Winbond Electronics Corporation W25Q40BWSSIG TR

Overview

W25Q40BWSSIG TR from Winbond is a 1.8V 4M-bit serial NOR flash memory IC supporting Standard, Dual, and Quad SPI interfaces. It delivers 40MB/s continuous read throughput, features uniform 4KB sector erase architecture, 128 sectors/8 blocks, and operates across -40°C to +85°C with 4mA active and <1µA power-down current - deployed in microcontroller boot code storage and firmware update storage for space-constrained embedded systems.

For engineers reviewing the W25Q40BWSSIG TR datasheet, W25Q40BWSSIG TR pinout, W25Q40BWSSIG TR application, or W25Q40BWSSIG TR equivalent, key selection criteria include Quad SPI XIP capability, hardware write protection via /WP and /HOLD pins, JEDEC ID and 64-bit unique serial number support, and compatibility with 1.65–1.95V supply rails in SOIC-8 (150-mil) packaging.

Technical Context

The W25Q40BWSSIG TR implements a SPI command set compliant with Modes 0 and 3, enabling standard, dual-output, and quad-I/O operations. Its internal architecture includes a 256-byte page buffer, status register-1 (with BUSY, WEL, BP2–BP0, TB, SEC, CMP, SRP1/SRP0, SUS) and status register-2 (with QE, LB3–LB0), where Quad Enable (QE) must be set non-volatily to activate IO2 (/WP) and IO3 (/HOLD) for full Quad SPI functionality.

It supports four distinct erase granularities - 4KB sector, 32KB block, 64KB block, and chip erase - and enables Erase/Program Suspend & Resume for real-time interrupt handling during flash operations. The device integrates hardware write protection logic tied to /WP pin state and configurable software lock bits, with security registers (4×256-byte) featuring OTP locks for secure parameter storage.

Key Specifications

Pinout & Package

W25Q40BWSSIG TR is packaged in 8-pin SOIC-150-mil (package code SN), with 1.27mm pitch and standard JEDEC MS-012AC footprint. Pin functions are electrically identical across SOIC, VSOP, WSON, and USON variants per datasheet Figure 1a/1b.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AT25SF041-SSHD-B and MX25L4006EM1I-12G, the W25Q40BWSSIG TR uniquely combines 1.8V operation, Continuous Read Mode for XIP efficiency, and factory-programmed 64-bit UID - making it optimal for next-generation ultra-low-power, secure, and boot-critical embedded applications.

Availability

W25Q40BWSSIG TR is available at Aetrix Electronics and suitable for MCU boot code storage, firmware OTA updates, and IoT sensor configuration storage requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for W25Q40BWSSIG TR 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 memory solutions, including SPI NOR/NAND flash, PSRAM, and audio codecs, serving industrial, automotive, and consumer markets since 1987.

The W25Q series is designed specifically for high-performance, low-voltage embedded systems requiring fast code execution, robust data retention, and hardware-assisted security - targeting applications where space, power, and reliability constraints preclude use of parallel flash.

FAQ

What is the operating voltage range of the W25Q40BWSSIG TR?

The W25Q40BWSSIG TR operates from 1.65V to 1.95V, making it compatible with 1.8V logic systems without level shifters. This narrow rail reduces power consumption and simplifies power supply design. The device enters reset below 1.65V and requires tPUW delay before accepting write commands after VCC exceeds threshold. All timing parameters in the datasheet are specified within this range.

Does the W25Q40BWSSIG TR support execute-in-place (XIP) operation?

Yes, the W25Q40BWSSIG TR supports true XIP via Continuous Read Mode and Fast Read Quad I/O (EBh) instructions. With as few as 8 clock cycles overhead per 24-bit address and 320MHz effective bandwidth in Quad mode, it enables direct code execution from flash - eliminating RAM copy latency and reducing system memory footprint. XIP performance is validated across -40°C to +85°C.

How many erase sectors and blocks does the W25Q40BWSSIG TR have?

The W25Q40BWSSIG TR contains 128 uniform 4KB sectors and 8 uniform 64KB blocks. Sector erase (20h) targets individual 4KB regions, while block erase (D8h) clears 64KB chunks. The array also supports 32KB block erase (52h). This hierarchical structure allows flexible firmware partitioning - e.g., dedicating sectors to bootloader, app image, and config data - without erasing unrelated regions.

What is the purpose of the /WP and /HOLD pins on the W25Q40BWSSIG TR?

The /WP pin provides hardware-level write protection for the status register, preventing accidental BP bit changes when pulled low. The /HOLD pin pauses active SPI transactions while /CS remains asserted - useful when sharing bus lines with other peripherals. Both functions are disabled during Quad SPI operation (when QE=1), as /WP and /HOLD become IO2 and IO3. Their active-low behavior is defined in Sections 5.4 and 5.5 of the datasheet.

Is the W25Q40BWSSIG TR pin-compatible with other W25Q-series flash devices?

Yes, the W25Q40BWSSIG TR shares identical pinout, package dimensions, and electrical interface with other W25Qx0BW variants in SOIC-150-mil (SN), VSOP (SV), WSON (ZP), and USON (UX) packages. Signal mapping (e.g., /CS, CLK, DI/DO, /WP, /HOLD, VCC, GND) and AC/DC timing are consistent across the family - enabling scalable memory sizing without PCB redesign.