| 摘要 |
PURPOSE:To assemble a bias circuit section or the like onto the same circuit board together with an amplifier circuit section while suppressing the waveguide mode by standing a shield plate to separate the amplifier circuit section from other circuit sections like the bias circuit section or the like. CONSTITUTION:A dielectric circuit board 11 is divided by the conductor shield plate 20 into a part on which the amplifier circuit section including a strip line 13 is constituted and a part constituted with the bias circuit 15. The shield plate 20 penetrates through the board 11 and the board 11 is divided into two parts also in terms of high frequency. A high-frequency current flows to the line 13, the cutoff frequency depends on an interval B between the shield plate 20 and a side wall 16a of a metallic case 16, and since the interval B is only the width of the amplifier circuit, a high cutoff frequency is obtained, thereby suppressing easily the waveguide mode. |
