US 12,336,069 B2
Constant-current switch-mode power converters for LED lighting and methods thereof
Liqiang Zhu, Shanghai (CN); and Lieyi Fang, Shanghai (CN)
Assigned to On-Bright Electronics (Shanghai) Co., Ltd., Shanghai (CN)
Filed by ON-BRIGHT ELECTRONICS (SHANGHAI) CO., LTD., Shanghai (CN)
Filed on Jul. 14, 2023, as Appl. No. 18/222,417.
Claims priority of application No. 202210545406.2 (CN), filed on May 19, 2022.
Prior Publication US 2025/0024571 A1, Jan. 16, 2025
Int. Cl. H05B 45/3725 (2020.01)
CPC H05B 45/3725 (2020.01) 23 Claims
OG exemplary drawing
 
1. A controller for a constant-current switch-mode power converter, the controller comprising:
a constant-current controller configured to receive an input voltage and generate a modulation signal based at least in part on the input voltage; and
a driver configured to receive the modulation signal, generate a drive signal based at least in part on the modulation signal, and output the drive signal to a transistor coupled to an inductive coil and a resistor;
wherein:
the drive signal corresponds to at least one switching cycle;
the switching cycle includes an on-time during which the drive signal is at a first logic level and an off-time during which the drive signal is at a second logic level; and
the off-time includes a demagnetization period during which the inductive coil undergoes a demagnetization process;
wherein:
the constant-current controller includes a reference voltage generator configured to receive the input voltage and generate a reference voltage based at least in part on the input voltage; and
the reference voltage is equal to the input voltage multiplied by a ratio of the on-time to a sum of the on-time and the demagnetization period.