Title :
A new TRIAC dimmable LED driver control method achieves high-PF and quality-of-light
Author :
Yan, Liang ; Chen, Baorong ; Zheng, Jerry
Author_Institution :
iWatt Inc., Los Gatos, CA, USA
Abstract :
TRIAC dimmable LED driver senses the input phase or RMS voltage to determine the dimming current level. Most TRIAC dimmable LED drivers use bleeding circuits to help supply enough holding current in order to keep the TRIAC on. This usually adds extra power devices and control circuits to the bleeding circuit. This paper proposes a new dimming approach that allows the dimmer to turn off if the dimmer current drops below the holding threshold. The input capacitance is actively discharged by the boost circuit. The boost operation restores the input phase without keeping the TRIAC conduction. Therefore it avoids the multi-firing and dimmer turn-off inconsistency. Both the bleeding and holding functions are integrated into the boost circuit.
Keywords :
capacitance; driver circuits; light emitting diodes; RMS voltage; TRIAC conduction; TRIAC dimmable LED driver control method; bleeding circuit; bleeding function; boost circuit; boost operation; control circuit; dimming current level; high-PF; holding current; holding function; holding threshold; input capacitance; power device; quality-of-light; Capacitors; Hemorrhaging; Light emitting diodes; Reactive power; Shape; Switches; Thyristors;
Conference_Titel :
Applied Power Electronics Conference and Exposition (APEC), 2012 Twenty-Seventh Annual IEEE
Conference_Location :
Orlando, FL
Print_ISBN :
978-1-4577-1215-9
Electronic_ISBN :
978-1-4577-1214-2
DOI :
10.1109/APEC.2012.6165936