A semiconductor apparatus operates based on a first voltage, a second voltage lower than the first voltage, and a third voltage in between the first and second voltages, and includes an output circuit including at least one transistor where a signal having an amplitude ranging from the second to first voltages is input to a gate, and a control circuit that generates a first control signal controlling a gate voltage of a transistor included in the output circuit, a second control signal controlling a voltage in a back-gate region of the transistor, and a third control signal controlling a voltage in a deep well region. The control circuit sets a voltage difference between the first and second control signals to be equal to or smaller than the larger one of a voltage difference between the first and third voltages and a voltage difference between the second and third voltages.