| 摘要 |
<p>A class D amplifier capable of stabilizing the power supply voltage and reducing the power consumption. A class D amplifier includes field effect transistors (Q1,Q2) that generate an output signal (Sout) by switching, based on modified signals of rectangular waveform, voltages supplied through power supply lines (P1,P2) connected to a power supply circuit (11) that outputs power supply voltages (+Vs,-Vs). The class D amplifier further includes voltage detecting parts (16p,16g) that determines whether the voltages of the power supply lines (P1,P2) deviate from the power supply voltages (+Vs,-Vs) due to occurrence of an offset in the output signal (Sout) and that, when detecting a voltage deviation, generate detection signals (Dp,Dg). The class D amplifier still further includes current control parts (17p,17g) that reduce or increase, in response to the generation of the detection signals (Dp,Dg), the currents following through the power supply lines (P1,P2), thereby maintaining the voltages of the power supply lines (P1,P2) at the power supply voltages (+Vs,-Vs).</p> |
