Provided is an output amplifier having: a push-pull output-stage formed by first and second output-stage transistors; and a detection circuit detecting an abnormal output current output by the output amplifier and including: a coupling circuit, generating first and second currents mirroring current flowing in the first output-stage transistor and third and fourth currents mirroring current flowing in the second output-stage transistor, coupling the first and third currents at a first output node, outputting a first voltage at the first output node, coupling the second and fourth currents at a second output node, and outputting a second voltage at the second output node; and a determination circuit, outputting a determination signal indicating normality of an output current based on the first and second voltages. The coupling circuit generates the first to fourth currents. In the reference state, the third current >the first current, the second current >the fourth current.