In a printed circuit board, a semiconductor including plural power supply
terminals and a semiconductor chip is mounted onto a mounting surface of
a printed wiring board, and a bypass capacitor for reducting a power
ground noise is provided. Another bypass capacitor, which is connected to
the bypass capacitor only within an IC chip is provided to inhibit the
power ground noise from causing not only a variation in timing of the IC
chip and a malfunction thereof but also a malfunction of another IC chip
and the generation of an EMI noise in a case where the power ground noise
propagates to a power supply side.