Microchip Technology SST39VF020-70-4I-WHE-T

Overview

SST39VF020-70-4I-WHE-T from Microchip Technology (formerly Silicon Storage Technology) is a 2 Mbit (256K × 8) CMOS Multi-Purpose Flash memory IC designed for nonvolatile program, configuration, and data storage in embedded systems. It operates from 2.7–3.6 V, features 70 ns read access time, 100,000 write/erase cycles endurance, and >100 years data retention - deployed in industrial control firmware updates and boot code storage.

For engineers reviewing the SST39VF020-70-4I-WHE-T datasheet, SST39VF020-70-4I-WHE-T pinout, SST39VF020-70-4I-WHE-T application, or SST39VF020-70-4I-WHE-T equivalent, key selection criteria include its 2.7–3.6 V single-supply operation, JEDEC-standard x8 parallel interface, sector-erase architecture (4 KB uniform sectors), SuperFlash® reliability, and industrial temperature range (−40°C to +85°C).

Technical Context

This device implements SST's proprietary SuperFlash® technology with split-gate cell design and thick-oxide tunneling injector, enabling fixed erase/program times independent of cycle count - eliminating system-level de-rating over lifetime. It uses standard microprocessor bus timing with latched address/data and supports both CE#- and WE#-controlled command sequences.

Write operations require JEDEC-compliant three-byte (Byte-Program) or six-byte (Sector/Chip-Erase) software data protection sequences. End-of-write detection is implemented via Data# Polling (DQ7) and Toggle Bit (DQ6), both valid after the fourth (Program) or sixth (Erase) WE#/CE# pulse edge.

Key Specifications

Pinout & Package

32-lead TSOP (8 mm × 14 mm) package with JEDEC-standard x8 parallel interface pinout. Pin functions conform to industry-standard flash memory addressing and control signaling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar parallel NOR flash memory applications.

Compared with MX29LV200CTTI-70G and S29AL016J70TFI020, the SST39VF020-70-4I-WHE-T provides integrated VPP generation and dual-status polling (DQ6/DQ7), reducing BOM count and simplifying firmware development - critical for cost-sensitive industrial designs requiring rapid field updates.

Availability

SST39VF020-70-4I-WHE-T is available at Aetrix Electronics and suitable for industrial control systems, medical diagnostics equipment, automotive body electronics, and smart utility metering requiring stable component supply across extended product lifecycles.

Supply support for SST39VF020-70-4I-WHE-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 the SuperFlash® portfolio for high-reliability, low-power nonvolatile memory solutions.

The SST39VF series was designed specifically for cost-sensitive, industrial-grade embedded applications requiring robust firmware storage with single-supply simplicity and long-term data integrity - leveraging SST's patented split-gate flash architecture.

FAQ

What is the maximum operating frequency supported by SST39VF020-70-4I-WHE-T?

The SST39VF020-70-4I-WHE-T does not specify a maximum clock frequency because it is an asynchronous parallel NOR flash. Its timing is governed by absolute parameters: 70 ns read cycle time (TRC), 40 ns minimum WE#/CE# pulse width, and 0 ns address setup/hold. System bus speed is determined by these values - e.g., a 70 ns TRC supports up to ~14.3 MHz effective throughput in continuous read mode. The SST39VF020-70-4I-WHE-T datasheet confirms this in Table 12.

Does SST39VF020-70-4I-WHE-T support both CE#- and WE#-controlled write operations?

Yes, the SST39VF020-70-4I-WHE-T fully supports both CE#- and WE#-controlled command sequences for Byte-Program, Sector-Erase, and Chip-Erase operations. Figures 5 and 6 in the DS25023B datasheet show identical timing waveforms for both control methods, and the text states "WE# and CE# signals are interchangeable as long as minimum timings are met." This dual-control flexibility simplifies integration with diverse microcontroller bus interfaces. The SST39VF020-70-4I-WHE-T implements this at silicon level.

What is the purpose of the AMS pin in SST39VF020-70-4I-WHE-T, and how is it assigned?

AMS (Address Most Significant) is not a dedicated pin but denotes the highest-order address line used for sector selection: for SST39VF020-70-4I-WHE-T, AMS = A17. During Sector-Erase, A17–A12 select the target 4 KB sector; during Block-Erase (not supported on this device), A17–A16 would apply. This mapping is explicitly defined in Table 1 and Figure 3 of the DS25023B datasheet. The SST39VF020-70-4I-WHE-T uses A17 as AMS to address its 256K × 8 array with 64 uniform sectors.

How does SST39VF020-70-4I-WHE-T handle power-up sequencing to prevent spurious writes?

The SST39VF020-70-4I-WHE-T incorporates three hardware protections: (1) VDD power-up/down detection inhibits writes below 1.5 V; (2) noise/glitch protection ignores WE#/CE# pulses <5 ns; and (3) Write Inhibit Mode activates when OE# is low, CE# is high, or WE# is high. These features ensure no unintended program/erase occurs during power ramp-up or brown-out. Table 8 and Section "Hardware Data Protection" in DS25023B confirm these mechanisms for the SST39VF020-70-4I-WHE-T.

Is SST39VF020-70-4I-WHE-T RoHS compliant and lead-free?

Yes, the SST39VF020-70-4I-WHE-T is RoHS compliant and lead-free. The DS25023B datasheet states "All devices are RoHS compliant" on page 1, and the "WHE-T" suffix denotes a lead-free, halogen-free, 32-lead TSOP package per Microchip's packaging nomenclature. The device meets JEDEC J-STD-020 moisture sensitivity level 3 and qualifies for Pb-free reflow at 260°C for 10 seconds, as specified in Table 11 of the datasheet.