Patent ID: 6380808
Filing Date: 2002-04-30
Classification: H03F

Abstract:
A push-pull amplifier circuit comprising:a push-pull output circuit having first and second transistors (11 and 10) connected in series between first and second power supply potentials, a conductivity of said second transistor being opposite to that of said first transistor, each of said first and second transistors having a control input; a control input potential difference circuit (16A) having first and second ends (OP and ON) being connected to said control inputs of said first and second transistors and a control input for receiving a control signal (VG3) to adjust a voltage between said first and second ends in response to said control signal, said control signal being generated on the basis of an idle current that flows through said first and second transistors; and an input circuit (17) for changing potentials of said first and second ends in response to an input signal with keeping said voltage substantially constant.