MULTILAYER WIRING BOARD

PROBLEM TO BE SOLVED: To reduce both simultaneous switching noise and EMI noise in a multilayer wiring board, on which an electronic component operating at high speed is mounted. SOLUTION: In the multilayer wiring board 1, an electrode 9 for semiconductor-element connection is installed on the surface of an insulation board 2, an external electrode 8 is installed on the rear, and a power supply is supplied via an internal power supply or via built-in capacitors in which ground wiring layers 4 to 7 are formed, so as to be faced and arranged. In the board 1, the built-in capacitors are formed, in such a way that a plurality of built-in capacitors having different resonance frequencies in a range from the operating frequency band of a semiconductor element 10 up to a harmonic- component frequency band are connected in parallel, their synthetic impedance value, at an antiresonant frequency generated between the different resonance frequencies, is set at a prescribed value or lower, and at least one built-in capacitor has a capacitor electrode 12, which is arranged on the surface of the insulating board 2 facing the power supply or the ground wiring layer 4.