| 摘要 |
PURPOSE:To attain switching of a large input signal and to eliminate the need for other oscillating sources to obtain a high voltage, by rectifying a part of a high frequency input power and superimposing the result on a bias of a transistor for high frequency switch control. CONSTITUTION:A part of a high frequency input power applied to a terminal T1 is picked up at a directional coupler 29 and a negative voltage is picked up at a voltage multiplying rectifier consisting of diodes 21, 22, capacitors 25, 27 or diodes 23, 24 and capacitors 26, 28. This voltage is superimposed on a terminal voltage at P2, P3 and applied to PIN diodes 1, 2 via coils 14, 15. Thus, since the diode 1 is reverse-biased with a voltage summed with a voltage rectifying a part of the input high frequency signal in addition to a voltage at a terminal T4, a large input power can also be interrupted. Since this reverse voltage is obtained by detecting a part of an input power, other oscillating sources for high voltage generation are not required. |
