Microchip Technology AT49LW080-33JX-T

Overview

AT49LW080-33JX-T from Microchip Technology is a 8-Mbit Firmware Hub (FWH) Flash memory IC designed for PC BIOS applications, compatible with Intel 82802AC/AB and supporting Intel 8XX/E7XXX/E8XXX chipsets. It delivers uniform 64-Kbyte sectors, automated byte-program and sector-erase operations, and dual-interface operation (FWH and A/A Mux) at 3.3V I/O with 33 MHz PCI clock synchronization.

For engineers reviewing the AT49LW080-33JX-T datasheet, AT49LW080-33JX-T pinout, AT49LW080-33JX-T application, or AT49LW080-33JX-T equivalent, key selection criteria include FWH interface compliance, hardware write-protection via TBL/WP pins, 32-pin PLCC or 40-pin TSOP package options, and support for both 3.3V-only and 12V-assisted programming modes.

Technical Context

The AT49LW080-33JX-T implements a dual-mode interface architecture: Firmware Hub (FWH) for in-system operation and Address/Address Multiplexed (A/A Mux) for manufacturing programming. Its Command User Interface (CUI) arbitrates between interfaces and initiates internal automation upon valid command sequences.

FWH mode uses a 5-signal synchronous interface (FWH[4:0], CLK, RST/INIT) compliant with PCI timing at 33 MHz, supporting x8 reads/writes and register-based sector locking. A/A Mux mode employs an 11-pin multiplexed address + 8-pin data bus with R/C control, enabling fast on-board programming but disabling security features and registers.

Key Specifications

Pinout & Package

AT49LW080-33JX-T is available in 32-lead PLCC and 40-lead TSOP packages. Pin functions are dual-mode: FWH interface dominates system operation; A/A Mux mode activates during programming. Pin roles differ by interface mode - see table below for FWH-mode assignments (default operational mode).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Firmware Hub Flash memory applications.

Compared with Intel 82802AB and SST39VF800A-70-4C-NHE, the AT49LW080-33JX-T uniquely combines native FWH interface compliance, dual-mode programmability, and dedicated hardware write-protection - delivering lower system integration effort and higher firmware security assurance.

Availability

AT49LW080-33JX-T is available at Aetrix Electronics and suitable for desktop motherboard BIOS storage, server platform firmware hub, and industrial PC boot memory applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant sourcing.

Supply support for AT49LW080-33JX-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 leading provider of microcontroller, analog, FPGA, and memory solutions, serving automotive, industrial, communications, and computing markets with vertically integrated silicon and software offerings.

The AT49LW080-33JX-T belongs to Microchip's Firmware Hub Flash memory product line, engineered specifically to replace Intel 82802-series devices in PC and server BIOS applications while adding enhanced manufacturability and environmental compliance.

FAQ

What interface standards does the AT49LW080-33JX-T support?

The AT49LW080-33JX-T supports two distinct interfaces: Firmware Hub (FWH) for in-system operation compliant with Intel LPC bus specifications, and Address/Address Multiplexed (A/A Mux) for high-speed manufacturing programming. FWH mode uses a 5-signal synchronous interface (FWH[4:0], CLK, RST/INIT) at 33 MHz, while A/A Mux mode uses an 11-pin multiplexed address + 8-pin data bus controlled by the R/C pin. The IC pin selects the active interface at power-up.

How does hardware write protection work on the AT49LW080-33JX-T?

The AT49LW080-33JX-T implements dual hardware write-protection via dedicated TBL (Top Boot Lock) and WP (Write Protect) pins. TBL, when low, physically prevents program or erase operations on sector 15 (the top 64-Kbyte sector), regardless of software lock register state. WP, when low, enforces the same protection on sectors 0–14. Both pins are sampled at the start of each operation and operate independently - changing their state mid-operation may cause unpredictable results.

What are the voltage requirements for programming the AT49LW080-33JX-T?

The AT49LW080-33JX-T supports two VPP configurations: 3.3 V (tied to VCC for simple low-power designs) or 12 V (for fastest factory programming throughput). VCC must be maintained at 3.3 V ± 0.3 V in all cases. Internal VPP detection automatically configures erase/program logic; applying invalid VPP (e.g., 5 V) produces spurious results and must be avoided. The 12 V VPP option is rated for ≤80 hours cumulative over device lifetime.

Is the AT49LW080-33JX-T pin-compatible with Intel 82802AB/AC devices?

Yes, the AT49LW080-33JX-T is functionally and pin-compatible with Intel 82802AB and 82802AC Firmware Hub devices. It replicates the same 32-pin PLCC and 40-pin TSOP footprints, identical FWH signal mapping (FWH[4:0], CLK, RST, INIT, ID[3:0], TBL, WP), and matching timing parameters per Intel FWH specification v1.1. This enables direct replacement in existing designs without PCB or firmware changes.

What package options are available for the AT49LW080-33JX-T?

The AT49LW080-33JX-T is offered in two industry-standard packages: 32-lead Plastic Leaded Chip Carrier (PLCC) and 40-lead Thin Small Outline Package (TSOP). Both packages support Pb/Halide-free (green) construction. The PLCC variant uses a square body with J-leads for through-hole or surface-mount assembly; the TSOP variant features a rectangular body with gull-wing leads optimized for high-density PCB layouts and automated reflow soldering.