A Feasibility Study for Advanced PMBus DC/DC Integrated Circuits

This paper discusses advanced implementation of the feedback control law within an analog mode controller for a Point-of-Load converter with Power Management Bus (PMBus) access. This type of dc/dc converter is used for computer or telecom power. Due to high switching frequency and cost concerns related to microcontrollers, the conventional analog-mode controller is maintained by industry. This implies implementation of the control law with a R-C network on the feedback of an operational amplifier. For enhanced performance, this paper proposes to adjust the control gains with the operation point through a digital 12C potentiometer. A feasibility study is demonstrating the performance enhancements when an 12C potentiometer is added into the existing dc/dc PMBus integrated circuits.