Microchip Technology 24LC32AT-I/MS

Overview

24LC32AT-I/MS 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 housed in an 8-lead MSOP package. It supports 400 kHz clock frequency, features hardware write-protection via WP pin, and delivers 1 µA standby current and 5 ms max page write time - used for nonvolatile configuration storage in embedded controllers and sensor modules.

For engineers reviewing the 24LC32AT-I/MS datasheet, 24LC32AT-I/MS pinout, 24LC32AT-I/MS application, or 24LC32AT-I/MS equivalent, key selection considerations include VCC compatibility (2.5–5.5V), I²C timing compliance at 400 kHz, MSOP package footprint constraints, and hardware write-protect implementation using the WP terminal.

Technical Context

The 24LC32AT-I/MS implements a two-wire I²C interface with Schmitt-trigger inputs on SDA/SCL for noise immunity and slope-controlled outputs to suppress ground bounce. Its internal architecture includes a 32-byte page write buffer, address pointer logic for sequential reads, and a self-timed erase/write cycle controlled by internal high-voltage generation.

It uses three chip-address pins (A0–A2) to support up to eight devices on one bus, with device addressing based on the 4-bit control code '1010' followed by A2:A0 and R/W bit. The WP pin samples at the Stop condition to enable/disable writes, and acknowledge polling is required to detect write completion.

Key Specifications

Pinout & Package

8-Lead MSOP (Micro Small Outline Package), 3 mm × 3 mm body, 0.65 mm pitch, exposed pad optional (not electrically connected).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC32AT-I/MS, the 24AA32AT-I/MS extends voltage range downward but maintains identical timing and packaging, while the AT24C32D-MAHM-T omits WP yet offers comparable density and speed - making it suitable only where hardware-level write security is not mandated.

Availability

24LC32AT-I/MS is available at Aetrix Electronics and suitable for industrial sensor calibration, embedded controller configuration, and medical device settings backup requiring stable component supply across extended product lifecycles.

Supply support for 24LC32AT-I/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 U.S.-based semiconductor manufacturer specializing in microcontrollers, analog devices, and nonvolatile memory solutions for industrial, automotive, and consumer markets.

The 24LC32AT-I/MS belongs to Microchip's 24XX32A family of I²C EEPROMs, designed specifically for reliable, low-power configuration storage in space-constrained embedded systems with stringent longevity requirements.

FAQ

What is the minimum supply voltage required for reliable operation of the 24LC32AT-I/MS?

The 24LC32AT-I/MS requires a minimum VCC of 2.5V for guaranteed operation across its full industrial temperature range (–40°C to +85°C). Below 2.5V, timing parameters degrade and write functionality may fail. This distinguishes it from the 24AA32A variant, which supports down to 1.7V. Always verify VCC stability under load using the 24LC32AT-I/MS DC characteristics table.

How does the WP pin function on the 24LC32AT-I/MS during a write transaction?

The WP pin on the 24LC32AT-I/MS is sampled at the Stop condition of each write command. When tied to VCC, it inhibits all write operations (byte or page) while allowing unrestricted reads. If WP is pulled high mid-write, the ongoing cycle completes normally - protection only applies to new commands. This behavior is confirmed in Section 6.3 of the 24LC32AT-I/MS datasheet.

Can the 24LC32AT-I/MS perform sequential reads across multiple pages?

No. The 24LC32AT-I/MS supports sequential reads only within the same 4K address space, but not across physical page boundaries (0x000–0x01F, etc.). Attempting a page-crossing sequential read causes the internal address pointer to roll over to the start of the current page. Software must manage page boundaries explicitly - a constraint documented in Section 6.2 of the 24LC32AT-I/MS datasheet.

What is the maximum number of 24LC32AT-I/MS devices that can share a single I²C bus?

Up to eight 24LC32AT-I/MS devices can coexist on one I²C bus using unique combinations of A0, A1, and A2 address pins. Each pin must be hardwired to VSS or VCC to generate a distinct 3-bit chip address. The base I²C client address is 0xA0 (1010b), with A2:A0 forming bits 6–4 - fully detailed in Section 5.0 of the 24LC32AT-I/MS datasheet.

Is the 24LC32AT-I/MS RoHS compliant and qualified for automotive use?

Yes, the 24LC32AT-I/MS is RoHS compliant per Microchip's DS20001713P documentation. However, it is not AEC-Q100 qualified - only the 24LC32A (without the 'T' suffix) carries automotive qualification. The 'T' in 24LC32AT-I/MS denotes tape-and-reel packaging, not automotive grade. For automotive applications, specify 24LC32A-I/MS or confirm qualification status directly with Microchip.