A novel input filter compensation scheme for switching regulators

The interaction between the input filter and the control loop of switching regulators often results in detrimental effects, such as loop instability, degradation of transient response and audiosusceptibility, etc. The concept of pole-zero cancellation is employed to mitigate some of these detrimental effects and is implemented using a novel feedforward loop, in addition to existing feeback loops of a buck regulator. Experimental results are presented which show excellent correlation with theory.