Operational amplifier with controllable output modes

A circuit for at least partially tracking an input signal, comprising:

• a differential input circuit comprising an output and a differential input transistor pair having inputs coupled to a differential signal;
• a first multiplexer having a first input coupled to a supply voltage, a second input coupled to the output of the differential input circuit, a third input coupled to a supply common return and an output coupled to an input of a first output transistor;
• a second multiplexer having a first input coupled to the supply voltage, a second input coupled to the output of the differential input circuit, a third input coupled to the supply common return and an output coupled to an input of a second output transistor;
• the first and second output transistors are totem pole configured with an output therebetween, wherein the first output transistor is coupled to the supply voltage and the second output transistor is coupled to the supply common return;
• and
• a control circuit coupled to the first and second multiplexers for selecting the inputs thereof, wherein the first and second multiplexers are independently controlled by the control circuit;
• wherein selection of a certain combination of the first and second multiplexer inputs determines what part of the signal is tracked.

A method for configuring operation of an operational amplifier output, said method comprising the steps of:

• providing a differential input circuit comprising an output and a differential input transistor pair having inputs coupled to a differential signal;
• providing a first multiplexer having a first input coupled to a supply voltage, a second input coupled to the output of the differential input circuit, a third input coupled to a supply common return and an output coupled to an input of a first output transistor;
• providing a second multiplexer having a first input coupled to the supply voltage, a second input coupled to the output of the differential input circuit, a third input coupled to the supply common return and an output coupled to an input of a second output transistor;
• and
• selecting inputs of the first and second multiplexers independently from each other to configure operation of the first and second output transistors.