As illustrated in FIGS. 2 and 3A, a power system wiring pattern P1p having a relatively large area and a plurality of signal system wiring patterns P1s are formed in the first layer 10a. In this example, since current flows in the Y-axis direction in FIG. 3A, an electric power system wiring pattern P1p is formed such that the width in the X-axis direction is sufficiently large. Accordingly, the electric resistance of the electric power system wiring pattern P1p can be reduced. The pattern width of the electric power system wiring pattern P1p is uniformly formed from one end to the other end in the Y-axis direction.

The plurality of signal system wiring patterns P1s on the first layer 10a are each disposed at a position slightly separated from the electric power system wiring pattern P1p. Therefore, the signal system wiring pattern PIs and the electric power system wiring pattern P1p are electrically insulated from each other by the insulator 11. Since a relatively small current flows through each of the signal system wiring patterns P1s, these pattern widths do not need to be as large as the electric power system wiring pattern P1p. Incidentally, in the configuration example of FIG. 1, each of the signal system wiring patterns P1s of the first layer 10a is not a protection target with respect to the induction magnetic field.