Driver dims LED off a normal switch

July 19, 2012 // By Christoph Hammerschmidt
O2Micro International Ltd, unveiled a new dimming architecture for the global LED lighting market. The company's patented Free Dimming technology enables LED bulbs to dim using any on/off switch, thus eliminating the burden of installing expensive dimmers. O2Micro claims the technology works with any on/off switch, including wall toggles, paddle switches, pull cords, rotary switches and other types of on/off switches commonly found on walls, extension cords and table/desk lamps.

According to industry estimates, there are roughly 150 million incandescent dimmers installed in the USA alone. In theory, LED bulbs are fully dimmable; however, designing them to be compatible with incandescent dimmers is challenging. Such designs add significant complexity and cost to the LED bulb, reduce efficiency, and often result in poor performance that leads to product returns and potential safety issues.

Chronic compatibility and performance issues include aesthetic problems such as flicker, audible hum, “jumpy” dimming, and poor turn-off performance. Others are various electrical issues such as inrush current, which stresses components in both the dimmer and LED bulb, shortening product lifetime and creating safety issues. Furthermore, support for legacy incandescent dimmers does not address the more than 85% of light bulbs that operate from non-dimming on/off switches. Although there are 150 million incandescent dimmers installed in the USA alone, according to the National Electrical Manufacturers Association (NEMA), there are over 4.4 billion medium, screw-based light sockets in the US, representing an enormous, untapped market opportunity.

Amidst these towering questions, O2Micro says it has the answer. The Free Dimming LED driver product family is inherently simple and works with any non-dimming on/off switch. It has broad appeal, working with the more than 85% of lights that are on non-dimming circuits. For consumers, eliminating dimmer cost and installation makes LED bulbs that incorporate O2Micro's Free Dimming LED driver easy to use and a great value.

For LED bulb manufacturers, O2Micro's Free Dimming LED drivers shift dimming from a cost burden to a profit enhancer by enabling them to expand their addressable market by capturing dimmer revenue that would normally be served by dimmer manufacturers. O2Micro's Free Dimming LED drivers offer the lowest BOM cost with the smallest footprint and have higher efficiency than incandescent dimming drivers by eliminating excess circuitry required to make LED bulbs work with incandescent dimmers. 

The products in O2Micro's Free Dimming LED driver product family, the