Critical inductance in voltage regulator modules

Multichannel interleaving makes it possible to use small inductances to improve voltage regulator modules' (VRMs) transient responses. However, smaller inductances reduce efficiency. Analysis shows that the transient responses are not only determined by the inductances but also the control bandwidths. This paper presents the concept of critical inductance in VRM. Critical inductance is the largest inductance that gives the fastest transient responses. Critical inductance is a good reference for optimal VRM design. Critical inductance is a function of the feedback control, the step current magnitude and the steady-state operating point.

[1]  Peng Xu,et al.  Investigation of candidate VRM topologies for future microprocessors , 2000 .

[2]  Vatche Vorperian,et al.  Generation, Classification and Analysis of Switched-Mode DC-to-DC Converters by the Use of Converter Cells , 1986, INTELEC '86 - International Telecommunications Energy Conference.

[3]  Milan M. Jovanovic,et al.  Design considerations for low-voltage on-board DC/DC modules for next generations of data processing circuits , 1995, Proceedings of 1995 International Conference on Power Electronics and Drive Systems. PEDS 95.

[4]  Pit-Leong Wong,et al.  Performance Improvements of Multi-Channel Interleaving Voltage Regulator Modules with Integrated Coupling Inductors , 2001 .

[5]  Milan M. Jovanovic,et al.  Design considerations for 12-V/1.5-V, 50-A voltage regulator modules , 2000, APEC 2000. Fifteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.00CH37058).

[6]  F. C. Lee,et al.  Voltage regulator module (VRM) transient modeling and analysis , 1999, Conference Record of the 1999 IEEE Industry Applications Conference. Thirty-Forth IAS Annual Meeting (Cat. No.99CH36370).