| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an amplification circuit that is configured to block a current flow to a CMOS LNA circuit while the CMOS LNA circuit is inoperative without increasing an NF. <P>SOLUTION: The amplification circuit provided includes: an input transistor having a gate electrode, a drain electrode and a source electrode connected with a signal input terminal for inputting a received radio signal, a power terminal and a ground terminal, respectively; a first switch disposed between the signal input terminal and the gate electrode of the input transistor; and a second switch disposed between the power terminal and the drain electrode of the input transistor. A predetermined bias voltage is applied to the gate electrode of the input transistor. For radio signal reception, the first switch and the second switch are simultaneously turned on. For radio signal transmission, the first switch and the second switch are simultaneously turned off with the predetermined bias voltage kept being applied to the gate electrode of the input transistor. <P>COPYRIGHT: (C)2013,JPO&INPIT |
