US 12,470,139 B2
Control circuit with peak current limit for switching converters and control method thereof
Wangmiao Hu, Hangzhou (CN); Lijie Jiang, Hangzhou (CN); Chiahsin Chang, Sammamish, WA (US); and Jinghai Zhou, Bellevue, WA (US)
Assigned to Chengdu Monolithic Power Systems Co., Ltd., Sichuan (CN)
Filed by Chengdu Monolithic Power Systems Co., Ltd., Chengdu (CN)
Filed on May 30, 2023, as Appl. No. 18/325,365.
Claims priority of application No. 202210638756.3 (CN), filed on Jun. 7, 2022.
Prior Publication US 2023/0318452 A1, Oct. 5, 2023
Int. Cl. H02M 3/156 (2006.01); H02M 1/00 (2006.01)
CPC H02M 3/156 (2013.01) [H02M 1/0009 (2021.05)] 19 Claims
OG exemplary drawing
 
1. A control circuit for a switching converter, wherein the switching converter comprises a switching circuit, the switching circuit is turned ON and OFF by a switching control signal, and is further configured to convert an input voltage to an output voltage, the control circuit comprising:
a comparison circuit, configured to provide a voltage comparison signal by comparing a feedback signal with a voltage reference, wherein the feedback signal is representative of the output voltage;
a valley current limiting circuit, configured to provide a valley current comparison signal by comparing a current sense signal with a first current threshold, wherein the current sense signal is representative of a current flowing through the switching circuit;
a peak current limiting circuit, configured to provide an operational signal based on the valley current comparison signal and the switching control signal, and to provide a peak current comparison signal by comparing the operational signal with a second current threshold;
an ON time control circuit, configured to provide an ON time control signal based on the switching control signal; and
a switching control circuit, configured to provide the switching control signal based on the voltage comparison signal, the valley current comparison signal, the peak current comparison signal, and the ON time control signal to turn ON and OFF the switching circuit.