US 12,244,216 B2
Circuits and method for reducing light load power dissipation of a voltage converter
Pengfei Liu, Hangzhou (CN)
Assigned to Chengdu Monolithic Power Systems Co., Ltd., Sichuan (CN)
Filed by Chengdu Monolithic Power Systems Co., Ltd., Chengdu (CN)
Filed on Aug. 11, 2022, as Appl. No. 17/886,110.
Claims priority of application No. 202110950053.X (CN), filed on Aug. 18, 2021.
Prior Publication US 2023/0058021 A1, Feb. 23, 2023
Int. Cl. H02M 1/00 (2007.01)
CPC H02M 1/0032 (2021.05) [H02M 1/0025 (2021.05)] 20 Claims
OG exemplary drawing
 
1. A control circuit for a voltage converter, comprising:
a feedback compensation signal generating circuit configured to receive a feedback voltage and provide a feedback compensation signal based on the feedback voltage and a reference voltage;
a hysteresis comparison circuit configured to receive an output representation signal, a first threshold, and a second threshold, and to provide a selection signal based on a comparison of the output representation signal with the first threshold and the second threshold;
a selection circuit configured to receive the feedback compensation signal, an ultra-light load feedback value and the selection signal, and to select one of the feedback compensation signal and the ultra-light load feedback value as a selected feedback compensation signal based on the selection signal, wherein when the selection signal indicates the output representation signal is less than the first threshold, the ultra-light load feedback value is selected as the selected feedback compensation signal, when the selection signal indicates the output representation signal is greater than the second threshold, the feedback compensation signal is selected as the selected feedback compensation signal; and
a switch control circuit configured to receive the selected feedback compensation signal and to provide a switch control signal based on the selected feedback compensation signal;
wherein the second threshold is greater than the first threshold, and wherein, at the time the output representation signal is equal to the second threshold, the ultra-light load feedback value is greater than a value of the feedback compensation signal.