| 摘要 |
PROBLEM TO BE SOLVED: To provide a solder pad which is formed on a printed wiring board and to which a plurality of outer leads of a surface mounted electronic component are soldered, which can prevent solder bridges from being generated between adjacent solder pads and can sufficiently exhibit its self-alignment function when the solder is melted. SOLUTION: The solder pads 2 formed in a plurality of number continuously with circuit patterns 3 on the printed board 1 are formed in a taped shape wherein the width is gradually reduced in the longitudinal direction from an outer edge 2a toward an inner edge 2b. In a reflow process, molten solder tends to concentrate on a solder fillet on the lower side of an outer lead due to the capillary phenomenon, easily causing solder bridges. However, the width of the inner edge 2b corresponding to the lower side of the outer lead is narrowed to a size (h) of the width of the outer lead, causing the solder to be dispersed. Consequently, the solder never overflows the solder pad 2 region and therefore there is no generation of solder bridges between the adjacent solder pads.
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