I’m designing a 4-layer PCB with FR4 material and a thickness of 1.6mm. The PCB includes ICs with 0.5mm pitch pads and LEDs with 0.4mm pitch pads, which are quite small. I’m puzzled whether to go with ENIG, despite its higher cost, or if HASL would suffice for my needs. I’ve come across information suggesting that ENIG is crucial for BGA applications, but I’m unsure about the pitch limit for QFN where HASL would still be acceptable.
I would recommend ENIG but HASL should work fine as well.
ENIG will be preferred. I doubt that lead free HASL will be flat enough.
Alternate finishes might be silver (tarnish risk) or OSP (limited assembly processing cycles).
1 Like