Modular graphing technique for small-signal low-frequency characterizations of PWM DC/DC regulators

This paper addresses the development of a modular graphing technique for small-signal low-frequency characterizations of pulse-width-modulation (PWM) DC/DC regulators. The methodology starts with the derivation of a unified input sensitivity graph for a single circuit topology to correlate the state-variable sensitivities with the topology duration and the input source. By integrating with previously developed state-variable sensitivity graphing technique, the overall regulator sensitivities in one switching cycle, and hence the small-signal transfer characteristics are obtained by cascading the respective graphs in accordance with the sequence of the topologies. The proposed method is exemplified by analyzing a PWM boost regulator