A Novel Adaptive Quasi-Constant On-Time Current-Mode Buck Converter

There have been a variety of constant on-time (COT) controllers for dc power converter applications reported in recent years
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. In this paper, a novel adaptive quasi-constant on-time current-mode control scheme is proposed and implemented in buck converters. While preserving the advantages of the conventional COT current-mode converters, this scheme allows fast transient response to step-load that is a critical requirement of a computer load with smart management. A small-signal model of the proposed circuit is also developed. Experimental results are also provided. This scheme is well suited for the next-generation dc converters for power management central-processor-unit devices.