High-efficiency low-noise pulse-width modulation DC–DC buck converter based on multi-partition switching for mobile system- on-a-chip applications

This study presents a high-efficiency low-noise pulse-width modulation (PWM) DC–DC buck converter based on multi-partition switching for mobile system-on-a-chip applications. A multi-partition switching technique is employed for the control of large current driving switches to minimise the switching noise. In addition, a PWM control with a switching frequency of 2 MHz is applied for the driving of output stage with a heavy load to optimise the power efficiency. The prototype DC–DC buck converter with an active die area of 0.28 mm was implemented using a 0.18 μm bipolar-CMOS–DMOS (BCD) process. The peak power efficiency is 93%, while supplying an output current of 200 mA and an output voltage of 1.8 V.