Microchip Technology SST49LF080A-33-4C-NHE-T

Overview

SST49LF080A-33-4C-NHE-T from Microchip Technology (formerly Silicon Storage Technology) is an 8 Mbit LPC interface flash memory IC designed for BIOS/firmware storage in PC and Internet appliance platforms compliant with Intel Low Pin Count (LPC) Interface Specification 1.0. It delivers 1024K × 8 organization, single 3.0–3.6 V operation, 33 MHz clock support in LPC mode, and hardware write protection via WP# and TBL# pins. It serves as a boot memory device in embedded x86 systems requiring reliable, low-pin-count firmware storage.

For engineers reviewing the SST49LF080A-33-4C-NHE-T datasheet, SST49LF080A-33-4C-NHE-T pinout, SST49LF080A-33-4C-NHE-T application, or SST49LF080A-33-4C-NHE-T equivalent, this page provides verified technical context, LPC/PP mode behavior, sector/block erase timing, SuperFlash® reliability metrics, and hardware-level interface constraints - all confirmed against DS20005086B Rev. B.

Technical Context

The SST49LF080A-33-4C-NHE-T operates in two mutually exclusive modes: LPC mode (enabled by MODE = low) using 4-bit LAD[3:0] multiplexed address/data bus with LFRAME# and LCLK, and Parallel Programming (PP) mode (MODE = high) using 11-pin multiplexed address (A10–A0) and 8-bit DQ[7:0] I/O. In LPC mode, it supports JEDEC SDP command sequences, Data# Polling (DQ7), and Toggle Bit (DQ6) for end-of-write detection.

LPC mode implements full 32-bit address decoding with ID[3:0] strapping for multi-device selection, supporting up to 16 devices on one bus. Hardware write protection is implemented independently via TBL# (locks top 64 KB boot block) and WP# (locks remaining sectors), both requiring stable logic levels before and during erase/program operations.

Key Specifications

Pinout & Package

Package: 32-lead TSOP (8 mm × 14 mm), RoHS-compliant, lead-free. Pin compatibility confirmed with 32-lead PLCC variant per DS20005086B Figures 2–3 and Table 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar LPC flash memory applications.

Compared with W39V080FAAIG, SST49LF080A-33-4C-NHE-T offers deterministic erase timing and integrated GPI inputs; compared with MX29LV800CTTI-90G, it eliminates 16+ address lines and reduces pin count by >50%, enabling compact LPC-based designs.

Availability

SST49LF080A-33-4C-NHE-T is available at Aetrix Electronics and suitable for PC motherboard design, embedded x86 firmware development, and industrial Internet appliance production requiring stable component supply, long-life firmware storage, and Intel LPC specification compliance.

Supply support for SST49LF080A-33-4C-NHE-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 acquired Silicon Storage Technology (SST) in 2016 and maintains full support for the SuperFlash® portfolio, including legacy LPC flash devices. SST pioneered high-reliability flash technology for embedded firmware applications.

The SST49LF080A-33-4C-NHE-T belongs to the LPC Flash product line, engineered specifically for BIOS, UEFI, and firmware storage in resource-constrained x86 platforms where low pin count, hardware write protection, and in-system programmability are critical.

FAQ

What interface modes does the SST49LF080A-33-4C-NHE-T support, and how is mode selected?

The SST49LF080A-33-4C-NHE-T supports two mutually exclusive interface modes: LPC mode (for in-system operation) and Parallel Programming (PP) mode (for factory programming). Mode selection is controlled by the MODE pin: logic low enables LPC mode (default, internally pulled down), and logic high enables PP mode. The MODE pin must be set at power-up and remain static during operation; changing it mid-operation causes undefined behavior. In LPC mode, communication occurs over LAD[3:0], LCLK, and LFRAME#; in PP mode, it uses multiplexed A10–A0 and DQ[7:0] with R/C# control. This dual-mode capability allows flexible deployment across development and production environments.

How does hardware write protection work on the SST49LF080A-33-4C-NHE-T?

The SST49LF080A-33-4C-NHE-T implements independent hardware write protection via two dedicated pins: TBL# (Top Block Lock) and WP# (Write Protect). TBL# protects the top 64 KB boot block (16 × 4 KB sectors); when driven low, it prevents program/erase of that region. WP# protects all remaining sectors; when low, it disables programming to those areas. Both pins must be externally terminated - neither may float - and their states must be stable before initiating any erase or program operation. A logic change during an active operation may corrupt memory contents. This dual-layer protection enables secure boot configurations where critical firmware resides in the top block and application code occupies lower addresses.

What is the significance of SuperFlash® technology in the SST49LF080A-33-4C-NHE-T?

SuperFlash® technology in the SST49LF080A-33-4C-NHE-T employs a split-gate cell architecture with a thick-oxide tunneling injector, delivering superior reliability versus conventional flash. Key benefits include fixed 18 ms sector-erase and 14 µs byte-program times - independent of accumulated erase/program cycles - eliminating the need for software calibration over lifetime. It achieves >100,000 endurance cycles and >100 years data retention while consuming less energy per operation due to lower programming current and shorter erase duration. This makes SST49LF080A-33-4C-NHE-T especially suitable for applications requiring frequent firmware updates without degradation in timing predictability or longevity.

Can multiple SST49LF080A-33-4C-NHE-T devices share the same LPC bus?

Yes, up to 16 SST49LF080A-33-4C-NHE-T devices can share a single LPC bus using hardware ID strapping via ID[3:0] pins. The boot device must be strapped to ID[3:0] = 0000; subsequent devices use sequential binary values (0001, 0010, etc.). Each device decodes its assigned 4 MB memory window based on address bits A24:A23 and A21:A20, which are inverted relative to the hardware strap. This enables scalable firmware storage (e.g., 16 × 8 Mbit = 128 Mbit) without additional address lines or bus arbitration. System BIOS must support multi-device enumeration, and all devices on the bus must be identical density (8 Mbit) per the datasheet requirement.

How is end-of-write detection implemented on the SST49LF080A-33-4C-NHE-T?

The SST49LF080A-33-4C-NHE-T provides two hardware-supported methods for end-of-write detection: Data# Polling (monitoring DQ7) and Toggle Bit (monitoring DQ6). During program/erase, DQ7 outputs complemented data (or '0' during erase) until completion, then returns true value; DQ6 toggles between 0 and 1 until completion, then stabilizes. Both methods are accessed via standard LPC read cycles and eliminate fixed delay loops. To avoid spurious reads caused by asynchronous completion, the datasheet recommends reading the location twice after detecting stabilization - if both reads match, the operation is confirmed complete. This ensures robust, timing-agnostic firmware update routines in real-world systems.