Open AccessHigh‐efficiency multi‐string LED driver based on constant current bus with time‐multiplexing control
Author(s) -
Liu Xueshan,
Xu Jianping,
Yang Qi,
Xu Duo
Publication year - 2016
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2016.0236
Subject(s) - constant current , string (physics) , current (fluid) , capacitor , multiplexing , electrical engineering , engineering , led circuit , filter (signal processing) , constant (computer programming) , electronic engineering , computer science , control theory (sociology) , voltage , physics , control (management) , short circuit , quantum mechanics , artificial intelligence , programming language
A high‐efficiency multi‐string LED driver based on constant current bus with time‐multiplexing control scheme is proposed and analysed. Each LED string is connected to the constant current bus, which is provided by the output of a front‐end high‐efficiency converter. The current of each LED string can be independently controlled by the turn on duty ratio of its time‐multiplexing switch. A capacitor is connected to the current bus to provide a current flowing path for constant bus current when none of the LED string is connected to the current bus. It needs only one output filter capacitor, which makes circuit volume small and cost low. Finally, a 7.2 W two‐string LED driver is provided to verify the studied results.