US 12,413,154 B2
Control circuit for synchronous rectification switch of power converter
Che-Hao Meng, Hsinchu (TW); Chien Lung Li, Hsinchu County (TW); and Chia-Hsien Liu, Hsinchu County (TW)
Assigned to Power Forest Technology Corporation, Hsinchu County (TW)
Filed by Power Forest Technology Corporation, Hsinchu County (TW)
Filed on Nov. 14, 2023, as Appl. No. 18/509,208.
Claims priority of application No. 112137134 (TW), filed on Sep. 27, 2023.
Prior Publication US 2025/0105754 A1, Mar. 27, 2025
Int. Cl. H02M 3/335 (2006.01); H02M 1/00 (2006.01)
CPC H02M 3/33592 (2013.01) [H02M 1/0012 (2021.05)] 10 Claims
OG exemplary drawing
 
1. A control circuit for a synchronous rectification switch of a power converter, wherein the synchronous rectification switch and a transformer of the power converter are coupled to a connection node, the control circuit comprising:
a first logic circuit, coupled to the connection node, and configured to receive a detection voltage on the connection node, and provide a detection signal according to the detection voltage;
an integrating circuit, coupled to the first logic circuit, and configured to perform an accumulation operation on an integrated voltage value based on the detection signal, and discharge the integrated voltage value when the integrated voltage value rises to a predetermined value, so as to generate a setting pulse;
a setting comparator, configured to receive the detection voltage and a first predetermined voltage, and provide a comparison signal according to a comparison result of the detection voltage and the first predetermined voltage;
a logic gate, coupled to the integrating circuit and the setting comparator, and configured to output a setting signal according to the setting pulse and the comparison signal; and
a second logic circuit, coupled to the logic gate, and configured to continuously provide a turn-on control signal in response to the setting signal,
wherein the synchronous rectification switch is turned on in response to the turn-on control signal.