A high-performance PWM controller with adjustable current limit

A high-performance pulse width modulation (PWM) controller with adjustable current limit technique, which is suitable for peak-current-mode (PCM) DC-DC converters, especially in high-power application, is proposed in this paper to guarantee converters work properly. In order to realize high-performance analog circuit with smaller size in high-power application, a novel control method with concept of relative ground is introduced in the proposed PWM controller. Besides, compared with conventional PCM DC-DC converters, the change of peak current limit with the change of duty cycle is greatly decreased through a special strategy. The proposed high-performance PWM controller has been validated with 0.6-μm CD process based on a monolithic current-mode BUCK converter capable of driving up to 3A loads with supply voltage from 4.5 to 23V. Simulation results demonstrate that the proposed PWM controller can guarantee the BUCK converter operating properly.