Patent ID: 9240717
Filing Date: 2016-01-19
CPC Classification: H02M

Claim Text:
1. A switching power supply device comprising: a switching controller of a non-linear control type, for generating an output voltage from an input voltage by performing on/off control of a switching element according to a result of comparison of a feedback voltage with a reference voltage; and an on-period setter for monitoring a switch voltage appearing at an end of the switching element so as to set, based on a duty of the switch voltage, an on-period of the switching element in the switching controller, wherein the on-period setter increases the on-period of the switching element the higher the duty of the switch voltage is, and decreases the on-period of the switching element the lower the duty of the switch voltage is, wherein the on-period setter includes: wherein the first voltage generation circuit includes: wherein the second voltage generation circuit includes: wherein the constant-current source and the level shifter operate by being fed with a same internal supply voltage.