In this study，we propose a novel fast-transient-response，low-latency ZCD comparator to reduce the complexity of the DCM control circuit of the Boost converter with high output and a high-side P-type power transistor. Furthermore，the Boost converter is enabled with a lower maximum reverse inductor current at light load. In this ZCD comparator，we include a transient response enhancement circuit to increase the generation speed of the output up-jump of the comparator. We employ the cadence virtuoso tool under the SMIC 0. 18-μm BCD process to simulate and verify the function and performance of the proposed ZCD comparator. The simulation results demonstrate that the proposed ZCD comparator exhibits an up-jump delay as low as 4 ns and quiescent current consumption of only 10 μA. It can directly control the boost converter to work under DCM on the high side. Within the load current range of 1 to 200 mA，the boost converter exhibits a reverse inductor current maximum that is at least 28% lower than that using a conventional ZCD comparator，along with a maximum conversion efficiency improvement of 13. 2%.