New NTC MLCC Capacitor for Improved Transient Performance in Multiphase Voltage Regulators

This paper addresses the current methodologies for lossless DCR sensing circuits typically used in high current switching mode voltage regulators for both single phase and multiple phase topologies. It introduces a new negative TC (NTC) capacitor which exhibits near linear capacitance loss with an increase of temperature and compensates for the positive change of the output inductor´s DCR. The improvement to the matching of the L/DCR and Rsense x Csense time constants is explained and is compared to existing lossless DCR sensing circuits using NTC thermistors. And finally, actual improved testing results are shown and discussed.