256 Mbit NOR flash for code-shadowing and XIP
The Infineon S25FL256LAGNFN013 is a 256 Mbit SPI NOR flash from the FL-L series, organized as 32M x 8 bits. The 133 MHz quad-I/O interface delivers a sustained read throughput that supports execute-in-place (XIP) for microcontrollers that cache instructions from external flash — the 133 MHz clock rate means the SPI bus can keep up with a Cortex-M core fetching at moderate clock speeds without wait-state penalties. NOR flash provides the fast random-access latency required for direct code execution, unlike NAND which demands page-buffering and ECC overhead.
Temperature grade and package thermal path
At 125°C, NOR flash retention is a temperature spec — the FL-L series is designed for 20-year data retention at the rated maximum, but the actual retention window shrinks with temperature; budget the ECC or wear-leveling if the part sees sustained 125°C operation with frequent erase cycles. The exposed pad should be soldered to a copper plane — floating it leaves the die temperature rise uncontrolled during continuous quad-I/O reads at 133 MHz.
Active lifecycle and supply posture
No official cross-reference or pin-compatible second-source is listed on the record — the FL-L series is the Infineon production baseline for this density and interface.