US 12,249,919 B2
Control circuit, system and method for switched-mode power supply
Yanmei Guo, Shanghai (CN); Yihui Chen, Shanghai (CN); Haifeng Miao, Shanghai (CN); Yuehui Li, Shanghai (CN); Xiaoru Gao, Shanghai (CN); and Zhen Zhu, Shanghai (CN)
Assigned to SHANGHAI BRIGHT POWER SEMICONDUCTOR CO., LTD., Shanghai (CN)
Filed by SHANGHAI BRIGHT POWER SEMICONDUCTOR CO., LTD., Shanghai (CN)
Filed on Aug. 31, 2023, as Appl. No. 18/240,861.
Application 18/240,861 is a continuation in part of application No. 17/555,096, filed on Dec. 17, 2021, granted, now 11,799,379.
Claims priority of application No. 202011625428.7 (CN), filed on Dec. 31, 2020.
Prior Publication US 2023/0412082 A1, Dec. 21, 2023
Int. Cl. H02M 3/335 (2006.01); H02M 1/00 (2006.01); H02M 1/08 (2006.01); H02M 1/32 (2007.01); H02M 1/44 (2007.01)
CPC H02M 3/33507 (2013.01) [H02M 1/0032 (2021.05); H02M 1/0054 (2021.05); H02M 1/08 (2013.01); H02M 1/32 (2013.01); H02M 1/44 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A control circuit for a switched-mode power supply for driving a first switch in the switched-mode power supply to convert an input voltage into an output voltage, the control circuit comprising
an on-time control unit, which receives a first signal and a second signal, the first signal characterizing a current limiting value and the second signal characterizing a current flowing through the first switch to select an operating mode of the switched-mode power supply based on the first signal and the second signal,
wherein the on-time control unit compares the current flowing through the first switch with a first reference current value generated based on the current limiting value and the switched-mode power supply is configured to be in a first operating mode when a peak value of the current flowing through the first switch does not surpass the first reference current value, and
wherein the on-time control unit determines a turn-off instant for the first switch based on the instant of that the current flowing through the first switch increases to the first reference current value in the first operating mode, so that the peak current flowing through the first switch is able to reach the first reference current value.