Microchip Technology 24LC1026T-I/SM

Overview

24LC1026T-I/SM from Microchip Technology is a 128K × 8 (1024 Kbit) I²C-compatible serial EEPROM with hardware write-protection, 128-byte page write buffer, and industrial temperature range (–40°C to +85°C). It operates from 2.5V to 5.5V, supports up to 400 kHz clock frequency, and delivers ≤450 µA read current and ≤5 µA standby current - ideal for battery-backed data logging in industrial controllers and embedded sensor nodes.

For engineers reviewing the 24LC1026T-I/SM datasheet, 24LC1026T-I/SM pinout, 24LC1026T-I/SM application, or 24LC1026T-I/SM equivalent, key selection criteria include VCC voltage compatibility (2.5–5.5V), I²C timing compliance at 400 kHz, WP pin behavior under logic-high write-inhibit, and cascading support across four devices on one bus using A1/A2 address bits.

Technical Context

The 24LC1026T-I/SM implements a two-wire I²C interface with Schmitt-trigger inputs on SDA/SCL for noise immunity and slope-controlled outputs to suppress ground bounce. Its internal architecture includes dual 512 Kbit memory blocks accessed via block-select bit B0, enabling contiguous addressing only within each 512 Kbit segment (00000h–0FFFFh and 10000h–1FFFFh).

Write operations use self-timed erase/write cycles with 3 ms typical page write time and automatic address pointer incrementing. Acknowledge polling is supported during internal write cycles, and hardware write-protection is enforced by sampling the WP pin at the Stop condition - no writes occur when WP = VCC, regardless of command validity.

Key Specifications

Pinout & Package

24LC1026T-I/SM uses an 8-lead SOIC package (3.90 mm width, JEDEC MS-012), marked "I/SM" per Microchip's packaging specification C04-018D. Pin 1 is index-marked; package is RoHS-compliant and rated for industrial temperature operation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 24AA1026-I/SM, the 24LC1026T-I/SM trades lower-voltage operation for improved VCC stability margin above 2.5V; versus AT24C1024-SSHM-T, it avoids WP polarity inversion and maintains native Microchip address encoding - simplifying firmware reuse and qualification.

Availability

24LC1026T-I/SM is available at Aetrix Electronics and suitable for industrial sensor calibration storage, medical device configuration memory, and automotive body control modules requiring stable component supply across extended temperature ranges and long product lifecycles.

Supply support for 24LC1026T-I/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 leading provider of microcontrollers, analog components, and memory solutions, headquartered in Chandler, Arizona, with global design and manufacturing operations.

The 24LC1026T-I/SM belongs to Microchip's 24XX1026 family of I²C serial EEPROMs, engineered for robust, low-power nonvolatile data storage in industrial, medical, and automotive applications demanding high endurance and long-term data retention.

FAQ

What is the minimum VCC voltage required for reliable operation of the 24LC1026T-I/SM?

The 24LC1026T-I/SM requires a minimum VCC of 2.5V for guaranteed operation across its full industrial temperature range (–40°C to +85°C). Unlike the 24AA1026 variant, it does not support operation below 2.5V - attempting to power the 24LC1026T-I/SM at 2.4V or lower may result in unpredictable read/write behavior or failure to acknowledge I²C commands.

How does the WP pin function on the 24LC1026T-I/SM during active write cycles?

The WP pin on the 24LC1026T-I/SM is sampled only at the Stop condition of each write command. If WP = VCC at that instant, the entire write cycle is inhibited - no data is written, but the device still acknowledges the command and accepts subsequent instructions immediately. Toggling WP during an ongoing write has no effect; protection is strictly edge-triggered on Stop.

Can the 24LC1026T-I/SM perform sequential reads across its full 1024 Kbit address space?

No. The 24LC1026T-I/SM divides its memory into two 512 Kbit blocks (00000h–0FFFFh and 10000h–1FFFFh). Sequential reads automatically roll over within each block but cannot cross the 0FFFFh → 10000h boundary. To read the full array sequentially, software must issue separate read commands for each block with explicit address restarts.

What is the maximum number of 24LC1026T-I/SM devices that can share a single I²C bus?

Up to four 24LC1026T-I/SM devices can be cascaded on one I²C bus using the A1 and A2 address pins. Each device must have a unique combination of A1/A2 logic levels (00, 01, 10, or 11) to generate distinct 7-bit slave addresses (1010 A2 A1 B0). No external address decoder is needed - addressing is handled entirely by the I²C protocol.

Does the 24LC1026T-I/SM support 1 MHz I²C clock frequency?

No. The 24LC1026T-I/SM supports a maximum clock frequency of 400 kHz at VCC ≥ 2.5V. For 1 MHz operation, Microchip's 24FC1026 variant is required - it is pin-compatible but has different VCC min/max (1.8V–5.5V) and AC timing specifications. Using 24LC1026T-I/SM at 1 MHz violates its AC characteristics and may cause communication failures.