SEMICONDUCTOR DEVICE

According to one embodiment, a semiconductor device includes the following configuration. A detection circuit detects a state of a clock signal. An amplification circuit changes a gain based on the state of the clock signal detected by the detection circuit. An amplification circuit amplifies a first voltage with the gain and outputs a second voltage obtained as a result of amplification. A conversion circuit converts the second voltage output from the amplification circuit to first data. An isolation circuit includes a driver and a receiver electrically isolated from the driver. The driver transmits a signal corresponding to the first data to the receiver. The receiver outputs second data corresponding to the signal transmitted from the driver. The output circuit outputs the second data output from the isolation circuit.