CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2017-186575, filed on Sep. 27, 2017, the entire contents of which are incorporated herein by reference.

FIELD

The embodiments discussed herein are related to a power-supply apparatus and a power-supply method.

BACKGROUND

A power-supply apparatus has been known that has a duty-ratio determiner that determines a duty ratio of a control signal for a switching element in a power supply circuit so that an output voltage of the power supply circuit gets close to a target voltage (see Japanese Laid-open Patent Publication No. 2017-085820). A permissible-range calculator calculates a permissible range of the duty ratio, based on a current output from the power supply circuit and detected by a current detection circuit. When the duty ratio determined by the duty-ratio determiner is within the permissible range, an output portion outputs the duty ratio determined by the duty-ratio determiner, and when the duty ratio determined by the duty-ratio determiner is outside the permissible range, the output portion causes the power supply circuit to stop. Thus, in the power-supply apparatus, even when the current detection circuit fails, the power supply circuit can be stopped when overcurrent flows to the power supply circuit.

SUMMARY

According to an aspect of the invention, a power-supply apparatus includes a power supply circuit to which an input voltage and an input current are input, configured to include a switching element to be controlled by a control signal so as to generate an output voltage and an output current, a memory, and a processor coupled to the memory and the processor configured to calculate a first duty ratio of the control signal so that the output voltage approaches a target voltage, calculate a second duty ratio of the control signal for the switching element, based on the input voltage, the input current, the output voltage, and the output current, detect deterioration of the power supply circuit, based on the first duty ratio and the second duty ratio, generate the control signal of the first duty ratio when the power supply circuit has not deteriorated, and generate the control signal for stopping the power supply circuit when the power supply circuit has deteriorated.

The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.

