Microchip Technology 24AA32A-I/MS

Overview

24AA32A-I/MS from Microchip Technology is a 32-Kbit I²C-compatible serial EEPROM organized as 4K × 8-bit, operating from 1.7V to 5.5V with industrial temperature range (–40°C to +85°C) and housed in an 8-lead MSOP package. It features 32-byte page write buffer, hardware write-protection via WP pin, and Schmitt-trigger inputs for noise immunity - deployed in embedded system configuration storage, sensor calibration data retention, and power-fail-safe parameter backup.

For engineers reviewing the 24AA32A-I/MS datasheet, 24AA32A-I/MS pinout, 24AA32A-I/MS application, or 24AA32A-I/MS equivalent, key selection considerations include low-voltage operation down to 1.7V, 400 kHz I²C clock support at V_CC ≥ 2.5V, 1 µA standby current, and verified 1 million erase/write cycles with >200-year data retention - critical for battery-powered and long-lifecycle industrial designs.

Technical Context

The 24AA32A-I/MS implements a two-wire I²C interface with open-drain SDA/SCL pins requiring external pull-ups, supports up to eight devices on one bus via A0–A2 address inputs, and uses internal address pointer logic for sequential, random, and current-address read modes. Its page-write architecture buffers up to 32 bytes before initiating self-timed internal write cycle.

Write protection is controlled solely by the WP pin state (VSS = enabled, VCC = inhibited), sampled at Stop condition; Schmitt-trigger inputs and output slope control suppress ground bounce and noise-induced false transitions. Acknowledge polling enables host-driven timing synchronization during write cycles.

Key Specifications

Pinout & Package

8-Lead MSOP (3×3 mm body, 0.65 mm pitch) with exposed pad optional to VSS or floating per Microchip Drawing C04-111-MS Rev F.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC32A-I/MS, the 24AA32A-I/MS enables true 1.8V system integration, while AT24C32D-MAHM-E offers higher-speed I²C - both preserve the same 8-lead MSOP layout and core EEPROM functionality required for drop-in validation in existing PCBs.

Availability

24AA32A-I/MS is available at Aetrix Electronics and suitable for smart metering, industrial sensor nodes, medical diagnostics, and automotive body control modules requiring stable component supply across extended product lifecycles.

Supply support for 24AA32A-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 leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA32A-I/MS belongs to Microchip's serial EEPROM product line, engineered for ultra-low-power, high-reliability nonvolatile storage in space-constrained embedded systems where voltage flexibility and long-term data integrity are essential.

FAQ

What is the minimum supply voltage for reliable operation of the 24AA32A-I/MS?

The 24AA32A-I/MS guarantees full functionality down to 1.7V across its industrial temperature range. At V_CC < 2.5V, I²C clock frequency is limited to 100 kHz to maintain timing margins. This makes the 24AA32A-I/MS uniquely suited for 1.8V microcontroller interfaces without level-shifting circuitry - a key differentiator from the 24LC32A-I/MS, which requires ≥2.5V.

How does the WP pin affect write operations in the 24AA32A-I/MS?

In the 24AA32A-I/MS, the WP pin is sampled at the Stop condition of each write command. When tied to VCC, all write operations (byte and page) are inhibited - the device acknowledges the command but performs no memory programming. Reads remain fully functional. This hardware lock prevents accidental overwrites during power-up/down or firmware glitches, eliminating reliance on software write-enable sequences.

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

Yes - the 24AA32A-I/MS supports up to eight devices on one I²C bus using the A0, A1, and A2 address inputs. Each combination of logic levels on these pins sets a unique 3-bit chip address, allowing individual addressing within the base 1010xxxx client address format. The MSOP package retains all three address pins, unlike the SOT-23 variant which omits them.

What is the maximum write cycle time for a full 32-byte page in the 24AA32A-I/MS?

The 24AA32A-I/MS specifies a maximum write cycle time of 5 ms for both byte and page writes. This self-timed duration applies after the host issues the Stop condition - no additional delay is required in firmware. Acknowledge polling (repeated Start + control byte) can be used to detect completion precisely, enabling optimal bus utilization in time-sensitive applications.

Is the 24AA32A-I/MS RoHS compliant and AEC-Q100 qualified?

Yes, the 24AA32A-I/MS is RoHS compliant and AEC-Q100 qualified for automotive applications. Its qualification covers stress testing per Grade 2 (–40°C to +105°C ambient) requirements, confirming reliability for under-hood and body-control use cases. The "I" suffix denotes industrial temperature grade (–40°C to +85°C), fully aligned with AEC-Q100 thermal test profiles.