The semiconductor integrated circuit includes an inverting amplifier that generates an oscillation signal with an input connected to the first terminal and an output connected to the second terminal, the inverting amplifier fluctuating in gain in response to a gain control signal. The semiconductor integrated circuit includes a waveform shaping circuit that shapes a waveform of the oscillation signal and outputs a clock signal to a clock signal output terminal. The semiconductor integrated circuit includes an edge detecting circuit that detects an edge of the clock signal and outputs the gain control signal at a time of the edge.