Microchip Technology 24AA1026T-I/ST

Overview

24AA1026T-I/ST from Microchip Technology 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-protect (WP pin), Schmitt-trigger inputs, and >1 million erase/write cycles - deployed in embedded systems for configuration storage, calibration data retention, and firmware parameter backup.

For engineers reviewing the 24AA1026T-I/ST datasheet, 24AA1026T-I/ST pinout, 24AA1026T-I/ST application, or 24AA1026T-I/ST equivalent, this page delivers verified electrical specs, validated 8-pin SOIC package mapping, confirmed I²C timing constraints (THIGH/TLOW/TSU:DAT), and real-world use cases in power metering, medical sensor nodes, and industrial PLCs.

Technical Context

The 24AA1026T-I/ST implements a two-wire I²C slave interface with fixed 4-bit control code (1010b) and user-configurable A1/A2 address bits enabling up to four devices on one bus. Its internal architecture includes dual 512 Kbit memory blocks selected via B0 bit, with automatic address pointer roll-over within each 64 KB segment (0000h–FFFFh and 10000h–1FFFFh).

Write operations support byte and page modes, with self-timed internal erase/write cycles (typ. 3 ms, max 5 ms). The device uses on-chip HV generator for programming, incorporates slope-controlled outputs to suppress ground bounce, and samples WP state at Stop condition to enforce hardware write protection across full 1024 Kbit array.

Key Specifications

Pinout & Package

24AA1026T-I/ST is housed in an 8-lead SOIC (Small Outline Integrated Circuit) package, 3.90 mm body width, RoHS-compliant, with gull-wing leads 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 24LC1026T-I/ST and 24FC1026T-I/ST, the 24AA1026T-I/ST provides the widest low-voltage compatibility (down to 1.7V) and lowest standby current (5 µA), making it optimal for ultra-low-power battery systems where voltage headroom is constrained and longevity is prioritized over raw speed.

Availability

24AA1026T-I/ST is available at Aetrix Electronics and suitable for smart energy metering, medical sensor calibration, and industrial PLC configuration requiring stable component supply across multi-year production cycles.

Supply support for 24AA1026T-I/ST 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 microcontroller, analog, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24AA1026T-I/ST belongs to Microchip's 24XX1026 family of I²C serial EEPROMs, engineered for robust nonvolatile data storage in space-constrained, low-power embedded systems across industrial, medical, and consumer applications.

FAQ

What is the minimum VCC voltage supported by the 24AA1026T-I/ST?

The 24AA1026T-I/ST operates down to 1.7V, enabling direct integration with 1.8V logic families and extending functionality during brown-out conditions. This specification is validated across the full industrial temperature range (–40°C to +85°C) and is distinct from the 2.5V minimum of the 24LC1026T-I/ST variant. Operation below 1.7V may result in undefined behavior or failed write cycles.

How does the WP pin function on the 24AA1026T-I/ST?

The WP (Write-Protect) pin on the 24AA1026T-I/ST is sampled only at the Stop condition of each I²C write command. When tied to VCC, it disables all write operations (byte and page) while permitting unrestricted reads. Toggling WP during an active write cycle has no effect - protection state is latched at Stop edge. This behavior ensures deterministic firmware update control in safety-critical systems.

Can the 24AA1026T-I/ST perform sequential reads across its full 1024 Kbit address space?

No. The 24AA1026T-I/ST divides memory into two 512 Kbit blocks (00000h–FFFFh and 10000h–1FFFFh). Sequential reads automatically roll over within each block but cannot cross the 64 KB boundary at 10000h. To read across both blocks, software must issue separate random read commands with explicit B0 bit control - a constraint confirmed in Section 5.1 of DS20002270E.

What is the maximum page write size for the 24AA1026T-I/ST?

The 24AA1026T-I/ST supports a maximum page write size of 128 bytes, aligned to physical page boundaries starting at addresses divisible by 128 (e.g., 0000h, 0080h, 0100h). Attempting to write across a page boundary causes wraparound within the current page - not continuation into the next. This behavior is explicitly documented in Section 6.2 and Figure 6-2 of the datasheet.

Does the 24AA1026T-I/ST support 1 MHz I²C clock frequency?

No. The 24AA1026T-I/ST supports up to 400 kHz at VCC ≥2.5V and 100 kHz at VCC <2.5V. Only the 24FC1026T-I/ST variant supports 1 MHz operation (with 400 kHz limit below 2.5V). Using 1 MHz clock with 24AA1026T-I/ST violates AC timing specifications (THIGH min = 600 ns, TLOW min = 1300 ns), risking communication failure or data corruption.