The Infineon S25FL128SAGNFV000 is a 128 Mbit (16 M x 8) NOR Flash memory from the FL-S series, built for code shadowing, data logging, and firmware storage in embedded systems. It uses a Quad SPI interface that clocks at 133 MHz, giving the read throughput needed to keep a high-speed MCU's QSPI controller fed without wait states.
What the Quad SPI clock means for your bus
The 133 MHz clock on the Quad SPI interface translates to a theoretical peak read throughput of about 66 MB/s in quad-output mode. That is fast enough to support execute-in-place (XIP) from a Cortex-M7 or a RISC-V core without stalling the instruction pipeline during tight loops. If your MCU's QSPI controller tops out at 104 MHz, the part still runs at that lower speed — the 133 MHz rating gives margin for signal-integrity loss across a longer PCB trace or through a connector.