| 摘要 |
PURPOSE:To attain high density packaging of a circuit for this receiver and to avoid increase in the stray capacitance in a high frequency circuit section by adopting the wiring layers of a multilayer wiring board in the high frequency circuit section with at least an interval of one or more layer. CONSTITUTION:Only a wiring layer between an upper face of a 1st board layer 30a and a lower face of a 3rd board layer 30c is utilized at a part of a multilayer wiring board 30 in which an analog circuit section 1 processing a high frequency signal is mounted and no wiring pattern 34 is provided to the wiring layer inbetween. Thus, the vertical interval of the wiring pattern 34 is taken sufficiently. Thus, the stray capacitance is small and noise based thereby is much less and since the wiring pattern 34 is arranged in a digital section 16 by utilizing all the wiring layers, high density packaging of the circuit section is attained and the radio receiver is miniaturized. |
