A Monolithic High-Performance Buck Converter With Enhanced Current-Mode Control and Advanced Protection Circuits
A monolithic high-performance step-down dc-dc converter for high power point-of-load application is presented in this paper. A novel adaptive quadratic slope compensation method and an adaptive antijittering ramp scheme are proposed to enhance the performance of widely used peak current-mode control. A fast overcurrent detection method together with a robust driver control logic design has been introduced to increase the circuits' reliability. The dc-dc converter has been designed and fabricated in a 0.35-μm Bipolar-CMOS-DMOS process with an area of 6 mm2. With the proposed enhanced current-mode control, our design allows more flexibility on inductor selection, switching frequency, and output voltage. Experimental results have shown great adaptability for various application configurations. This converter has also shown fast line step response and low PWM jittering. It can operate at beyond 9-A peak current and up to 1.4-MHz switching frequency with supply voltage from 2.35 to 6 V. Measured peak efficiency is 96.6% and over 92% efficiency for 6-A output current is realized as well.