| 摘要 |
PURPOSE:To obtain an amplifier circuit in which a maximum output voltage in matching with fluctuation in a power supply voltage and a load so as to minimize the power loss at an output stage thereby improving the efficiency. CONSTITUTION:When a power supply voltage +Vcc is higher than a voltage being the sum of a prescribed voltage Vref to an absolute value of a load voltage Vout, a gain control circuit 7 is operated at a prescribed gain with a comparison output from a comparator CP1. However, when the power supply voltage +Vcc is equal to the voltage being the sum of the prescribed voltage Vref to the absolute value of the load voltage Vout, the gain of the gain control circuit 7 is decreased by the comparison output from the comparator CP1 and the maximum output voltage of a load 5 is limited. |
