Description

A designed experiment evaluated the influence of several variables on appearance and strength of Pb-free solder joints. Components with leads finished with nickel-palladium-gold (NiPdAu) were used from Texas Instruments (TI) and two other integrated circuit suppliers. Pb-free solder paste used was tin-silver-copper (SnAgCu) alloy. Variables were printed wiring board (PWB) pad size/stencil apertu