| 摘要 |
PROBLEM TO BE SOLVED: To provide a printed circuit board with less heat generation in wiring patterns. SOLUTION: A surface wiring pattern 2 is formed on the surface of an insulating board 1. A back wiring pattern 3 is formed plane-symmetrically with respect to the surface wiring pattern 2 on the back surface of the insulating board 1, facing the surface wiring pattern 2. Openings 10 are formed through the surface wiring pattern 2 and the back wiring pattern 3. Conductive material layers are provided on the inner walls of the openings 10. Solder 11 is placed into the opening parts 10, for example, and conductive filling parts are provided. Consequently, the surface wiring pattern 2 and the back wiring pattern 3 are securely and electrically connected. Thus, the current capacity and heat capacity of the wiring patterns become large and heat generation is reduced. |
