Patent ID: 8278884

Claim:
A direct current-to-direct current (DC-DC) converter comprising: an inductor; a power supply configured to supply direct current (DC) to the inductor; a switching device configured to: control the supply of DC from the power supply to the inductor by switching between a conductive state and a disconnected state according to a modulation signal input to the switching device, and generate an electromotive force in response to the modulation signal; a signal output device configured to: generate the modulation signal, and increase or decrease a duty ratio of the modulation signal to increase or decrease the period of the conductive state of the switching device; a rectifier configured to rectify the generated electromotive force; a smoothing and charging device configured to smooth and charge the rectified electromotive force, wherein the smoothed and charged rectified electromotive force is supplied as an output voltage to a load connected in parallel with the smoothing and charging device; a voltage detector configured to detect an amount of decrease of the output voltage relative to a target voltage; an instruction device configured to instruct a monotonic increase of the duty ratio when the amount of decrease of the detected output voltage increases; and a delay device configured to: control the monotonic increase of the duty ratio according to the instruction from the instruction device, and allow the instruction device to provide the instruction to monotonically increase the duty ratio when the duty ratio is less than a value of 1.