BY25Q40BSSIG(R)

Memory IC Overview

The BY25Q40BSSIG(R) is a 4M-bit SPI NOR Flash memory manufactured by BYTe Semiconductor. It supports Standard, Dual, Quad SPI, and QPI interfaces with read speeds up to 108MHz (Fast Read Serial) and data transfer rates of 216Mbits/s (Dual I/O) and 432Mbits/s (Quad I/O). Operating on a single 2.7V to 3.6V supply, it features flexible architecture with 4KB sectors and 32/64KB blocks. Key specifications include a typical page program time of 0.6ms, sector erase time of 50ms, and endurance of 100k cycles. Available in SOP-8 and USON-8 packages, it operates across commercial and industrial temperature ranges.

Memory IC Feature Summary

• Supports multiple interface modes including Standard SPI, Dual SPI, Quad SPI, and QPI for optimized data throughput.
• Features comprehensive write protection mechanisms including hardware /WP control, software block protection, and OTP security registers.
• Enables Execute-In-Place (XIP) operations with continuous read capabilities and wrap functions.
• Includes programmable status register protection schemes such as power supply lock-down and one-time programmable locks.

Memory IC Applications

• Embedded systems requiring non-volatile code storage
• Consumer electronics firmware storage
• IoT devices needing low-power flash memory
• Industrial controllers utilizing XIP execution

Memory IC Procurement Notes

Verify the specific package suffix matches your PCB footprint requirements, as the BY25Q40BS series includes SOP-8 and USON-8 options. Confirm the temperature grade corresponds to your operational environment, as commercial and industrial variants exist within the same family. Ensure the ordering information aligns with the manufacturer's current revision standards to avoid compatibility issues with existing designs.

Memory IC Selection Notes

Select this component when a 4M-bit capacity is required with high-speed Quad I/O or QPI interface support. Consider the voltage range of 2.7V to 3.6V for system power rail compatibility. Evaluate the package size constraints against the available SOP-8 and USON-8 options. Verify that the required temperature range, whether commercial or industrial, is supported by the specific part variant selected for the application.

Memory IC Part Context

The BY25Q40BS belongs to the BY25Qxx series of SPI NOR Flash memories from BYTe Semiconductor. This series is designed for applications demanding reliable non-volatile storage with flexible interface options. The 4M-bit density positions it between smaller 1M/2M variants and larger 8M+ devices, offering a balance of capacity and performance for mid-range embedded storage needs.

Memory IC Replacement Considerations

Check for compatible parts within the BY25Qxx series with matching density and interface support. Verify pinout compatibility if substituting with different package types like WSON. Ensure electrical characteristics, particularly voltage ranges and speed grades, meet the original design specifications before implementing any cross-manufacturer alternatives.

Memory IC FAQ

How does the device handle the transition between SPI and QPI modes?

The device switches to QPI mode using the Enter QPI instruction (38h), which requires the Quad Enable (QE) bit in Status Register 2 to be set to 1. To return to standard operation, the Exit QPI instruction (FFh) is used.

What are the available memory protection methods?

The device offers software protection via Block Protect bits, hardware protection using the /WP pin, power supply lock-down, and One-Time Programmable (OTP) locks for permanent protection of status registers and security areas.