Microchip Technology 24AA65/SM

Overview

24AA65 from Microchip Technology Inc. is a 64 Kbit (8K × 8) I²C-compatible serial EEPROM with programmable high-endurance memory blocks, 1.8V–6.0V operation, 64-byte input cache, and Schmitt-triggered I²C interface. It delivers 10 million write cycles in a user-selectable 4K-bit block and 1 million cycles elsewhere, supporting low-power embedded systems requiring frequent nonvolatile data logging.

For engineers reviewing the 24AA65 datasheet, 24AA65 pinout, 24AA65 application, or 24AA65 equivalent, key selection criteria include its dual endurance rating, 2 ms typical byte write time, 400 kHz Fast Mode support above 4.5V, programmable security for up to 15 × 4K blocks, and compatibility with multi-device I²C buses up to 512 Kbits.

Technical Context

The 24AA65 implements a two-wire I²C slave interface with hardware-addressable device select pins (A0–A2), enabling up to eight devices on one bus. Its internal architecture includes a 64-byte FIFO page cache, dual-voltage VDD monitor, and self-timed erase/write cycles with automatic power-down after Stop condition receipt.

It supports three read modes (current address, random, sequential) and two write modes (byte and page), with acknowledge polling for write completion detection. The device features programmable high-endurance (10M cycle) and standard endurance (1M cycle) memory regions, plus configurable write protection across contiguous 4K-block ranges.

Key Specifications

Pinout & Package

24AA65 is available in 8-pin SOIJ (Small Outline Integrated Circuit, J-bend) package - surface-mount compatible with automated assembly and compact PCB layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA65, the 24LC65 sacrifices 1.8V compatibility and automotive qualification for identical feature set at higher minimum voltage, while AT24C64D trades off programmable endurance and security for lower quiescent current and broader legacy design adoption.

Availability

24AA65 is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical sensors, and automotive telematics requiring stable component supply across extended product lifecycles.

Supply support for 24AA65 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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory solutions for embedded control applications.

The 24AA65 belongs to Microchip's "Smart Serial EEPROM" product line, designed specifically for systems needing field-programmable endurance partitioning, multi-device I²C scalability, and robust noise immunity in harsh electrical environments.

FAQ

What is the maximum I²C clock frequency supported by the 24AA65?

The 24AA65 supports 100 kHz Standard Mode operation across its full 1.8V–6.0V supply range, and 400 kHz Fast Mode operation when VCC is between 4.5V and 6.0V. This dual-speed capability allows seamless integration into both legacy 100 kHz designs and higher-throughput systems without changing the device footprint or firmware interface layer.

How does the 24AA65 implement its high-endurance memory block?

The 24AA65 allows users to designate one 4K-bit block (e.g., starting at 0x1E00) for 10 million erase/write cycles via configuration byte programming. This block retains its high-endurance status even if overlapped by security protection. The remaining 60K bits operate at 1 million cycles. Once set, the high-endurance location cannot be changed if security has been enabled with nonzero length.

Can multiple 24AA65 devices share the same I²C bus?

Yes - the 24AA65 uses hardware address pins A0, A1, and A2 to generate unique 7-bit slave addresses, allowing up to eight devices on a single I²C bus. When combined, they provide up to 512 Kbits of contiguous EEPROM space. Address bits A0–A2 map directly to bits 13–15 of the extended memory address space for seamless software abstraction.

What is the purpose of the 64-byte input cache in the 24AA65?

The 64-byte FIFO cache enables burst loading of up to eight pages (8 bytes each) before initiating the internal write cycle. This decouples host I²C transaction timing from EEPROM programming latency, allowing the master to transmit data at full bus speed and then poll for completion - improving overall system throughput and reducing CPU wait states during firmware updates.

Does the 24AA65 require external components for reliable I²C operation?

Yes - the SDA and SCL lines require external pull-up resistors to VCC. Recommended values are 10 kΩ for 100 kHz operation and 2 kΩ for 400 kHz Fast Mode. No additional filtering or level-shifting circuitry is needed due to integrated Schmitt triggers, noise filters, and slope control on output drivers - simplifying BOM and layout for space-constrained designs.