Microchip Technology 24AA64F-I/P

Overview

24AA64F-I/P from Microchip Technology Inc. is a 64 Kbit I²C-compatible serial EEPROM organized as 8K × 8-bit memory, operating from 1.7V to 5.5V with 400 µA max read current and 1 µA max standby current at industrial temperature range (–40°C to +85°C). It features hardware write-protection for the upper 1/4 array (1800h–1FFFh), 32-byte page write buffer, and Schmitt-trigger inputs for noise immunity-used in battery-powered sensor nodes and embedded system configuration storage.

For engineers reviewing the 24AA64F-I/P datasheet, 24AA64F-I/P pinout, 24AA64F-I/P application, or 24AA64F-I/P equivalent, key selection criteria include low-voltage operation down to 1.7V, I²C clock compatibility up to 400 kHz (100 kHz below 2.5V), industrial-grade temperature rating, and cascading support for up to eight devices on one bus via A0–A2 address pins.

Technical Context

The 24AA64F-I/P implements a two-wire I²C interface with slave addressing using a fixed 4-bit control code (1010b) plus three programmable chip-select bits (A2–A0), enabling up to eight devices on a shared bus. Its internal address counter supports current-address, random, and sequential read modes, while page write operations are constrained to 32-byte boundaries without automatic wrap across physical pages.

Write protection is implemented via the WP pin, which-when tied to VCC-disables writes only to addresses 1800h–1FFFh; all other memory remains writable. The device uses self-timed erase/write cycles with typical 5 ms page write time and includes slope-controlled outputs to suppress ground bounce during SDA transitions.

Key Specifications

Pinout & Package

24AA64F-I/P is supplied in an 8-lead PDIP (Plastic Dual In-line Package) with 0.300-inch body width, suitable for through-hole prototyping and legacy PCB assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA64F-I/P, the 24LC64F-I/P offers identical functionality above 2.5V but excludes sub-2.5V operation, while the AT24C64D-SSHM-T provides voltage compatibility but removes dedicated hardware write-protection-making 24AA64F-I/P the only option supporting both ultra-low-voltage operation and physical array locking.

Availability

24AA64F-I/P is available at Aetrix Electronics and suitable for smart metering, industrial PLC backup, medical calibration storage, and automotive body control module applications requiring stable component supply across extended product lifecycles.

Supply support for 24AA64F-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 microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA64F-I/P belongs to Microchip's 24XX64F family of serial EEPROMs, designed specifically for low-power, high-reliability nonvolatile storage in battery-operated and industrial environments where voltage flexibility and data integrity are critical.

FAQ

What is the minimum operating voltage for the 24AA64F-I/P?

The 24AA64F-I/P operates down to 1.7V, making it compatible with 1.8V logic systems and energy-harvesting applications. This is a key differentiator from the 24LC64F variant, which requires a minimum of 2.5V. Operation below 2.5V reduces the maximum I²C clock frequency to 100 kHz, as specified in the DS22154B datasheet.

How does the hardware write-protect feature work on the 24AA64F-I/P?

The 24AA64F-I/P uses the WP pin to disable writes to the upper 1/4 memory array (addresses 1800h–1FFFh) when pulled high to VCC. Writes to the remaining 48 Kbit remain enabled. The WP state is sampled at the Stop bit of each write command, so toggling WP mid-operation has no effect-ensuring deterministic protection behavior during bus transactions.

Can multiple 24AA64F-I/P devices share the same I²C bus?

Yes-up to eight 24AA64F-I/P devices can operate on a single I²C bus using the A0, A1, and A2 address pins to configure unique 3-bit slave addresses. Each pin must be hardwired to VSS or VCC; floating connections are not permitted. The SOT-23 variant lacks these pins and supports only single-device configurations.

What is the typical write cycle time for a full 32-byte page on the 24AA64F-I/P?

The 24AA64F-I/P has a typical page write time of 5 ms, regardless of whether 1 or 32 bytes are written in a single page operation. This self-timed internal cycle frees the host controller to perform other tasks during the write, and acknowledge polling (repeated Start + control byte) can be used to detect completion without fixed delays.

Does the 24AA64F-I/P support standard I²C addressing and protocol?

Yes-the 24AA64F-I/P implements a standard I²C slave interface with a fixed 4-bit device identifier (1010b) followed by three programmable address bits (A2–A0) and a read/write bit. It fully complies with I²C specification timing requirements including setup/hold times, ACK generation, and Start/Stop condition detection, ensuring interoperability with all standard I²C masters.