| 主权项 |
1. A semiconductor integrated circuit that controls oscillation of a crystal resonator, the semiconductor integrated circuit being applied to an oscillation system comprising a first load capacitance with a first end connected to ground and a second end connected to a first terminal, a second load capacitance with a first end connected to the ground and a second end connected to a second terminal, and a crystal resonator with a first end connected to the second end of the first load capacitance and a second end connected to the second end of the second load capacitance,
the semiconductor integrated circuit comprising: 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; a waveform shaping circuit that shapes a waveform of the oscillation signal and outputs a clock signal to a clock signal output terminal; and an edge detecting circuit that detects an edge of the clock signal and outputs the gain control signal at a time of the edge, wherein the edge detecting circuit outputs the gain control signal that sets the gain of the inverting amplifier at a first value if capacitance values of the first load capacitance and the second load capacitance are not lower than a predetermined threshold, and the edge detecting circuit outputs the gain control signal that sets the gain of the inverting amplifier at a second value lower than the first value if the capacitance values are lower than the predetermined threshold. |
