Microchip Technology 24AA32AF-I/P

Overview

24AA32AF-I/P from Microchip Technology Inc. is a 32 Kbit I²C-compatible serial EEPROM organized as 4K × 8-bit memory, operating from 1.7V to 5.5V with industrial temperature range (–40°C to +85°C). It features hardware write-protect for the upper 1/4 array (C00h–FFFh), 32-byte page write buffer, and Schmitt-trigger inputs for noise immunity. Used in low-power embedded systems for parameter storage, calibration data retention, and configuration backup.

For engineers reviewing the 24AA32AF-I/P datasheet, 24AA32AF-I/P pinout, 24AA32AF-I/P application, or 24AA32AF-I/P equivalent, key selection criteria include its 1.7V minimum V_CC, 1 μA max standby current, 400 kHz I²C clock support (down to 100 kHz at <2.5V), quarter-array hardware write-protection, and compatibility with standard 8-pin PDIP packaging.

Technical Context

The 24AA32AF-I/P implements a two-wire I²C interface with slave addressing via three hardware-selectable address pins (A0–A2), enabling up to eight devices on one bus. Its internal architecture includes a 32-byte page latch, self-timed erase/write cycle, and dedicated write-protect logic that samples the WP pin at the Stop bit of each write command.

It uses CMOS EEPROM technology with integrated high-voltage generator for programming, supports acknowledge polling to detect write completion, and enforces strict timing compliance per I²C specification-including THD:STA ≥ 4000 ns and TLOW ≥ 4700 ns at 1.7V ≤ V_CC < 2.5V-ensuring robust operation in noisy industrial environments.

Key Specifications

Pinout & Package

24AA32AF-I/P is supplied in 8-lead PDIP (Plastic Dual In-line Package) with 0.3-inch body width, compatible with through-hole PCB assembly and legacy prototyping workflows.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA32AF-I/P, the 24LC32AF-I/P excludes sub-2.5V operation but offers identical packaging and interface; the AT24C32D-SSHM-T provides second-source availability with no electrical or mechanical trade-offs, simplifying supply chain risk mitigation.

Availability

24AA32AF-I/P is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical diagnostics, and automotive body control modules requiring stable component supply across extended product lifecycles.

Supply support for 24AA32AF-I/P 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 24AA32AF-I/P belongs to Microchip's 24XX32AF family of I²C serial EEPROMs, designed specifically for low-power, space-constrained embedded systems needing reliable nonvolatile storage with minimal external components.

FAQ

What is the minimum operating voltage for the 24AA32AF-I/P?

The 24AA32AF-I/P operates down to 1.7V V_CC, making it compatible with 1.8V logic systems and battery-powered applications where voltage droop occurs. This is a key differentiator from the 24LC32AF-I/P, which requires ≥2.5V. The 24AA32AF-I/P maintains full I²C functionality-including 400 kHz clock support-at 2.5V and above, and automatically de-rates to 100 kHz below 2.5V to ensure timing margin.

How does the hardware write-protect feature work on the 24AA32AF-I/P?

The 24AA32AF-I/P uses the WP pin to disable writes to the upper 1/4 memory array (addresses C00h–FFFh) when tied to V_CC; writes remain enabled for the lower 3/4 (000h–BFFh). The WP state is sampled only at the Stop condition of each write command, so toggling WP mid-cycle has no effect. This allows secure storage of boot code or calibration constants without software overhead, and is fully implemented in silicon-not dependent on firmware.

Can multiple 24AA32AF-I/P devices share the same I²C bus?

Yes, up to eight 24AA32AF-I/P devices can operate on a single I²C bus using the A0, A1, and A2 address pins to configure unique 7-bit slave addresses (1010xxx). Each pin must be hardwired to V_SS or V_CC; floating connections are not permitted. This enables scalable memory expansion up to 256 Kbits (eight × 32 Kbit) with contiguous addressing-though sequential reads cannot cross device boundaries.

What is the maximum page write size supported by the 24AA32AF-I/P?

24AA32AF-I/P supports a 32-byte page write buffer, allowing up to 32 bytes to be loaded into the internal latch and written to memory in a single self-timed cycle. Page writes must stay within physical page boundaries (aligned to 32-byte offsets); crossing a boundary causes wraparound within the current page. The maximum write time is 5 ms, and the device supports acknowledge polling to detect completion without fixed delays.

Is the 24AA32AF-I/P RoHS compliant and lead-free?

Yes, the 24AA32AF-I/P is Pb-free and RoHS compliant per Microchip's DS22184A datasheet. The PDIP package uses matte tin (Sn) plating per JEDEC standards, and marking includes the "3e" Pb-free designation. All variants in the 24AA32AF/24LC32AF family meet RoHS Directive 2011/65/EU, with full compliance documentation available in Microchip's Pb-free conversion reports.