VARIABLE ATTENUATOR AND MOBILE COMMUNICATION DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a small-sized variable attenuator capable of continuously and variably controlling an attenuation amount. SOLUTION: This variable attenuator 10 is provided with a comb line 13 composed of lines 11 and 12 electromagnetically coupled by a coupling degree M and diodes D1 and D2 connected to the lines 11 and 12 for forming the comb line 13. One end of a conductor 11 is grounded through a capacitor C1 and connected through the capacitor C2 to an input terminal Pi. Also, the diode D1 is connected between the other end of the conductor 11 and the ground and connected through a resistor R1 to a control terminal Vc1. One end of the conductor 12 is grounded through the capacitor C3 and connected through the capacitor C4 to an output terminal Po. Also, the diode D2 is connected between the other end of the conductor 12 and the ground and connected through the resistor R2 to the control terminal Vc2.