US 12,408,248 B2
LED power supply
Ching-Ho Chou, Taoyuan (TW); and Yung-Chuan Lu, Taoyuan (TW)
Assigned to Delta Electronics, Inc., Taoyuan (TW)
Filed by Delta Electronics, Inc., Taoyuan (TW)
Filed on Dec. 28, 2023, as Appl. No. 18/398,364.
Claims priority of application No. 202310744025.1 (CN), filed on Jun. 21, 2023; and application No. 202311321409.9 (CN), filed on Oct. 12, 2023.
Prior Publication US 2024/0430999 A1, Dec. 26, 2024
Int. Cl. H05B 45/37 (2020.01); H05B 45/14 (2020.01); H05B 45/50 (2022.01)
CPC H05B 45/37 (2020.01) [H05B 45/14 (2020.01); H05B 45/50 (2020.01)] 13 Claims
OG exemplary drawing
 
1. An LED (light-emitting diode) power supply, adopting constant-voltage/constant-current control, configured to supply power to an LED device, and comprising:
an input terminal and an output terminal;
an isolated DC-DC conversion circuit, having a primary side and a secondary side electrically connected to the input terminal and the output terminal respectively, and configured to receive an input voltage from the input terminal and provide an output voltage to the output terminal; and
a control module, comprising:
a first control unit, electrically connected to the primary side and configured to control operation of the isolated DC-DC conversion circuit;
a feedback circuit, electrically connected to the output voltage, and comprising a first resistor, a first diode and a second resistor electrically connected in series;
a first switch, electrically connected to the feedback circuit;
a second switch, electrically connected to the first switch; and
an optocoupler, configured for signal transmission with electrical isolation, and comprising a transmitter and a receiver electrically connected to the secondary side and the first control unit respectively;
wherein when the output voltage is lower than a threshold voltage, the first switch is turned off, the second switch is turned on to trigger the optocoupler to generate a trigger signal at the receiver, and the first control unit controls the isolated DC-DC conversion circuit to stop operating based on the trigger signal.