99-WLCSP — footprint and assembly considerations
The CY8C5488FNI-LP212T comes in a 99-ball WLCSP (5.19 x 5.94 mm). This ultra-compact package saves board area but demands a controlled assembly process: the 0.4 mm ball pitch requires a solder mask defined pad and a stencil aperture sized for consistent solder volume. The 62 I/O are distributed across the array, so fan-out vias need to be placed between balls. A four-layer PCB with a solid ground plane under the package helps with both signal integrity and thermal spreading. The part is ROHS3 compliant, and the MSL rating should be confirmed from the latest Infineon packing label — WLCSP devices are typically MSL 1 or 3.
Infineon lists the CY8C5488FNI-LP212T as Active. For dual-sourcing or a higher-performance option within the same ecosystem, the PSoC 6 CY8C6137BZI-F54 (Cortex-M4, 150 MHz) is a pin-compatible alternative worth evaluating, though it carries a different peripheral set and memory map.