US 11,751,306 B2
Buck topological circuit for power supply
Pingwei Zhang, Suzhou (CN); and Weiwei Yang, Suzhou (CN)
Assigned to Suzhou Opple Lighting Co., Ltd., Suzhou (CN); and Opple Lighting Co., Ltd., Shanghai (CN)
Filed by OPPLE LIGHTING CO., LTD., Shanghai (CN); and SUZHOU OPPLE LIGHTING CO., LTD., Suzhou (CN)
Filed on Dec. 28, 2021, as Appl. No. 17/564,176.
Application 17/564,176 is a continuation of application No. PCT/CN2020/111260, filed on Aug. 26, 2020.
Claims priority of application No. 201921513333.9 (CN), filed on Sep. 11, 2019.
Prior Publication US 2022/0124888 A1, Apr. 21, 2022
Int. Cl. H05B 45/345 (2020.01); H05B 45/375 (2020.01); H02M 7/06 (2006.01)
CPC H05B 45/345 (2020.01) [H02M 7/06 (2013.01); H05B 45/375 (2020.01)] 8 Claims
OG exemplary drawing
 
1. A BUCK topological circuit for power supply, comprising:
a rectification circuit, connected to input terminals, a first output terminal, and an earth wire and configured to convert an alternating-current signal at the input terminals to a direct-current signal and transmit the direct-current signal to the first output terminal;
a first filter energy-storage circuit, connected to the first output terminal and the earth wire and configured to filter a signal at the first output terminal and store electric energy;
a step-down constant-current driver chip, having an input terminal connected to the first output terminal so that a voltage at the input terminal is consistent with a bus voltage, a drain electrode connected to a first node and a current sampling terminal connected to a second node so that the step-down constant-current driver chip responses to the signal at the first output terminal to work, wherein the step-down constant-current driver chip does not require an external power supply capacitor;
an output current setting circuit, connected to the second node and the earth wire and configured to set an output current;
a freewheeling circuit, connected to the first output terminal and the first node;
a transformer, connected to the first node and a second output terminal and configured to convert a voltage between the first output terminal and the first node to an output voltage; and
a second filter energy-storage circuit, connected to the first output terminal and the second output terminal and configured to filter the signal at the first output terminal and store electric energy.