An amplifier may include a first transistor. The amplifier may also include a second transistor coupled to the first transistor in an output stage of the amplifier. The amplifier may also include a level shift resistor coupled between a gate of the first transistor and a gate of the second transistor. The amplifier may further include a feedback bias circuit coupled to the gate of the first transistor and the gate of the second transistor through the level shift resistor. The feedback bias circuit may be configured to sense a common mode voltage of the output stage of the amplifier, and to compare the common mode voltage with a reference voltage to control a resistor bias current conducted by the level shift resistor.