Patent attributes
A circuit device includes a clock generation circuit, a signal generation circuit, a phase comparison circuit, and a processing circuit. The signal generation circuit generates a first signal making the transition at a transition timing of a first clock signal, a fine-judging signal making the transition at a transition timing of a second clock signal, a first coarse-judging signal making the transition at a transition timing of the second clock signal anterior to the fine-judging signal, and a second coarse-judging signal making the transition at a transition timing of the second clock signal posterior to the fine-judging signal. The phase comparison circuit performs the phase comparison between the second signal making the transition based on the first signal and each of the fine-judging signal, the first coarse-judging signal, and the second coarse-judging signal. The processing circuit sets the transition timing of the first signal and the transition timing of the fine-judging signal based on the phase comparison result, and converts a time difference between the first signal and the second signal into a digital value based on the setting result.