An Improved Hysteresis Voltage Mode of Synchronous Rectifier Buck Circuit

To achieve high power and high efficiency over a wide load range, an improved hybrid hysteresis voltage mode for Buck circuit is proposed in this paper. The strategy and workflow of the proposed improved hybrid hysteresis voltage mode are demonstrated step by step. The output voltage performance of the Buck circuit with proposed hysteresis voltage mode is compared with the same circuit with typical hysteresis voltage mode. Numerical simulation results show that with the introduction of the PD link, the overshoot can be completely controlled or eliminated; with the introduction of the dynamic voltage reference, the static difference can be completely negligible; relatively stable input voltage improves its steady-state working frequency and the electromagnetic interference significantly. Thus, the proposed control strategy can not only achieve satisfied performance, but also provide a basis for further design and optimization.