| 摘要 |
<P>PROBLEM TO BE SOLVED: To stabilize a pulse voltage applied to a drain of a FET for high frequency amplification. <P>SOLUTION: A MOS-FET Q1 is driven according to an output voltage of a driving power supply 11. Q1 is switched by a reference pulse signal b output from a pulse signal source 12, and when Q1 is on, Q1 is driven in an unsaturated state by a voltage resulting from a charge shifted from a capacitor C1. A pulse voltage available at a source electrode of Q1 switched is applied to a drain electrode as a driving voltage for a high frequency power FET Q2 for amplifying a high frequency signal supplied to a gate electrode. A pulse voltage d appearing at the drain electrode of Q2 is compared with the voltage of the reference pulse signal b in an operational amplifier OP2 and is fed back to a gate electrode of Q1. The feedback to Q1 driven in the unsaturated state can prevent a drop in pulsed drain voltage applied to Q1. <P>COPYRIGHT: (C)2012,JPO&INPIT |
