An output amplifier includes a differential stage having a reference voltage supplied to a first input, a first output stage that receives an output of the differential stage, a second output stage whose output is connected to a load, a capacitor element having a first end connected to a second input of the differential stage, and connection control circuits that control switching of first and second connection modes. In the first connection mode, there are provided a non-conductive state between output of the differential stage and input of the second output stage, a non-conductive state between output of the first output stage and output of the second output stage, a conductive state between output of the first output stage and the second input of the differential stage, and voltage of a second end of the capacitor element is an input voltage from the input terminal. In the second connection mode, there are provided a conductive state between output of the differential stage and input of the second output stage, a conductive state between output of the first output stage and output of the second output stage; a non-conductive state between output of the first output stage and the second input of the differential stage, a non-conductive state of the second end of the capacitor element from the input terminal, and a conductive state between the output of the first output stage and the second end of the capacitor element.