| 摘要 |
<p>An excellent power amplifier having a power amplifier which is used for various kinds of acoustic apparatus and the distortion factor of the output of which is not deteriorated under any condition by controlling a voltage-controlled amplifier in accordance with the fluctuation of the input signal and the power supply voltage. The power amplifier device is provided with a limiter means in which a signal taken out from the node between a voltage amplifier (3) and a power amplifier (5) is fed to a voltage comparator (7), the output of the voltage comparator (7) is converted into a dc voltage by an integrating circuit (8), and the amplification degree of a voltage-controlled amplifier (2) is changed by the dc voltage, thereby performing voltage limiting in accordance with the output state of the power amplifier (5), and fixing the distortion factor of the output voltage.</p> |
