MT25QL256ABA1EW9-0SIT

The MT25QL256ABA1EW9-0SIT is a high-performance 256-Mbit (32-MB) serial NOR Flash memory device from Micron Technology, part of the second-generation MT25Q family. It combines high-speed serial interface performance with advanced feature set in a compact WPDFN-8 package. The device supports standard SPI as well as dual and quad I/O protocols, enabling data transfer rates up to 90 MB/s at 133 MHz clock frequency in quad I/O mode. Both Single Transfer Rate (STR) and Double Transfer Rate (DTR) modes are supported. The memory array is organized into uniform 64KB sectors, with 4KB and 32KB subsector granularity available for flexible erase operations. Each sector supports a minimum of 100,000 erase cycles with 20 years typical data retention. Execute-in-place (XIP) functionality allows code to be executed directly from Flash without needing to copy to RAM first, reducing system memory requirements and boot time. The device includes advanced security features including 64 bytes of OTP (One-Time Programmable) memory, volatile and non-volatile sector locking, password protection, and hardware write protection. A CRC detection mechanism helps identify accidental data corruption. The ‘A’ in the part number indicates monolithic device stacking, ‘BA’ indicates second generation with die revision A, ‘E’ signifies 64KB sector size with RESET#/HOLD# pin configuration, ‘W9’ specifies the 8x6mm W-PDFN package, ‘0’ indicates standard security, and ‘SIT’ denotes the industrial temperature range (-40°C to +85°C).

The MT25QL256ABA1EW9-0SIT operates as a serial NOR Flash memory device using an SPI-compatible interface. The memory cell structure is based on floating-gate NOR Flash technology, where each memory cell stores a charge on a floating gate to represent data. NOR Flash provides random access reads with short initial access latency, making it ideal for code storage and execute-in-place applications. Operation follows a command-based protocol: the host controller sends an instruction byte over the SPI interface followed by address bytes (where required) and data bytes (for write operations). Common commands include READ (03h), Fast READ (0Bh), Quad Input Fast Program (32h), Sector Erase (D8h), and Write Enable (06h). The device supports three address modes: 1) Standard 3-byte addressing for up to 128Mb devices; 2) 4-byte addressing for densities beyond 128Mb (enabled via command or non-volatile register); 3) Extended address mode using an address extension register. Programming is performed on 256-byte pages, with each byte in a page able to be programmed from 1 to 0 (but not the reverse). Erasing resets all bytes in a sector/subsector to 1 (0xFF). The device supports Program Suspend and Erase Suspend operations, allowing a read operation to interrupt an ongoing program or erase operation temporarily. Write protection is implemented through multiple layers: status register block protect bits define which sectors are protected, the write protect pin (W#) can be used to prevent status register writes, and password protection adds an additional security layer. The 64-byte OTP area provides permanent, user-lockable non-volatile storage for unique identifiers or security keys.

• Boot code and firmware storage for embedded microprocessor systems
• Execute-in-place (XIP) code storage for low-cost systems
• FPGA configuration data storage
• Industrial control and automation equipment firmware
• Networking and telecommunications infrastructure
• Consumer electronics: set-top boxes, smart TVs, wearables
• IoT edge devices and smart home controllers
• Automotive infotainment and telematics systems