High efficiency DC-DC buck converter with 60/120-MHz switching frequency and 1-A output current

Abstract

This DC-DC buck converter is able to operate up to 120-MHz switching frequency with peak power efficiency of 87% for 75% duty cycle and 93% at 60 MHz. Key feature of this design is a new control method that replaces the conventional op-amp based scheme. The proposed circuit uses a current-mode control and a voltage-to-pulse converter for the PWM. The circuit, fabricated using a 0.18-µm CMOS technology, reaches a peak load regulation of 20 mV/V and line regulation of 0.5 mV/V at 300 mA. The used 36-nH inductance and 4.7-µF capacitor are suitable for SiP realizations.