Patent ID: 8164388

Claim:
An amplifying apparatus for amplifying an input signal supplied to an input terminal and outputting an output signal from an output terminal, the amplifying apparatus comprising: a high-potential power supply line through which a high voltage is supplied; a low-potential power supply line through which a low voltage is supplied; a power supply in which one of the high voltage and the low voltage is a fixed voltage that is externally supplied, and which generates, as the other of the high voltage and the low voltage, one of a first voltage in which, based on the fixed voltage, a polarity of the fixed voltage is inverted with reference to a ground potential, and a second voltage which is closer to the ground potential than the first voltage is; an outputting section which has a p-channel transistor that is source-grounded to the high-potential power supply line and that is connected to the output terminal, and an n-channel transistor that is source-grounded to the low-potential power supply line and that is connected to the output terminal; an amplifying section which amplifies the input signal, and which supplies the amplified input signal to a gate of the p-channel transistor and a gate of the n-channel transistor; and a control unit which controls the power supply to cause the other of the high voltage and the low voltage to be switched between the first voltage and the second voltage in accordance with a signal level of the output signal.