| 摘要 |
<p>A microwave circuit comprises a first amplifier circuit and a second amplifier circuit. The first amplifier circuit includes a first transistor having a base terminal to which a high frequency signal is applied and operating as a common-emitter amplifier, and is active in a first current mode. The second amplifier circuit having a substantially equivalent gain to that of the first amplifier circuit includes a second transistor having a base terminal which is connected to the base terminal of the first transistor and to which a high frequency signal is applied and a collector terminal connected to the collector terminal of the first transistor and operating as a common-emitter amplifier, and is active in a second current mode. Accordingly, the microwave circuit can switch between the first current mode of a low current and the second current mode of a high current without changing the gain.</p> |
