| 摘要 |
PURPOSE:To reduce the power loss of the power amplifier circuit by driving the first-step amplification part of the power amplfier circuit with the DC power supply from the rectifier circuit and then driving the final-step power part with the output of the AC stable power circuit. CONSTITUTION:First-step amplification part 104 of power amplifier circuit 102 is driven by the DC voltage obtained by rectifying 101 the voltage of power transformer 2; while the final-step power part 105 of circuit 102 is driven with the output voltage of AC stable power circuit 103. Reference voltage supply terminals 12a and 12b of circuit 103 receive supply of the input signal of circuit 102, the output signal featuring the analogous relation to the input signal, the feedback signal or the signal extracted from an optional point of circuit 102, thus controlling the output of circuit 102. Accordingly, the output of circuit 103 features the DC voltage of circuit 101 piled on with the voltage proportional the input signal of circuit 102, and absorbs the fluctuation of the power voltage through circuit 103. Thus the fixed voltage can always be supplied to power part 105. As a result, the power consumption is reduced at circuit 103 to maintain a high fidelity of the signal amplification and then to reduce the cost of the overall power amplification. |
