| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a circuit board capable of suppressing sulfurization reaction and silver migration on a soldering pad portion and improving reliability of soldering of a surface mounted component. <P>SOLUTION: A circuit board comprises: a module substrate; wiring patterns 25 and 26 mainly made of silver; an electrically insulated protection layer 37; a capacitor 65 having a pair of electrodes 67; and solder. The protection layer 37 is provided on soldering pad portions 25d and 26f and an intermediate pad 27 that are connected to the wiring patterns. The protection layer 37 has slot-shaped openings 37a and 37b, and four corners of these openings are formed in a circular arc shape or in an oblique shape. A capacitor 65 is disposed in the openings across the soldering pad portions. Solder is blocked by the edges of the openings 37a and 37b and covers the whole surface of the soldering pad portions. The electrodes are soldered to pad portions 25d, 26f, and 27 with the solder. <P>COPYRIGHT: (C)2012,JPO&INPIT |
