Microchip Technology 24AA32A-I/SM

Overview

24AA32A-I/SM from Microchip Technology is a 32-Kbit I²C serial EEPROM organized as 4K × 8-bit, operating from 1.7V to 5.5V with 400 kHz max clock frequency, 1 µA standby current, and industrial temperature range (–40°C to +85°C). It features hardware write-protection via the WP pin, 32-byte page write buffer, and Schmitt-trigger inputs for noise immunity-used in embedded system configuration storage, sensor calibration data retention, and firmware parameter backup.

For engineers reviewing the 24AA32A-I/SM datasheet, 24AA32A-I/SM pinout, 24AA32A-I/SM application, or 24AA32A-I/SM equivalent, key selection criteria include low-voltage operation down to 1.7V, I²C bus compatibility at 100/400 kHz, page write timing ≤5 ms, hardware write-protect functionality, and MSOP-8 packaging with verified pin mapping for PCB layout and signal integrity planning.

Technical Context

The 24AA32A-I/SM implements a two-wire I²C-compatible interface with open-drain SDA/SCL pins requiring external pull-ups, and uses address pins A0–A2 to support up to eight devices on a shared bus. Its internal architecture includes a 32-byte page latch, EEPROM array with HV generator, and address pointer logic enabling sequential, random, and current-address read modes.

Write operations are self-timed with internal erase/write cycles; acknowledge polling is supported to detect completion. The WP pin samples at the Stop bit to enable/disable writes, and Schmitt-trigger inputs with 50 ns spike suppression ensure robustness in noisy environments. Page boundaries align to 32-byte offsets, and crossing boundaries causes wraparound-not automatic page advancement.

Key Specifications

Pinout & Package

24AA32A-I/SM is packaged in an 8-lead MSOP (Micro Small Outline Package) with 3×3 mm body, 0.65 mm pitch, and gull-wing leads. Pin 1 is marked by a beveled corner or dot; package conforms to JEDEC MO-187AA.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC32A-I/SM, the 24AA32A-I/SM enables lower-voltage operation critical for battery-powered nodes, while AT24C32D-MAHM-T adds 1 MHz capability but introduces WP logic inversion - making 24AA32A-I/SM optimal for 1.7–1.8V I²C systems requiring drop-in compatibility and proven industrial qualification.

Availability

24AA32A-I/SM is available at Aetrix Electronics and suitable for industrial sensor nodes, medical device calibration storage, and smart energy metering requiring stable component supply, long-term lifecycle assurance, and RoHS-compliant sourcing.

Supply support for 24AA32A-I/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 microcontroller, analog, FPGA, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA32A-I/SM belongs to Microchip's serial EEPROM product line, designed specifically for reliable, low-power, I²C-based nonvolatile data storage in space-constrained embedded systems across industrial, medical, and automotive markets.

FAQ

What is the minimum operating voltage for the 24AA32A-I/SM?

The 24AA32A-I/SM operates down to 1.7V, enabling direct integration with 1.8V microcontrollers and low-power sensor interfaces without level translation. This specification is validated across the full industrial temperature range (–40°C to +85°C) and distinguishes it from the 24LC32A-I/SM, which requires ≥2.5V. At 1.7V, clock frequency is limited to 100 kHz, and page write time remains ≤5 ms.

How does the WP pin function on the 24AA32A-I/SM?

The WP (Write-Protect) pin on the 24AA32A-I/SM is an active-high hardware lock: when tied to VCC, all write operations (byte and page) are inhibited while read operations remain fully functional. The pin is sampled at the Stop bit of each write command, so toggling WP mid-cycle has no effect. This provides deterministic, zero-software-overhead protection against accidental or malicious overwrites - a critical feature in safety-critical 24AA32A-I/SM deployments.

Can multiple 24AA32A-I/SM devices share the same I²C bus?

Yes - up to eight 24AA32A-I/SM devices can operate on a single I²C bus using the A0, A1, and A2 address pins to configure unique 3-bit chip addresses (1010xxx0). Each device must have a distinct combination of these pins tied to VSS or VCC. The SOT-23 variant lacks these pins and supports only one device per bus; however, the 24AA32A-I/SM in MSOP-8 fully supports multi-drop addressing per Microchip's DS20001713P specification.

What is the maximum page write size for the 24AA32A-I/SM?

The 24AA32A-I/SM supports a 32-byte page write buffer, allowing up to 32 bytes to be loaded into the internal latch and written to memory with a single Stop condition. Writes crossing physical page boundaries (every 32-byte offset: 0x000–0x01F, 0x020–0x03F, etc.) wrap around within the current page instead of advancing - requiring firmware to validate address alignment before initiating page writes. This behavior is explicitly defined in the 24AA32A-I/SM datasheet Section 6.2.

Is the 24AA32A-I/SM qualified for automotive use?

Yes - the 24AA32A-I/SM is AEC-Q100 qualified for automotive applications, meeting stress test requirements for temperature cycling, humidity, and ESD. Its industrial temperature grade (–40°C to +85°C) and 4 kV HBM ESD rating align with Grade 2 automotive reliability standards. While not marketed as a dedicated automotive part number (e.g., with "A" suffix), its qualification status and performance envelope make it suitable for body control modules, infotainment configuration, and other non-safety-critical automotive subsystems using the 24AA32A-I/SM.