Simple Low-Cost Hysteretic Controller for Single-Phase Synchronous Buck Converters

This paper presents a simple low-cost control architecture for low-voltage hysteretic regulators supplying loads with low-to-medium current consumption. Only two sensed voltages, a passive filter network and a hysteretic comparator are required to implement the main control functions: the output voltage regulation and the adaptive voltage positioning. This paper also shows that other previously reported low-cost control solutions have an important design tradeoff between load transient response and efficiency. In the proposed controller, the closed-loop output impedance can be designed to be resistive and the switching frequency can be adjusted to be independent of the output impedance requirement so that the load transient response and the efficiency can be optimized separately. Experimental results validate the performance of the proposed controller (i.e., a load transient response with insignificant output voltage overshoot and selectable switching frequency independent of the output impedance requirement).

[1]  T. Nabeshima,et al.  Analysis and design considerations of a buck converter with a hysteretic PWM controller , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[2]  S. A. Chickamenahalli,et al.  Effect of target impedance and control loop design on VRM stability , 2002, APEC. Seventeenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.02CH37335).

[3]  J. Abu-Qahouq,et al.  Multiphase voltage-mode hysteretic controlled DC-DC converter with novel current sharing , 2004, IEEE Transactions on Power Electronics.

[4]  A. Waizman,et al.  Resonant free power network design using extended adaptive voltage positioning (EAVP) methodology , 2001 .

[5]  Han Ho Choi.  Sliding-Mode Output Feedback Control Design , 2008, IEEE Transactions on Industrial Electronics.

[6]  Rais Miftakhutdinov,et al.  An Analytical Comparison of Alternative Control Techniques for Powering Next-Generation Microprocessors , 2001 .

[7]  Y.M. Lai,et al.  On the practical design of a sliding mode voltage controlled buck converter , 2005, IEEE Transactions on Power Electronics.

[8]  S. Narendra,et al.  A 480-MHz, multi-phase interleaved buck DC-DC converter with hysteretic control , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[9]  Caisheng Wang,et al.  Analysis of Inductor Current Sharing in Nonisolated and Isolated Multiphase dc–dc Converters , 2007, IEEE Transactions on Industrial Electronics.

[10]  M. Castilla,et al.  Interleaving of parallel DC-DC converters using sliding mode control , 1998, IECON '98. Proceedings of the 24th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.98CH36200).

[11]  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).

[12]  F.C. Lee,et al.  Optimal design of the active droop control method for the transient response , 2003, Eighteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2003. APEC '03..

[13]  A.Q. Huang,et al.  A novel VRM control with direct load current feedback , 2004, Nineteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2004. APEC '04..

[14]  F.C. Lee,et al.  Adaptive voltage position design for voltage regulators , 2004, Nineteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2004. APEC '04..

[15]  Josep M. Guerrero,et al.  Comparative study of hysteretic controllers for single-phase voltage regulators , 2008 .

[16]  J. Miret,et al.  Control techniques for the single magnetic push-pull forward converter with built-in input filter , 2005, Proceedings of the IEEE International Symposium on Industrial Electronics, 2005. ISIE 2005..

[17]  Josep M. Guerrero,et al.  Design of voltage-mode hysteretic controllers for synchronous buck converters supplying microprocessor loads , 2005 .

[18]  Josep M. Guerrero,et al.  Designing VRM Hysteretic Controllers for Optimal Transient Response , 2007, IEEE Transactions on Industrial Electronics.

[19]  K. Nishijima,et al.  Multi-Phase Converter Controlled by Hysteretic PWM Method , 2007, 2007 Power Conversion Conference - Nagoya.

[20]  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).

[21]  Issa Batarseh,et al.  Interleaved synchronous buck regulator with hysteretic voltage control , 2001, 2001 IEEE 32nd Annual Power Electronics Specialists Conference (IEEE Cat. No.01CH37230).

[22]  Dan Chen,et al.  Modeling and Design for a Novel Adaptive Voltage Positioning (AVP) Scheme for Multiphase VRMs , 2008, IEEE Transactions on Power Electronics.

[23]  Fred C. Lee,et al.  Design considerations for VRM transient response based on the output impedance , 2003 .

[24]  Khai D. T. Ngo,et al.  Dynamic Characterization of the Synthetic Ripple Modulator in a Tightly Regulated Distributed Power Application , 2009, IEEE Transactions on Industrial Electronics.

[25]  Juan Suardíaz Muro,et al.  Effect of the Output Impedance in Multiphase Active Clamp Buck Converters , 2008, IEEE Transactions on Industrial Electronics.

[26]  Jiin-Chuan Wu,et al.  A ripple control buck regulator with fixed output frequency , 2003 .

[27]  Jian Sun,et al.  Characterization and performance comparison of ripple-based control methods for voltage regulator modules , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[28]  Khai D. T. Ngo,et al.  Pulsewidth modulator with carriers derived from converter waveforms , 2005 .

[29]  C.K. Tse,et al.  Adaptive feedforward and feedback control schemes for sliding mode controlled power converters , 2006, IEEE Transactions on Power Electronics.

[30]  R. Redl,et al.  Optimizing the load transient response of the buck converter , 1998, APEC '98 Thirteenth Annual Applied Power Electronics Conference and Exposition.