US 12,004,276 B2
Driving circuit, and LED circuit and a driving method
Liang Shi, Shanghai (CN); and Shan Wang, Shanghai (CN)
Assigned to SIGNIFY HOLDING B.V.
Appl. No. 17/922,362
Filed by SIGNIFY HOLDING B.V., Eindhoven (NL)
PCT Filed May 20, 2021, PCT No. PCT/EP2021/063420
§ 371(c)(1), (2) Date Oct. 29, 2022,
PCT Pub. No. WO2021/234070, PCT Pub. Date Nov. 25, 2021.
Claims priority of application No. PCT/CN2020/091564 (WO), filed on May 21, 2020; and application No. 20191285 (EP), filed on Aug. 17, 2020.
Prior Publication US 2023/0180365 A1, Jun. 8, 2023
Int. Cl. H05B 45/3725 (2020.01); H05B 45/59 (2022.01)
CPC H05B 45/3725 (2020.01) [H05B 45/59 (2022.01)] 15 Claims
OG exemplary drawing
 
1. A driving circuit comprising:
a converter comprising:
an input to receive a supply voltage with a cyclic ripple having peak portions and valley portions;
a switch mode power converter circuit to convert the supply voltage, including an energy storage component and a main control switch;
an output; and
a current sensor for sensing an output current delivered at the output and generating a sensed current signal;
a control circuit to control a switching of the main control switch of the converter circuit, wherein the energy storage components is adapted to discharge to provide a regulated DC current at the output upon the switching of the main control switch; and
a modulation circuitry to apply a time-varying offset to the control circuit to modulate the regulated current thereby controlling the voltage across the energy storage component, wherein the modulation circuit comprises a ramp circuit for generating a time-varying ramp signal for combination with a static reference current signal to generate a modulated reference current signal and the control circuit comprises a comparator circuit for comparing the sensed current signal with the modulated reference current signal and an output of the comparator is for providing a current feedback signal for the control circuit so that the time-varying offset is adapted to ensure a margin of the voltage across the energy storage component above the supply voltage.