Investigation of candidate topologies for 12 V VRM

With higher input voltages and lower output voltages, the most popular voltage regulator module (VRM) topology-the multiphase buck converter-operates at very small duty cycles. The influence of duty cycle on the performance of a multiphase buck converter is investigated and the results show that both the transient response and the efficiency suffer from the very small duty cycle. Alternative topologies with extended duty cycles are explored in order to improve the efficiency without comprising the transient response. The topologies under investigation are multiphase tapped-inductor buck converter, multiphase coupled-buck converter and improved multiphase coupled-buck converter with built-in filters.

[1]  R. Miftakhutdinov.  Optimal design of interleaved synchronous buck converter at high slew-rate load current transients , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

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

[3]  J. Sebastián,et al.  Static and dynamic modeling of tapped-inductor dc-to-dc converters , 1987, IEEE Power Electronics Specialists Conference.

[4]  R. D. Middlebrook,et al.  Transformerless DC-to-DC Converters with Large Conversion Ratios , 1984, INTELEC '84 - International Telecommunications Energy Conference.

[5]  Koosuke Harada,et al.  The Cascade Connection of Switching Regulators , 1976, IEEE Transactions on Industry Applications.

[6]  K.D.T. Ngo,et al.  Steady-state analysis of the symmetrical push-pull power converter employing a matrix transformer , 1990, 21st Annual IEEE Conference on Power Electronics Specialists.

[7]  Milan M. Jovanovic,et al.  Design considerations for 12-V/1.5-V, 50-A voltage regulator modules , 2001 .

[8]  Dragan Maksimovic,et al.  Switching converters with wide DC conversion range , 1991 .

[9]  Ching-Shan Leu,et al.  A built-in-input filter forward converter , 1994, Proceedings of 1994 Power Electronics Specialist Conference - PESC'94.

[10]  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).

[11]  R. Middlebrook.  Transformerless DC-to-DC converters with large conversion ratios , 1988 .

[12]  Peng Xu,et al.  The active-clamp couple-buck converter-a novel high efficiency voltage regulator modules , 2001, APEC 2001. Sixteenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.01CH37181).

[13]  F. C. Lee,et al.  A high power density, high efficiency and fast transient voltage regulator module with a novel current sensing and current sharing technique , 1999, APEC '99. Fourteenth Annual Applied Power Electronics Conference and Exposition. 1999 Conference Proceedings (Cat. No.99CH36285).