| 摘要 |
PURPOSE:To obtain a board possible for miniaturization while having excellent input output isolation by providing three or more ground layers among four or more dielectric layers and using a strip line between ground layers for an input side circuit and using a strip line between different ground layers for an output side circuit. CONSTITUTION:Ground layers 3-5 are formed among dielectric layers 6-11. Strip lines 1, 2 are respectively separated by the ground layers 3, 4 and connected to electrodes 14, 15 of a semiconductor element 16 through via-holes 12, 13. When the line 1 is used for an input side of a high frequency amplifier circuit and the line 2 is used for an output side, the oscillation due to direct propagation of the signal between the input side circuit and the output side circuit hardly takes place. Furthermore, it is not required to increase the distance between the lines 1 and 2 and miniaturization is attained. |
