TRIAC LED driver enables both full-range and flicker-free dimming

TRIAC LED driver enables both full-range and flicker-free dimming

Part enables direct LED bulb replacement of existing incandescent or halogen bulb systems connected to standard TRIAC wall dimmers

The LM3445 is offered as the first TRIAC dimmable LED driver to offer off-line, uniform, flicker-free dimming of high-brightness LEDs with a conventional TRIode for Alternating Current (TRIAC) forward or reverse phase-control wall dimmer. The part enables a full 100:1 range of dimming capability and can maintain greater than 1 A of constant current to large strings of LEDs in a variety of residential, architectural, commercial, and industrial applications.

Today’s TRIAC wall dimmers are designed to interface with a resistive load such as incandescent or halogen light bulbs, so dimming an LED bulb using a conventional TRIAC wall dimmer does not yield optimal dimming performance. While current LED drivers cause either a 120-Hz flicker of the LEDs or do not enable the full 100:1 dimming range, the LM3445 overcomes this challenge by translating the TRIAC-chopped waveform to a DIM signal and decoding it for a full-range of uniform, flicker-free dimming.

Offered in a 10-pin mini SOIC package, the LM3445 includes a bleeder circuit and a passive power factor correction circuit Additional features include thermal shutdown, current limit, and undervoltage lockout. ($1.75 ea/1,000 — available now.)

National Semiconductor , Santa Clara , CA
Sales 800-272-9959

http://www.national.com