Patent ID: 8952668
Filing Date: 2015-02-10
Classification: H02M

Abstract:
1. A switching power supply device operable to use a nonlinear control manner that switches on/off a switch element to generate an output voltage from an input voltage, the switching power supply device comprising: a reference voltage generation portion for generating a reference voltage; a ripple injection portion operable to use a switch voltage at one end of the switch element to generate a ripple component, and to inject the ripple component into the reference voltage to generate a ripple reference voltage; a comparator operable to compare a feedback voltage corresponding to the output voltage with the ripple reference voltage; a switching control portion operable to perform on/off control on the switch element based on an output signal of the comparator; and an offset adjustment portion operable to generate an offset voltage corresponding to the switch voltage, and setting any of the reference voltage, the feedback voltage, and the ripple reference voltage to the offset voltage, wherein the ripple injection portion comprises a first amplifier having a non-inverting input end connected to an application end of the reference voltage, an inverting input end connected to an application end of the switch voltage through a first resistor, and an output end connected to an application end of the ripple reference voltage and also connected to the inverting input end through a second resistor and a first capacitor, respectively.