Design of voltage-mode hysteretic controllers for synchronous buck converters supplying microprocessor loads

The use of voltage-mode hysteretic control is a popular way to power modern microprocessor loads having high slew-rate current transients. A simple methodology is presented for the control design of synchronous buck hysteretic regulators based on sliding-mode control theory. The major advantage of this design approach is that the large-signal dynamic model of the hysteretic regulator can be expressed in close-loop operation as a linear system, thanks to which regular linear control techniques can be easily employed to check stability and to impose a satisfactory transient as well as steady-state performance. A detailed design example and experimental results are reported, confirming the validity of the proposed control design methodology.

[1]  R. Miftakhutdinov,et al.  Analysis and optimization of synchronous buck converter at high slew-rate load current transients , 2000, 2000 IEEE 31st Annual Power Electronics Specialists Conference. Conference Proceedings (Cat. No.00CH37018).

[2]  I. Batarseh,et al.  Multiphase voltage-mode hysteretic controlled VRM with DSP control and novel current sharing , 2002, APEC. Seventeenth Annual IEEE Applied Power Electronics Conference and Exposition (Cat. No.02CH37335).

[3]  Peng Xu,et al.  Design of 48 V Voltage regulator modules with a novel integrated magnetics , 2002 .

[4]  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).

[5]  Vadim I. Utkin,et al.  Sliding Modes in Control and Optimization , 1992, Communications and Control Engineering Series.

[6]  Seth R. Sanders,et al.  Active clamp circuits for switchmode regulators supplying microprocessor loads , 1997, PESC97. Record 28th Annual IEEE Power Electronics Specialists Conference. Formerly Power Conditioning Specialists Conference 1970-71. Power Processing and Electronic Specialists Conference 1972.

[7]  R. Decarlo,et al.  Variable structure control of nonlinear multivariable systems: a tutorial , 1988, Proc. IEEE.

[8]  Allen B. Rosenstein,et al.  Free Running-Switching Mode Power Regulator: Analysis and Design , 1964, IEEE Transactions on Aerospace.

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

[10]  Fred C. Lee,et al.  Single shot transient suppressor (SSTS) for high current high slew rate microprocessor , 1999, APEC '99. Fourteenth Annual Applied Power Electronics Conference and Exposition. 1999 Conference Proceedings (Cat. No.99CH36285).

[11]  John Y. Hung,et al.  Variable structure control: a survey , 1993, IEEE Trans. Ind. Electron..

[12]  Milan M. Jovanovic,et al.  Design considerations for low-voltage on-board DC/DC modules for next generations of data processing circuits , 1996 .

[13]  A. Isidori.  Nonlinear Control Systems , 1985 .