A signal generation circuit includes: a capacitor charged and discharged by a current proportional to an input voltage; a switch controlling charging and discharging of the capacitor based on an output signal of a comparator that compares a feedback voltage according to an output voltage and a predetermined first reference voltage; a reference voltage generation unit generating a second reference voltage that is generated by adding an offset voltage proportional to the input voltage to an output proportional voltage proportional to the output voltage; and a comparator comparing a terminal voltage of the capacitor and the second reference voltage, and generates an ON-time signal based on an output signal of the comparator.