A semiconductor device includes an input determination circuit. The input determination circuit includes: a comparator that is driven based on a first reference potential and includes an input voltage terminal and a reference voltage terminal; a reference voltage generation circuit that inputs a reference voltage that is generated from a connection point between a constant current source and a resistor to the reference voltage terminal of the comparator, the constant current source and the resistor being interposed between a second reference potential that is separated from the first reference potential and a third potential that is higher than the first reference potential and the second reference potential; and a first low pass filter that is interposed between a signal input system that is connected to the input voltage terminal of the comparator and the second reference potential.