US 12,295,079 B2
LED driving circuit and LED lighting circuit
Jie Fu, Shanghai (CN); Shiguang Sun, Shanghai (CN); Zhiquan Chen, Shanghai (CN); Feng Ju, Shanghai (CN); Yu Wang, Shanghai (CN); and Gang Wang, Shanghai (CH)
Assigned to SIGNIFY HOLDING, B.V., Eindhoven (NL)
Appl. No. 18/556,193
Filed by SIGNIFY HOLDING B.V., Eindhoven (NL)
PCT Filed Apr. 19, 2022, PCT No. PCT/EP2022/060237
§ 371(c)(1), (2) Date Oct. 19, 2023,
PCT Pub. No. WO2022/228935, PCT Pub. Date Nov. 3, 2022.
Claims priority of application No. PCT/CN2021/089720 (WO), filed on Apr. 25, 2021; and application No. 21185224 (EP), filed on Jul. 13, 2021.
Prior Publication US 2024/0196497 A1, Jun. 13, 2024
Int. Cl. H05B 45/50 (2022.01); H05B 45/38 (2020.01)
CPC H05B 45/50 (2020.01) 10 Claims
OG exemplary drawing
 
1. A driving circuit for a light emitting source, comprising
an input adapted to receive a power supply;
a conversion circuit, adapted to convert the power supply and provide a converted power, comprising a power switch;
an output, adapted to output the converted power;
an output capacitor (62) connected at the output;
a first control circuit coupled to the output and connected to the power switch, adapted to sense a voltage corresponding to the voltage on the output capacitor and control the power switch operate in a power-reducing mode to reduce the converted power when the voltage corresponding to the voltage on the output capacitor sensed by the first control circuit exceeds a first level; and
a second control circuit connected to the output capacitor and connected to a control terminal of the power switch, adapted to:
sense a voltage at the output capacitor and
electrically connect the output capacitor and the control terminal, and apply, between the control terminal and a current-out terminal of the power switch, a first portion of the voltage on the output capacitor which first portion being higher than a maximum rating voltage for the control terminal and the current-out terminal, so as to damage and make the power switch unoperational permanently, when the voltage at the output capacitor sensed by the second control circuit exceeds a second level.