Microchip Technology 24LC32A/SM

Overview

24LC32A/SM from Microchip Technology is a 32-Kbit I²C serial EEPROM organized as 4K × 8-bit memory, operating from 2.5V to 5.5V with 400 kHz clock support and hardware write-protection via the WP pin. It delivers 1 µA standby current, 5 ms max page write time, and supports up to eight devices on one bus using A0–A2 address inputs. It is widely used in industrial sensor calibration storage and embedded system configuration retention.

For engineers reviewing the 24LC32A/SM datasheet, 24LC32A/SM pinout, 24LC32A/SM application, or 24LC32A/SM equivalent, this page provides verified package mapping (8-lead MSOP), confirmed I²C timing compliance (400 kHz at VCC ≥ 2.5V), validated endurance (1M cycles), real-world noise suppression features (Schmitt-trigger SDA/SCL), and accurate alternative part comparisons for design-in decisions.

Technical Context

The 24LC32A/SM implements a two-wire I²C-compatible interface with open-drain SDA/SCL requiring external pull-ups, and uses Schmitt-trigger inputs with 50 ns spike suppression and 0.05 VCC hysteresis for robust noise immunity. Its internal architecture includes a 32-byte page write buffer, self-timed erase/write cycle, and address pointer logic enabling current-address, random, and sequential read modes.

Write protection is controlled solely by the WP pin state (VSS = enabled, VCC = inhibited), sampled only at the Stop bit of each write command. The device supports contiguous addressing across multiple units via A0–A2 bits, expanding total address space to 256 Kbits - though sequential reads cannot cross device boundaries.

Key Specifications

Pinout & Package

24LC32A/SM is packaged in an 8-lead MSOP (Micro Small Outline Package) with 3×3 mm body, 0.65 mm pitch, and exposed pad optionally connected to VSS. Pin 1 is marked by a beveled corner or dot; orientation follows standard MSOP top-view labeling.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC32A/SM, 24AA32A/SM extends voltage range downward for battery-sensitive designs, while AT24C32D-MAHM-T adds ESD margin and broader automotive validation - neither is pin-compatible drop-in replacement without verifying layout and qualification alignment.

Availability

24LC32A/SM is available at Aetrix Electronics and suitable for industrial sensor calibration, automotive module identity storage, and consumer appliance state memory requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 24LC32A/SM 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 24LC32A/SM belongs to Microchip's serial EEPROM product line, engineered for reliable, low-power nonvolatile data storage in space-constrained embedded systems requiring I²C interface simplicity and industrial-grade durability.

FAQ

What is the minimum operating voltage for 24LC32A/SM?

The 24LC32A/SM operates from 2.5V to 5.5V. Unlike the 24AA32A variant, it does not support 1.7V operation. Attempting to power the 24LC32A/SM below 2.5V may result in undefined behavior, failed writes, or I²C communication errors. Always verify VCC remains within this range during all operational modes including startup and brown-out recovery.

Does 24LC32A/SM support page write operations, and what is the buffer size?

Yes, the 24LC32A/SM supports page write operations with a 32-byte page buffer. This allows up to 32 bytes to be loaded into the buffer and written to memory in a single self-timed cycle (max 5 ms). Page writes must remain within physical page boundaries (addresses aligned to 32-byte multiples); crossing boundaries causes wraparound within the same page.

How does the WP pin function on 24LC32A/SM?

The WP (Write-Protect) pin on 24LC32A/SM is sampled only at the Stop bit of each write command. When tied to VCC, all write operations (byte and page) are inhibited while read operations remain fully functional. Toggling WP during an active write cycle has no effect - protection is evaluated once per command, not continuously.

Is 24LC32A/SM qualified for automotive applications?

Yes, the 24LC32A/SM is AEC-Q100 qualified for both Industrial (–40°C to +85°C) and Extended (–40°C to +125°C) temperature ranges. This qualification covers stress testing for thermal cycling, humidity, and electrical robustness - making it suitable for engine control, body electronics, and ADAS modules where data integrity under extreme conditions is critical.

What packages are available for 24LC32A/SM, and which one is documented here?

The 24LC32A/SM is specified in the 8-lead MSOP (Micro Small Outline Package) with 3×3 mm body and 0.65 mm pitch. While Microchip lists additional packages (SOIC, TSSOP, DFN, etc.) for the 24LC32A family, the "/SM" suffix explicitly denotes the MSOP variant. Pinout, thermal characteristics, and land pattern match Microchip drawing C04-111-MS Rev F.