Driver circuit and operational amplifier circuit used therein

A driver circuit, comprising:

• a first operational amplifier circuit, comprising:
• a first input stage circuit, for receiving a first input signal and amplifying the first input signal to generate a first amplified signal;
• and
• a first output stage circuit, for generating a first output signal;
• a second operational amplifier circuit, comprising:
• a second input stage circuit, for receiving a second input signal and amplifying the second input signal to generate a second amplified signal;
• and
• a second output stage circuit, for generating a second output signal;
• and
• a power switching circuit, coupled to the first input stage circuit and the second input stage circuit, the power switching circuit comprising:
• a first output terminal, for outputting one of the first amplified signal and the second amplified signal in response to a control signal;
• and
• a second output terminal, for outputting the other of the first amplified signal and the second amplified signal in response to the control signal;
• wherein the first output stage circuit is coupled to the first output terminal of the power switching circuit, the second output stage circuit is coupled to the second output terminal of the power switching circuit, and the power switching circuit is configured to switch a first power supply for both the first input stage circuit and the second input stage circuit between a first supply voltage and a second supply voltage in response to the control signal.