A Novel Dimming Approach for Both TRIAC and Wall Switch LED Lighting Systems

Triode alternating current (TRIAC) and wall switch step dimming are the most common methods for adjusting brightness of incandescent lighting sources. However, the gradual replacement of incandescent bulbs with light-emitting diode (LED) bulbs has made it necessary to integrate dimming methodologies within the LED driver. This paper presents the design, simulation, and implementation of a LED driver circuit capable of dimming functionality using either TRIAC or a wall switch. The simulation circuits are based on LT3799 and LTspice (Linear Technology). Experiments conducted using a 110V AC input under a 20W LED load connected in series demonstrate the efficacy of the proposed system when operating with TRIAC dimmers as well as wall switches.