TRIAC LED Driver Packs Full-Range, Flicker-Free Dimming

Oct. 8, 2008
Promising to extend LED life via a patent-pending control architecture, the LM3445 TRIode for alternating current (TRIAC) dimmable LED driver enables off-line, uniform flicker-free dimming of high-brightness LEDs with a conventional TRIAC forward or

Promising to extend LED life via a patent-pending control architecture, the LM3445 TRIode for alternating current (TRIAC) dimmable LED driver enables off-line, uniform flicker-free dimming of high-brightness LEDs with a conventional TRIAC forward or reverse phase-control wall dimmer. It allows for a full 100:1 range of dimming and can maintain greater than 1A of constant current to large strings of LEDs. It also allows master-slave operation, enabling control of multiple strings of LED bulbs. Residing in a 10-pin mini SOIC package, the device is an adaptive constant off-time ac/dc buck constant current controller that includes a TRIAC dimming decoder. It includes a bleeder circuit to ensure proper TRIAC operation by allowing current flow while the line voltage is low to enable proper firing of the TRIAC. A passive power factor correction circuit ensures reliable power factor by drawing current directly from the line for most of the cycle and provides a constant positive voltage to the buck regulator. Additional features include thermal shutdown, current limit, and under-voltage lockout. The LM3445 is available now for $1.75 each/1,000. NATIONAL SEMICONDUCTOR CORP., Santa Clara, CA. (800) 272-9959.

Company: NATIONAL SEMICONDUCTOR CORP.

Product URL: Click here for more information

About the Author

Staff

Articles, galleries, and recent work by members of Electronic Design's editorial staff.

Sponsored Recommendations

Comments

To join the conversation, and become an exclusive member of Electronic Design, create an account today!