It communicates over a Quad I/O SPI interface at up to 133 MHz, giving you fast read and program throughput for firmware storage, boot code, and OTA staging.
Quad I/O at 133 MHz — what the bus speed buys you
Quad I/O means four data lines instead of one, so a single 133 MHz clock cycle transfers four bits. For a 256 Mbit device, that translates to read throughput well above 50 MB/s in fast-read mode. If your MCU boots from this Flash or you stream large look-up tables, the Quad I/O interface cuts the time the bus is busy, freeing the host for other tasks. The 133 MHz clock is the rated maximum; your host SPI controller must support that speed to get the full bandwidth.
16-SOIC wide-body — rework-friendly footprint
The 16-SOIC (0.295", 7.50 mm width) package is a standard wide-body SOIC. The leads are visible and accessible, so hand rework with a hot-air station is straightforward — no underfill, no hidden balls. The 1.27 mm pitch gives good clearance for routing and probing.
The FL-S series is a mature, widely used NOR Flash family, and the active status reflects continued manufacturing support.