Patent ID: 8581564
Filing Date: 2013-11-12
Classification: H02M

Abstract:
1. A switching power supply apparatus, comprising: an output transistor configured to generate an output voltage from an input voltage based on an ON/OFF control of the output transistor; a reference voltage generating unit configured to generate a reference voltage; a ripple injection unit configured to inject a ripple component into the reference voltage to generate a ripple reference voltage; a comparator configured to compare a feedback voltage based on the output voltage with the ripple reference voltage to generate a comparison signal; and a switching controller configured to perform the ON/OFF control of the output transistor based on the comparison signal, wherein the ripple injection unit includes: a charging/discharging portion configured to generate a charge/discharge current based on the ON/OFF control of the output transistor; a capacitor which is charged/discharged by the charge/discharge current; and a gm amplifier configured to bias one end of the capacitor by using the reference voltage, and wherein the ripple reference voltage is output from the one end of the capacitor.