Operational amplifier circuits

An operational amplifier circuit, comprising:

• a first stage amplifier circuit, coupled to a first input node and a second input node for receiving a first input signal and a second input signal, amplifying the first input signal to generate a first amplified signal and amplifying the second input signal to generate a second amplified signal;
• a second stage amplifier circuit, coupled to the first stage amplifier circuit for receiving and amplifying the first amplified signal and the second amplified signal to generate a first output signal at a first output node and a second output signal at a second output node, wherein the second stage amplifier circuit comprises:
• a first transistor, coupled between an operating voltage and the first output node;
• a second transistor, coupled between the first output node and a ground;
• a third transistor, coupled between the operating voltage and the second output node;
• and
• a fourth transistor, coupled between the second output node and the ground;
• a first feedforward circuit, directly connected to the first input node and a gate of the second transistor for feeding the first input signal forward to the gate of the second transistor;
• and
• a second feedforward circuit, directly connected to the second input node and a gate of the fourth transistor for feeding the second input signal forward to the gate of the fourth transistor.