Microchip Technology AT28C256E-15JU-T

Overview

AT28C256E-15JU-T from Microchip Technology is an industrial-grade 256-Kbit paged parallel EEPROM organized as 32,768 × 8, featuring 150 ns read access time, 64-byte page write capability, and single 5V ±10% supply operation. It supports DATA polling and toggle-bit write completion detection and operates across –40°C to +85°C for embedded control and firmware storage in programmable logic controllers and industrial HMIs.

For engineers reviewing the AT28C256E-15JU-T datasheet, AT28C256E-15JU-T pinout, AT28C256E-15JU-T application, or AT28C256E-15JU-T equivalent, key selection considerations include JEDEC byte-wide pin compatibility, software/hardware data protection, 100,000-cycle endurance, CMOS/TTL I/O compatibility, and PLCC-32 packaging with industrial temperature rating.

Technical Context

The AT28C256E-15JU-T implements a paged write architecture with internal 64-byte latches and an autonomous control timer, enabling up to 64-byte writes within a single 10 ms maximum programming cycle. Its dual-line chip enable (CE) and output enable (OE) logic allows flexible bus contention management during read operations.

Hardware write protection includes V_CC sense (inhibit below 3.8 V), 5 ms power-on delay, and noise filtering on WE/CE inputs; software data protection uses a three-byte command sequence (AAh/55h/A0h) to lock writes without requiring external circuitry or voltage changes beyond standard 5 V.

Key Specifications

Pinout & Package

AT28C256E-15JU-T is packaged in a 32-lead Plastic Leaded Chip Carrier (PLCC) with JEDEC-standard byte-wide pinout and no-connect (NC) pins at positions 12 and 26. The package features gull-wing leads, 1.27 mm pitch, and conforms to JEDEC MS-016 Variation AE.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT28C256-15PU and AT28C256-15SU, the AT28C256E-15JU-T provides superior mechanical robustness via PLCC gull-wing leads, enhanced thermal dissipation, and explicit support for extended endurance (100K cycles), making it optimal for vibration-prone industrial deployments requiring long-term field reliability.

Availability

AT28C256E-15JU-T is available at Aetrix Electronics and suitable for industrial automation, medical instrumentation, and automotive electronics requiring stable component supply, long-lifecycle support, and guaranteed traceability.

Supply support for AT28C256E-15JU-T 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 global semiconductor company specializing in microcontrollers, analog devices, and nonvolatile memory solutions for industrial, automotive, and consumer applications.

The AT28C256 product line delivers high-reliability, paged parallel EEPROMs designed specifically for firmware storage, configuration retention, and calibration data logging in harsh-environment embedded systems.

FAQ

What is the endurance rating of the AT28C256E-15JU-T and how is it validated?

The AT28C256E-15JU-T is rated for 100,000 write/erase cycles, as specified in Microchip's DS20006386B datasheet Section 4.3. This endurance level applies to the "E" variant (denoted in the part marking) and is verified per JEDEC standards using accelerated life testing across the full industrial temperature range. Each AT28C256E-15JU-T unit undergoes screening to ensure compliance before shipment.

Does the AT28C256E-15JU-T require a 12 V supply for any operation?

No, the AT28C256E-15JU-T operates exclusively from a single 5 V ±10% supply for all standard read, write, and page write functions. A 12 V supply is only required for optional device identification area programming (addresses 7FC0h–7FFFh) and chip erase - both are infrequent, factory-level operations not needed for typical firmware or configuration storage use of the AT28C256E-15JU-T.

How does software data protection work on the AT28C256E-15JU-T?

Software data protection on the AT28C256E-15JU-T is enabled by writing the three-byte sequence AAh → 55h → A0h to addresses 5555h → 2AAAh → 5555h. Once activated, subsequent writes require repeating this sequence before data. The AT28C256E-15JU-T ships with protection disabled, and the feature remains active across power cycles - no external hardware or voltage changes are needed to maintain security.

Can the AT28C256E-15JU-T be used as a direct replacement for older AT28C256 variants?

Yes, the AT28C256E-15JU-T maintains full pin, timing, and functional compatibility with earlier AT28C256 versions (e.g., AT28C256-15PU), including identical JEDEC byte-wide pinout, 150 ns read access, and 64-byte page write. The "E" suffix denotes extended endurance (100K cycles), but all AC/DC specifications and command protocols remain unchanged - no PCB or firmware modifications are required when upgrading to AT28C256E-15JU-T.

What package type does the AT28C256E-15JU-T use and what are its key mechanical attributes?

The AT28C256E-15JU-T uses a 32-lead Plastic Leaded Chip Carrier (PLCC) package per JEDEC MS-016 Variation AE. Key attributes include gull-wing leads with 1.27 mm pitch, body dimensions of 12.47 mm × 14.96 mm, and a height of 3.56 mm max. It features two "DC" (don't connect) pins and two "NC" pins, all of which must remain unconnected per Microchip's design guidance for AT28C256E-15JU-T reliability.