| 摘要 |
<p>According to embodiments of the present invention, an over-input signal may be limited to be within a range between adjustable upper limit voltage and lower limit voltage while suppressing deterioration of a noise figure. An amplifier circuit includes an input transistor; an input transistor; a resistor element having a first terminal connected to a gate of the input transistor and a second terminal connected to a bias voltage; and a protective circuit connected to the gate of the input transistor and limiting an input to the gate of the input transistor to be within a range between an upper limit voltage and lower limit voltage adjustable based on the bias voltage.</p> |
