Microchip Technology 24AA64F-I/SN

Overview

24AA64F-I/SN 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 (I-temp). It features hardware write-protect for the upper 1/4 array (1800h–1FFFh), 32-byte page write buffer, and Schmitt-trigger inputs for noise immunity-used in low-power embedded systems such as battery-powered sensors and industrial control modules.

For engineers reviewing the 24AA64F-I/SN datasheet, 24AA64F-I/SN pinout, 24AA64F-I/SN application, or 24AA64F-I/SN equivalent, key selection criteria include its 1.7V minimum VCC, industrial temperature range (−40°C to +85°C), 400 kHz I²C clock support, and SOT-23-compatible 8-pin SOIC package with three address pins enabling multi-device bus configuration.

Technical Context

The 24AA64F-I/SN implements a standard two-wire I²C interface with slave addressing via A0–A2 pins, supporting up to eight devices on one bus. Its internal architecture includes an 8K × 8-bit nonvolatile memory array, page write buffer, and address pointer logic that auto-increments during sequential reads.

Write protection is controlled by the WP pin: tied to VSS enables full-array writes; tied to VCC disables writes only to addresses 1800h–1FFFh. The device uses self-timed erase/write cycles with typical 5 ms page write time and supports acknowledge polling to detect write completion without fixed delays.

Key Specifications

Pinout & Package

24AA64F-I/SN is supplied in an 8-lead SOIC package (3.90 mm body width), RoHS-compliant and Pb-free. Pin assignments are identical across PDIP, SOIC, TSSOP, MSOP, and TDFN variants per Microchip DS22154B.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC64F-I/SN, the 24AA64F-I/SN enables lower-voltage operation critical for energy-harvesting designs, while AT24C64D-SSHM-T offers broader temperature tolerance but sacrifices hardware write protection-making 24AA64F-I/SN optimal for cost-sensitive industrial and medical applications needing robust, low-power, pin-level data security.

Availability

24AA64F-I/SN is available at Aetrix Electronics and suitable for industrial control systems, medical wearables, and smart sensor nodes requiring stable component supply with guaranteed long-term availability and consistent parametric performance.

Supply support for 24AA64F-I/SN 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/SN belongs to Microchip's 24XX64F family of I²C serial EEPROMs, engineered specifically for ultra-low-power, high-reliability data storage in battery-operated and industrial embedded systems.

FAQ

What is the minimum supply voltage required for reliable operation of the 24AA64F-I/SN?

The 24AA64F-I/SN operates reliably down to 1.7V VCC across its full industrial temperature range (−40°C to +85°C). This allows direct integration with 1.8V logic families and eliminates the need for voltage translation in low-power sensor nodes. Below 2.5V, the maximum I²C clock frequency is limited to 100 kHz to maintain timing margins, as specified in Microchip DS22154B Section 1.2.

How does the hardware write-protect feature function on the 24AA64F-I/SN?

The WP pin on the 24AA64F-I/SN controls write access to the upper 1/4 memory array (addresses 1800h–1FFFh). When WP is tied to VCC, writes to this region are blocked while reads remain fully functional; tying WP to VSS enables full-array write capability. The pin is sampled at the Stop bit of each write command, so toggling WP mid-operation has no effect-ensuring deterministic protection behavior in safety-critical firmware storage.

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

Yes, up to eight 24AA64F-I/SN 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 either VSS or VCC to define its bit value. This enables scalable memory expansion-for example, eight devices provide 512 Kbits total address space-without requiring additional I²C buses or multiplexers.

What is the typical write cycle time for page writes on the 24AA64F-I/SN?

The 24AA64F-I/SN has a typical page write cycle time of 5 ms, applicable to both single-byte and up to 32-byte page writes. During this self-timed internal cycle, the device does not respond to I²C commands (no ACK), enabling reliable acknowledge polling to detect completion. This fixed timing eliminates the need for software delays and ensures predictable bus arbitration in real-time systems using the 24AA64F-I/SN.

Is the 24AA64F-I/SN compatible with standard-mode I²C controllers?

Yes, the 24AA64F-I/SN is fully compliant with standard-mode (100 kHz) and fast-mode (400 kHz) I²C specifications. Its Schmitt-trigger inputs on SDA and SCL provide noise immunity, and open-drain outputs meet I²C electrical requirements. Pull-up resistors (2 kΩ typical for 400 kHz) are required on both lines. The device responds to the standard 7-bit slave address format with control code '1010' followed by A2–A0 bits and R/W bit-ensuring drop-in compatibility with existing I²C firmware stacks.