According to one embodiment, there is provided an open-drain-type output circuit which outputs a signal of an internal circuit. The output circuit includes a first signal output terminal, a first signal line, a first floating line, a first rectifier element, and a first ESD protection circuit. The first signal line connects the first signal output terminal and the internal circuit. Potential of the first floating line is not fixed. The first rectifier element is connected between the first signal output terminal and the first floating line. The first ESD protection circuit is connected between the first floating line and ground potential.