Digital Multiphase Constant-On-Time Regulator based on Voltage Controlled Oscillator

摘要

During the last decade, the technology's evolution of modern microprocessors required better computing performance and more efficient power management platforms. Faster processor in a less power envelope has led to lower supply voltages down to 1.2V according to the thinner gate oxides used and higher currents even up to 200A. Power systems are becoming increasingly complex; the classical concept of control has gradually evolved into the more general problem of power management, demanding functionalities that are hardly achievable in analog controllers. The high flexibility offered by digital controllers and their capability to implement sophisticated control strategies, together with the programmability of controller parameters, make digital control very attractive for improving the features of dc-dc converters. By using of PC-Based design tools, the digital controller can be fully configured and the power supply parameters can be monitored as well in order to optimize the total system efficiency. In this paper an innovative digital control technique is proposed for multiphase buck topologies but it could be applied to only one phase system also. This new digital modulator is derived from analog STVCOT™ and combines advantages of both voltage mode and constant on-time techniques.