Microchip Technology 24LC32AFT-E/SN

Overview

24LC32AFT-E/SN 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 μA max read current, 1 μA max standby current, and hardware write-protect for upper 1/4 array (C00h–FFFh). It supports cascading up to eight devices on one bus and is used in embedded system configuration storage and sensor calibration data retention.

For engineers reviewing the 24LC32AFT-E/SN datasheet, 24LC32AFT-E/SN pinout, 24LC32AFT-E/SN application, or 24LC32AFT-E/SN equivalent, key selection criteria include VCC min (2.5V), I²C clock compatibility (100/400 kHz), page write buffer size (32 bytes), write-protect granularity (quarter-array), and TSSOP-8 package footprint compatibility with legacy 24LCxx designs.

Technical Context

The 24LC32AFT-E/SN implements a two-wire I²C interface with Schmitt-trigger inputs and slew-rate-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 write buffer allows burst writes within physical page boundaries (0–31, 32–63, etc.).

Write protection is implemented via the WP pin: when tied to VCC, writes to addresses C00h–FFFh are inhibited; reads remain fully functional. The device uses self-timed erase/write cycles (≤5 ms) and supports acknowledge polling to detect write completion without fixed delay timing.

Key Specifications

Pinout & Package

24LC32AFT-E/SN is supplied in an 8-lead TSSOP package (3.0 mm × 4.4 mm, 0.65 mm pitch), RoHS-compliant and Pb-free. Pin 1 is A0 (chip address input), Pin 2 is A1, Pin 3 is A2, Pin 4 is VSS (ground), Pin 5 is SDA (bidirectional open-drain I²C data), Pin 6 is SCL (I²C clock input), Pin 7 is WP (write-protect input), 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 24LC32AFT-E/SN, 24LC32AT-I/SN omits automotive qualification but reduces cost, while AT24C32D-SSHM-T extends voltage range and adds interrupt signaling-making it preferable for mixed-voltage designs where E-temp is not mandatory.

Availability

24LC32AFT-E/SN is available at Aetrix Electronics and suitable for industrial sensor calibration storage, embedded system configuration memory, and automotive body control module settings requiring stable component supply across production lifecycles.

Supply support for 24LC32AFT-E/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 memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC32AFT-E/SN belongs to Microchip's 24LCxx family of I²C serial EEPROMs, designed specifically for reliable, low-power nonvolatile data storage in space-constrained industrial and automotive applications.

FAQ

What is the minimum operating voltage for the 24LC32AFT-E/SN?

The 24LC32AFT-E/SN requires a minimum VCC of 2.5V, as specified in its device selection table and DC characteristics. This distinguishes it from the 24AA32AF variant, which operates down to 1.7V. Operation below 2.5V is not guaranteed and may result in I²C communication failure or incomplete write cycles. Always verify VCC remains within 2.5V–5.5V during all operational modes including standby and active write.

Does the 24LC32AFT-E/SN support page write operations, and what is the maximum buffer size?

Yes, the 24LC32AFT-E/SN supports page write operations with a 32-byte buffer. This allows up to 32 contiguous bytes to be loaded into the on-chip latch and written to memory upon receipt of a Stop condition. Physical page boundaries align to 32-byte intervals (e.g., 0x000–0x01F), and crossing a boundary causes wraparound within the same page - software must enforce alignment to avoid unintended overwrites.

How does the write-protect (WP) pin function on the 24LC32AFT-E/SN?

The WP pin on the 24LC32AFT-E/SN enables hardware write-protection for the upper 1/4 of the memory array (addresses C00h–FFFh). When WP is tied to VCC, writes to that region are inhibited while reads remain fully functional. The pin is sampled at the Stop bit of each write command; toggling WP mid-cycle has no effect. WP must be hard-wired to VSS or VCC - floating is undefined and may cause erratic behavior.

What package type and lead count does the 24LC32AFT-E/SN use?

The 24LC32AFT-E/SN uses an 8-lead TSSOP (Thin Shrink Small Outline Package) with 3.0 mm × 4.4 mm body dimensions and 0.65 mm lead pitch. This surface-mount package is RoHS-compliant and Pb-free, and matches footprint compatibility with industry-standard 24LCxx EEPROMs. Pin 1 is A0, Pin 4 is VSS, Pin 5 is SDA, Pin 6 is SCL, Pin 7 is WP, and Pin 8 is VCC.

Can multiple 24LC32AFT-E/SN devices share the same I²C bus, and how is addressing managed?

Yes, up to eight 24LC32AFT-E/SN devices can share one I²C bus using the A0, A1, and A2 address pins. These three inputs form the three least-significant bits of the 7-bit slave address (base 1010xxx), allowing unique addressing per device. All address pins must be hard-wired to VSS or VCC - dynamic control by a microcontroller is unsupported. The SOT-23 variant lacks these pins and supports only single-device operation.