Semiconductor device and method

A method of controlling a semiconductor device, the semiconductor device including an oscillation circuit, a phase comparator circuit, a charge pump circuit, and a filter circuit, the oscillation circuit oscillating a clock signal with a frequency corresponding to a potential of a control signal, the charge pump circuit supplying a current corresponding to a signal from the phase comparator circuit, the filter circuit converting a current from the charge pump circuit into the control signal, the method comprising:

• setting a potential of the control signal to a calibration potential;
• executing calibration of a first frequency when the potential of the control signal is set to the calibration potential, the first frequency being a frequency of a first clock signal, the first clock signal being the clock signal oscillated by the oscillation circuit;
• after completion of the executing calibration,
• adjusting an initial phase error based on a phase of a reference clock signal, and
• generating a second clock signal being a clock signal obtained by performing frequency-division of the first clock signal to include the adjusted initial phase error;
• and
• causing the phase comparator circuit to compare phases between the reference clock signal and the second clock signal and output, as the signal from the phase comparator circuit, a result of the comparison of the phases.