A 3MHz Low-Voltage Buck Converter with Improved Light Load Efficiency

Abstract

A low-voltage synchronous buck converter has been designed and fabricated in a 0.5mum CMOS technology. The converter uses two charge conservation techniques to increase efficiency at light loads while still operating in PWM mode at a switching frequency of 3MHz. These techniques reduce IC power loss from 11.5mW to 8.9mW, a 22.7% reduction, for l <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">load</sub> = 20mA and V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">out</sub> = 1.8V.