger inputs and slope-controlled outputs to suppress noise and eliminate ground bounce. Its internal address counter enables current-address, random, and sequential read modes, while the 32-byte page buffer supports efficient burst writes without host-side timing overhead.

Write protection is implemented via the WP pin, which-when tied high-blocks writes only to addresses C00h–FFFh (16 Kbits), leaving lower 16 Kbits fully writable. The device uses on-chip charge-pump HV generation for EEPROM programming and features self-timed erase/write cycles with no external timing components required.

Key Specifications

Pinout & Package

24LC32AFT-I/OT is supplied in SOT-23-5 package (5-lead surface-mount), with lead finish Pb-free and RoHS compliant. Pin 1 = WP, Pin 2 = VCC, Pin 3 = SCL, Pin 4 = VSS, Pin 5 = SDA.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC32AFT-I/OT, 24LC32AT-I/OT offers identical functionality with packaging variation, while AT24C32D-SSHM-T trades SOT-23 compactness and hardware write-protection for faster write speed and broader VCC range - making it unsuitable for space-constrained or safety-critical designs requiring physical WP enforcement.

Availability

24LC32AFT-I/OT is available at Aetrix Electronics and suitable for industrial sensor nodes, medical device calibration storage, and smart energy metering systems requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for 24LC32AFT-I/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 leading provider of microcontrollers, analog devices, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC32A series belongs to Microchip's serial EEPROM product line, designed specifically for low-power, I²C-based nonvolatile data storage in space-constrained industrial, automotive, and medical applications requiring high reliability and extended data retention.

FAQ

What is the maximum clock frequency supported by the 24LC32AFT-I/OT?

The 24LC32AFT-I/OT supports a maximum I²C clock frequency of 400 kHz when operated within its specified VCC range of 2.5V to 5.5V. This fast-mode capability enables efficient data transfer for configuration updates and logging tasks without compromising bus timing margins in noise-prone environments.

Does the 24LC32AFT-I/OT have hardware write protection, and how does it work?

Yes, the 24LC32AFT-I/OT includes a dedicated Write-Protect (WP) pin that, when tied to VCC, inhibits write operations to the upper 1/4 of the memory array (addresses C00h–FFFh). Read operations remain fully functional across the entire 32 Kbit space, enabling secure storage of calibration or firmware data while permitting dynamic updates to user-configurable regions.

What package type is used for the 24LC32AFT-I/OT, and what are its key mechanical features?

The 24LC32AFT-I/OT is packaged in a Pb-free, RoHS-compliant SOT-23-5 surface-mount package. It measures 2.9 mm × 1.6 mm × 1.1 mm with a 0.95 mm pitch, offering ultra-compact footprint ideal for dense PCB layouts. The package exposes five terminals: WP, VCC, SCL, VSS, and SDA - with no address pins (A0–A2), resulting in a fixed I²C slave address.

How many write/erase cycles can the 24LC32AFT-I/OT endure, and what is its data retention period?

The 24LC32AFT-I/OT is rated for more than 1 million erase/write cycles and guarantees data retention exceeding 200 years at +85°C ambient temperature. These specifications are validated through accelerated stress testing and ensure long-term reliability in applications such as utility meters and medical devices deployed in unattended environments.

Is the 24LC32AFT-I/OT compatible with standard I²C protocols, and does it support ACK polling?

Yes, the 24LC32AFT-I/OT fully complies with the Philips I²C Bus Specification v2.1 and supports ACK polling to detect write-cycle completion. After issuing a write command and Stop condition, the host can repeatedly send a Start + control byte (R/W = 0) until the device responds with an ACK - eliminating the need for fixed delay timers and optimizing I²C bus utilization.