Analysis and Design of the Dual Edge Controller for the Fast Transient Voltage Regulator

Achieving faster dynamic response is one of the big challenges for the future microprocessor voltage regulators (VR). It is well known that the system bandwidth needs to be higher to get a faster dynamic response but the system bandwidth is usually limited by the phase shift near the switching frequency. In this paper, the existing theories for this phase shift and efforts to achieve a faster transient response are summarized. A higher bandwidth design using a dual edge controller is analyzed. The bandwidth is designed to be larger than one half of the switching frequency. The design is then verified with the hardware.