Patent ID: 8076917

Claim:
A buck switching regulator with improved mode transition comprising: (1) a first circuit including: an output power stage for converting an input voltage to an output voltage; a comparison and amplification circuit comparing a feedback signal relating to the output voltage with a reference signal to generate a first voltage signal; a first comparator comparing the first voltage signal with a ramp signal to generate a first pulse-width modulation (PWM) signal; wherein the first PWM signal controls the output power stage during a fixed-frequency PWM mode (FPWM mode), and the first voltage signal controls the output power stage during a pulse skipping mode (PSK mode); and (2) a second circuit generating a second voltage signal during the PSK mode, the second voltage signal being substantially close to the first voltage signal during the FPWM mode, and providing the second voltage signal as a starting point of the first voltage signal during the PWM mode.