Winbond Electronics Corporation W25Q64FWSSIG

Overview

W25Q64FWSSIG from Winbond is a 1.8V, 64M-bit (8MB) serial NOR flash memory with Dual/Quad SPI and QPI interfaces, organized as 32,768 × 256-byte pages. It supports 104MHz SPI clock, 416MHz equivalent Quad I/O transfer rate, and true execute-in-place (XIP) operation via Continuous Read Mode. Used for code storage, firmware boot, and parameter retention in space-constrained embedded systems.

For engineers reviewing the W25Q64FWSSIG datasheet, W25Q64FWSSIG pinout, W25Q64FWSSIG application, or W25Q64FWSSIG equivalent, key selection criteria include 1.65–1.95V supply compatibility, 4KB uniform sector erase granularity, Quad Enable (QE) bit configuration, /HOLD or /RESET dual-function pin behavior, and JEDEC-compliant SFDP register support.

Technical Context

The W25Q64FWSSIG implements a flexible SPI command architecture supporting Standard (4-wire), Dual (2 I/O lines), Quad (4 I/O lines), and QPI (2-clock instruction fetch) modes - all sharing identical physical pins with mode-dependent function mapping. Its status register set includes volatile/non-volatile BP2–BP0, TB, SEC, CMP, SRP0/SRP1, QE, and HOLD/RST bits that govern protection, interface behavior, and pin functionality.

Memory organization features uniform 4KB sectors (4,096 total), 32KB and 64KB blocks (256 total), and chip-erase capability. Erase/program suspend/resume, 64-bit unique ID, three 256-byte security registers with OTP locks, and SFDP register enable standardized configuration discovery and secure firmware updates.

Key Specifications

Pinout & Package

W25Q64FWSSIG uses an 8-pin SOIC 208-mil package (Package Code SS), with lead-free, RoHS-compliant construction and operating temperature range of –40°C to +85°C.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MX25L6433FZNI-10G and S25FL064L0XMFI001, the W25Q64FWSSIG delivers higher SPI bandwidth, standardized SFDP-based configuration, and QPI mode for reduced instruction overhead - making it optimal for resource-constrained XIP and OTA applications where 1.8V operation is required.

Availability

W25Q64FWSSIG is available at Aetrix Electronics and suitable for bootloader storage, firmware OTA updates, industrial HMI configuration, and automotive telematics log buffering requiring stable component supply, long-lifecycle availability, and RoHS-compliant packaging.

Supply support for W25Q64FWSSIG 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

Winbond Electronics is a Taiwan-based semiconductor company specializing in specialty DRAM, mobile DRAM, and serial flash memory solutions for consumer, industrial, and automotive markets.

The W25Q64FWSSIG belongs to Winbond's W25Q family of high-performance serial NOR flash devices, designed specifically for code execution, firmware storage, and secure parameter retention in space- and power-constrained embedded systems.

FAQ

What is the supply voltage range supported by the W25Q64FWSSIG?

The W25Q64FWSSIG operates from 1.65 V to 1.95 V. This narrow 1.8V nominal range eliminates the need for external level shifters when interfacing with 1.8V microcontrollers or FPGAs, simplifies power design, and reduces standby current to <1 µA. Operation outside this range may cause unreliable read/write behavior or permanent damage.

Does the W25Q64FWSSIG support execute-in-place (XIP) operation?

Yes, the W25Q64FWSSIG supports true XIP via its Continuous Read Mode, which requires only 8 clocks to initiate memory access and enables efficient sequential reads. Combined with Quad SPI or QPI modes, it delivers up to 416 MB/s effective throughput - sufficient for running application code directly from flash in many Cortex-M and RISC-V systems without loading into RAM first.

How does the /HOLD pin function differ between Standard SPI and Quad SPI modes on the W25Q64FWSSIG?

In Standard SPI mode (QE = 0), the /HOLD pin pauses ongoing operations while /CS is low, placing DO in high-impedance state. In Quad SPI mode (QE = 1), the same physical pin becomes IO3 and is used for bidirectional data transfer - disabling the hold function entirely. The pin's role is determined solely by the QE bit in Status Register-2.

What security features does the W25Q64FWSSIG provide beyond basic write protection?

Beyond /WP pin and status register BP bits, the W25Q64FWSSIG includes three 256-byte OTP-lockable security registers, a 64-bit unique serial number per device, JEDEC-standard SFDP register for safe configuration discovery, and individual sector/block lock/unlock commands (36h/39h). These enable secure key storage, anti-cloning, and field-upgrade-safe firmware partitioning.

Can the W25Q64FWSSIG be used as a drop-in replacement for older W25Q64FV or W25Q64BV devices?

No - the W25Q64FWSSIG is not a pin-compatible or functional drop-in replacement for W25Q64FV or W25Q64BV. It introduces new features including QPI mode, enhanced security registers, and revised status register bit definitions (e.g., QE location). Migration requires firmware updates to configure QE, verify status register behavior, and validate timing margins under 104MHz operation.