Microchip Technology 24AA1025T-I/SN

Overview

24AA1025T-I/SN from Microchip Technology Inc. is a 128K × 8 (1024 kbit) I²C-compatible serial EEPROM with 1.7V–5.5V supply range, 400 kHz max clock (100 kHz below 2.5V), and industrial temperature rating (–40°C to +85°C). It features 128-byte page write buffer, hardware write-protection via WP pin, and Schmitt-trigger inputs for noise immunity - deployed in embedded systems requiring nonvolatile parameter storage under low-power constraints.

For engineers reviewing the 24AA1025T-I/SN datasheet, 24AA1025T-I/SN pinout, 24AA1025T-I/SN application, or 24AA1025T-I/SN equivalent, key selection criteria include voltage compatibility (1.7–5.5V), I²C timing compliance at target VCC, page boundary handling in firmware, and WP pin logic level configuration for field-programmable protection.

Technical Context

The 24AA1025T-I/SN operates as an I²C slave device with fixed 4-bit control code (1010b), block-select bit (B0), and two user-configurable chip address bits (A0, A1), enabling up to four devices on one bus. Its internal address space is split into two 512 kbit segments (00000h–0FFFFh and 10000h–1FFFFh), accessed via B0 in the control byte.

Write operations support byte- and page-write modes; page writes are limited to 128-byte boundaries and roll over within the current page if crossed. The device uses self-timed erase/write cycles (typ. 3 ms, max 5 ms), requires no external programming voltage, and implements acknowledge polling to detect write completion without fixed delay timing.

Key Specifications

Pinout & Package

24AA1025T-I/SN is packaged in an 8-lead SOIC (Small Outline Integrated Circuit) with 3.90 mm body width, RoHS-compliant matte tin plating, and standard JEDEC MS-012AC footprint.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24LC1025-I/SN and AT24C1024-SSHL-T, the 24AA1025T-I/SN uniquely supports 1.7V operation for ultra-low-voltage battery systems, mandates A2 tie-to-VCC for robustness verification, and offers factory programming - making it optimal for cost-sensitive, wide-VCC industrial designs requiring proven qualification.

Availability

24AA1025T-I/SN is available at Aetrix Electronics and suitable for smart metering, industrial PLCs, medical diagnostics, automotive BCMs, and portable instrumentation requiring stable component supply across extended product lifecycles.

Supply support for 24AA1025T-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 U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory products, with global manufacturing and quality certifications including ISO 9001 and AEC-Q200.

The 24AA1025T-I/SN belongs to Microchip's 24XX1025 family of I²C EEPROMs, designed specifically for low-voltage, high-reliability nonvolatile storage in space-constrained embedded systems where power efficiency and long-term data integrity are critical.

FAQ

What is the minimum operating voltage for the 24AA1025T-I/SN?

The 24AA1025T-I/SN operates down to 1.7V, enabling direct interface with 1.8V logic families and battery-powered systems where brown-out conditions occur. This is lower than the 2.5V minimum of the 24LC1025 variant, making the 24AA1025T-I/SN essential for ultra-low-power applications where supply headroom is constrained. Operation below 1.7V is not guaranteed and may result in data corruption or communication failure.

How does the A2 pin function on the 24AA1025T-I/SN?

The A2 pin on the 24AA1025T-I/SN is a non-configurable chip select input that must be hard-wired to VCC for proper device operation; leaving it floating or connecting it to VSS renders the device nonfunctional. Unlike A0 and A1, A2 does not contribute to slave addressing - its sole purpose is to serve as a hardware validation signal confirming correct board-level implementation. This design prevents accidental activation in misrouted or unpopulated configurations.

Can the 24AA1025T-I/SN perform sequential reads across its full 1024 kbit address space?

No, the 24AA1025T-I/SN restricts sequential reads to 512 kbit blocks: 00000h–0FFFFh and 10000h–1FFFFh. Attempting to read past 0FFFFh rolls the internal address pointer back to 00000h, and reading past 1FFFFh wraps to 10000h. To access the full memory linearly, software must issue separate random read commands with explicit block-select bit (B0) control - a constraint imposed by the dual-segment architecture documented in DS20001941L.

What is the actual page write time for the 24AA1025T-I/SN, and how should firmware handle it?

The 24AA1025T-I/SN has a typical page write time of 3 ms and a maximum of 5 ms. Firmware must either insert a fixed 5 ms delay after each page write command or use acknowledge polling - sending repeated Start + control byte (R/W = 0) until an ACK is received - to detect completion. Polling is preferred for real-time systems, as it avoids worst-case delays when the internal cycle finishes early, improving bus utilization and deterministic response.

Does the 24AA1025T-I/SN require external components for I²C bus operation?

Yes, the 24AA1025T-I/SN requires external pull-up resistors on both SDA and SCL lines: typically 10 kΩ for 100 kHz operation and 2 kΩ for 400 kHz, referenced to VCC. No external capacitors, level shifters, or voltage translators are needed for standard 1.7–5.5V operation. The device's Schmitt-trigger inputs and output slope control eliminate the need for additional noise-filtering components in most industrial environments.