Dynamic physical limits of buck converters: The T0/4 transient benchmark rule

This paper presents practical benchmarking transient rules for buck converters that result from establishing the physical dynamic limits of the system. The theoretical limit of performance during transients is found in the normalized form, providing valuable insight into the behavior of the topology and facilitating a benchmarking tool for power designers/researchers. For generality and simplicity, the results are presented in the normalized geometrical domain for start-up transient and sudden load changes. Experimental results of a 30W buck converter operating at the physical limit are presented, validating the resulting characterization of the optimal transient.