A duty timing detector includes a saw-tooth voltage generator that outputs a saw-tooth voltage in synchronization with a toggle signal repeatedly transitioning between a high level and a low level. A sample block obtains a level of the saw-tooth voltage in synchronization with the toggle signal and outputs the obtained level as a first sample voltage. A hold block stores the first sample voltage in synchronization with the toggle signal and outputs the stored first sample voltage as a second sample voltage. A voltage divider divides the second sample voltage to output a division voltage. A comparator compares the saw-tooth voltage and the division voltage to detect a target timing in each duty of the toggle signal.