Microchip Technology 24AA65T/SM

Overview

24AA65T/SM from Microchip Technology Inc. is a 64 Kbit (8K × 8) I²C-compatible serial EEPROM with programmable high-endurance memory blocks, 1.8–6.0 V operation, 64-byte write cache, and Schmitt-triggered I²C interface. It delivers 10 million erase/write cycles in a designated 4K-bit block and 1 million cycles elsewhere, supporting low-power embedded systems requiring frequent nonvolatile data updates - such as battery-backed configuration storage in IoT sensor nodes.

For engineers reviewing the 24AA65T/SM datasheet, 24AA65T/SM pinout, 24AA65T/SM application, or 24AA65T/SM equivalent, key selection considerations include its dual endurance rating, I²C bus speed scalability (100 kHz at 1.8 V, 400 kHz at ≥4.5 V), programmable security blocks, and SOIJ-8 package compatibility with space-constrained PCB layouts.

Technical Context

The 24AA65T/SM implements a two-wire I²C slave interface with hardware-addressable device select lines (A0–A2), enabling up to eight devices on one bus. Its internal architecture includes a 64-byte FIFO page cache, a relocatable 4K-bit ultra-high-endurance memory segment, and configurable write protection across 0–15 contiguous 4K blocks.

It features integrated V_CC monitoring for power-fail write inhibition, Schmitt-triggered SDA/SCL inputs with 50 ns spike filtering, and output slope control to suppress ground bounce. All operations - byte write, page write, current/random/sequential read - conform strictly to I²C protocol timing requirements per Table 1-2, with T_WR = 5 ms per page and self-timed erase/write cycles.

Key Specifications

Pinout & Package

24AA65T/SM is housed in an 8-pin SOIJ (Small Outline Integrated Circuit, J-bend) surface-mount package, RoHS-compliant and rated for commercial temperature range (0°C to +70°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA65T/SM, the 24LC65T/SM offers extended temperature range but excludes 1.8 V compatibility, while the AT24C64D lacks both the high-endurance block and configurable write protection - making 24AA65T/SM uniquely suited for applications demanding long-life, field-updatable, and secure parameter storage.

Availability

24AA65T/SM is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical sensors, and automotive body control modules requiring stable component supply, long-lifecycle assurance, and RoHS-compliant sourcing.

Supply support for 24AA65T/SM 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 manufacturer specializing in microcontrollers, analog devices, and memory solutions for embedded control applications.

The 24AA65T/SM belongs to Microchip's "Smart Serial EEPROM" product line, designed specifically for systems needing differentiated endurance, flexible security, and robust I²C communication in low-voltage, space-constrained environments.

FAQ

What is the maximum I²C clock frequency supported by the 24AA65T/SM?

The 24AA65T/SM supports 100 kHz I²C operation across its full 1.8–4.5 V V_CC range and scales to 400 kHz when V_CC is 4.5–6.0 V. This dual-speed capability is hardware-determined by supply voltage and requires no configuration register changes - the device automatically complies with Standard Mode or Fast Mode timing specifications per Table 1-2 in DS21073K.

How does the high-endurance block function in the 24AA65T/SM?

The 24AA65T/SM includes one user-programmable 4K-bit block rated for 10 million erase/write cycles, distinct from the remaining 60K bits rated for 1 million cycles. The block location is set via configuration byte bit S/HE=0 and upper address bits; once programmed, it retains high endurance even if overlapped by security blocks. Default location is 0x1E00–0x1FFF.

Can the 24AA65T/SM be used in a 1.8 V system with I²C Fast Mode?

No. The 24AA65T/SM supports I²C Fast Mode (400 kHz) only when V_CC is 4.5–6.0 V. At 1.8 V, it operates exclusively in Standard Mode (100 kHz). This voltage-dependent speed limitation is defined in the Device Selection Table and confirmed in Table 1-2 AC Characteristics - attempting 400 kHz at 1.8 V violates timing margins and will cause communication failure.

What happens if more than 64 bytes are written before issuing a Stop condition to the 24AA65T/SM?

When more than 64 bytes are loaded into the 24AA65T/SM's page cache before a Stop condition, the address pointer wraps around to the start of the cache (page 0), overwriting previously loaded data. Only the final 64 bytes - or fewer, if Stop is issued mid-load - are written to EEPROM upon Stop reception. No error flag is generated; the device silently discards overflowed data.

Is the NC pin on the 24AA65T/SM safe to connect to ground or VCC?

No. The NC (No Connection) pin on the 24AA65T/SM is internally unconnected and must remain floating - it is not bonded to any die structure. Connecting it to ground, VCC, or any signal risks latch-up, increased leakage, or undefined behavior. The Pin Function Table in DS21073K explicitly defines NC as "No Internal Connection", and Microchip's packaging documentation confirms this pin has no electrical function.