Microchip Technology 24LC1026-E/SN

Overview

24LC1026-E/SN from Microchip Technology is a 1024 Kbit (128K × 8) I²C-compatible serial EEPROM with automotive-grade temperature range (–40°C to +125°C), 2.5V–5.5V supply, 400 kHz max clock (100 kHz at V_CC < 4.5V in E-temp), and hardware write-protection via WP pin. It supports cascaded operation of up to four devices on one bus and is used for nonvolatile configuration storage in engine control units and ADAS modules.

For engineers reviewing the 24LC1026-E/SN datasheet, 24LC1026-E/SN pinout, 24LC1026-E/SN application, or 24LC1026-E/SN equivalent, key selection criteria include its AEC-Q100-qualified automotive operating range, 128-byte page write buffer, Schmitt-trigger inputs for noise immunity, and 1 million endurance cycles with >200-year data retention.

Technical Context

The 24LC1026-E/SN implements a two-wire I²C interface with slave addressing using A1/A2 pins and block-select bit B0 to access two 512 Kbit memory segments (00000h–0FFFFh and 10000h–1FFFFh). It uses internal address pointer auto-increment for sequential reads and supports byte/page writes with self-timed erase/write cycles.

Its architecture includes on-chip HV generator for EEPROM programming, 128-byte page latches for buffered writes, and dual-voltage sense amplifiers for reliable read operations across the full V_CC and temperature range. The device samples WP at the Stop bit to enforce hardware write protection before initiating any write cycle.

Key Specifications

Pinout & Package

24LC1026-E/SN is supplied in an 8-lead SOIC package (3.90 mm body width), RoHS-compliant, with matte tin (Sn) lead finish. Pin 1 is marked by a beveled corner or laser dot; package conforms to JEDEC MS-012AA.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT24C1024-MAHM-T and BR24G1ME-3A, the 24LC1026-E/SN delivers AEC-Q100-qualified automotive operation at 400 kHz with proven field reliability in ECUs, while avoiding the cost premium of ECC or unnecessary 1 MHz capability in bandwidth-constrained control networks.

Availability

24LC1026-E/SN is available at Aetrix Electronics and suitable for engine control units, ADAS sensors, infotainment head units, and body control modules requiring stable component supply across multi-year automotive production programs.

Supply support for 24LC1026-E/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 is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and memory products, with broad automotive qualification and long-term product longevity commitments.

The 24LC1026-E/SN belongs to Microchip's 24XX1026 family of I²C EEPROMs, designed specifically for automotive and industrial applications demanding extended temperature operation, high endurance, and robust noise immunity in electrically harsh environments.

FAQ

What is the maximum I²C clock frequency supported by the 24LC1026-E/SN?

The 24LC1026-E/SN supports up to 400 kHz when V_CC ≥ 2.5V and ambient temperature is within the automotive range (–40°C to +125°C). However, if V_CC falls below 4.5V under E-temp conditions, the maximum clock rate is reduced to 100 kHz per DS20002270E specification. This voltage-dependent limitation ensures timing margin compliance across the full operating envelope. The 24LC1026-E/SN does not support 1 MHz operation - that capability is exclusive to the 24FC1026 variant.

How does hardware write-protection work on the 24LC1026-E/SN?

Hardware write-protection on the 24LC1026-E/SN is controlled by the WP pin: when tied to VCC, all write operations (byte and page) are inhibited while read operations remain fully functional. The device samples WP at the Stop bit of each command, so toggling WP mid-cycle has no effect. This behavior is implemented in silicon and requires no firmware intervention. For secure field updates, the 24LC1026-E/SN must have WP grounded during programming and reconnected to VCC afterward - a design choice confirmed in Section 2.4 and Figure 1-1 of the datasheet.

Can the 24LC1026-E/SN be used in a system with multiple EEPROMs on the same I²C bus?

Yes, the 24LC1026-E/SN supports cascading up to four devices on a single I²C bus using the A1 and A2 address pins to configure unique 2-bit chip select bits. Each device responds only when its A1/A2 combination matches the corresponding bits in the master's control byte (1010 A2 A1 B0 R/W). This enables up to 4 Mbit of contiguous EEPROM capacity. However, sequential reads cannot cross device boundaries - software must issue separate read commands per device, as stated in Section 5.1 of DS20002270E.

What is the page size and write time for the 24LC1026-E/SN?

The 24LC1026-E/SN has a 128-byte page write buffer and typical page write time of 3 ms. Page writes are limited to addresses within a single physical page boundary (e.g., 0000h–007Fh), and crossing boundaries causes wraparound instead of automatic increment. Endurance is rated per page (1,000,000 cycles), not per byte, because writing any byte in a page triggers full-page rewrite. This behavior is documented in Section 6.2 and Note on page 9 of DS20002270E, and applies identically to the 24LC1026-E/SN.

Is the 24LC1026-E/SN AEC-Q100 qualified?

Yes, the 24LC1026-E/SN is automotive-grade (E-temp) and qualified per AEC-Q100 Rev G requirements, with operating temperature range –40°C to +125°C. Its qualification is evidenced by the 'E' suffix in the part number, explicit listing in the Device Selection Table under "Automotive (E)" temperature range, and inclusion of E-temp-specific AC/DC specifications in Tables 1-1 and 1-2 of DS20002270E. This makes the 24LC1026-E/SN suitable for under-hood and safety-critical applications where industrial-grade parts would fail qualification.