128 Mbit NOR flash for code shadowing and data logging
The Infineon S25FL128SAGBHIA00 is a 128 Mbit NOR flash memory from the FL-S series, organized as 16M x 8 bits. It uses the SPI Quad I/O interface, which means the controller can read four data bits per clock cycle — useful for fast code shadowing from flash to RAM at boot or for high-speed data logging where the bus isn't the bottleneck. With a 133 MHz clock frequency in Quad I/O mode, the effective read throughput can reach 532 MHz equivalent (four bits per cycle). This is enough to feed a Cortex-M based MCU executing from flash via XIP (eXecute In Place) without stalling the core on sequential instructions.
24-BGA package — rework and layout reality
Housed in a 24-ball TBGA (8x6 mm body), the S25FL128SAGBHIA00 uses a 0.80 mm ball pitch — tight enough to save board space but still hand-reworkable with a decent hot-air station and stencil. The 0.80 mm pitch means the PCB needs via-in-pad or micro-vias only if you route all signals on inner layers; a four-layer board with blind vias on the top layer can fan out the outer two rows without micro-vias.