US Patent No. 10,433,384

LED DRIVER WITH SILICON CONTROLLED DIMMER, APPARATUS AND CONTROL METHOD THEREOF


Patent No. 10,433,384
Issue Date October 01, 2019
Title Led Driver With Silicon Controlled Dimmer, Apparatus And Control Method Thereof
Inventorship Qiukai Huang, Hangzhou (CN)
Jianxin Wang, Hangzhou (CN)
Huiqiang Chen, Hangzhou (CN)
Assignee Silergy Semiconductor Technology (Hangzhou) LTD, Hangzhou (CN)

Claim of US Patent No. 10,433,384

1. An apparatus, comprising:a) a bleeder circuit coupled between a DC bus of a light-emitting diode (LED) driver having a silicon-controlled dimmer, and an LED driving sub-circuit having an LED load and a first transistor coupled in series;
b) a controller configured to control, when said silicon-controlled dimmer is off, said bleeder circuit to control a voltage of said DC bus that is generated across two output terminals of a rectifier bridge, wherein said rectifier bridge is coupled to said silicon-controlled dimmer, and said DC bus voltage is configured to provide a load driving voltage to said LED load; and
c) said bleeder circuit being configured to control said DC bus voltage to be approximate to a predetermined load driving voltage that is said load driving voltage when said silicon-controlled dimmer conducts at a maximum conduction angle.