The industry is ready for the year of the diode, writes Doug Bailey, v-p marketing at Power Integrations
The emergence of solid state lighting has been discussed in the technical media, at trade shows and in labs for almost a decade. Many of the initial technical challenges have been solved – driving LEDs efficiently, heat management in retrofit LED bulb designs and circuit strategies to ensure reliability and longevity, to name a few. Yet the technology is only now approaching universal acceptance as a valid choice for businesses and home owners.
The outcomes of deployments have been mixed, with the large numbers of unit shipments to retail establishments and hotels contrasting with negative experiences in China – where many LED streetlights failed only months after installation. My opinion is that 2012 will be the year when the technology matures and the hidden revolution in lighting becomes public. The reach of LED lighting will extend beyond the specialists and early adopters and into the consumer mainstream.
In 2011 we saw the early signals of a tipping point in favour of LED lighting, accelerated by stresses on the Japanese electrical grid caused by the tragic earthquake and tsunami. Due to the high efficacy of LED lights, Japanese consumers and businesses have adopted the technology as a key contributor to the country’s energy management strategy.
Of course, the need to conserve power in the aftermath of the disaster was manifestly obvious, but also there was, and remains, a need for re-construction on a huge scale. This has resulted in a huge expansion of LED lighting production which is having a knock-on effect in reducing prices worldwide. Furthermore, Asian investments in material precursors such as sapphire wafers and also in LED production, coupled with a slower than expected ramp of LED TVs, have combined to further depress the prices of the LEDs themselves and increased the marketability of the technology for general lighting.
One other significant development for the company was our move into the discrete diode business. The humble diode (initially demonstrated in 1874) was the first commercially relevant rectifier device and it’s easy to suppose that development must have reached some kind of plateau by now. However, it’s not so easy to ignore the contribution that this pervasive component makes to energy loss and conversely, therefore, opportunities to make substantial efficiency gains.
Both our Qspeed Merged PIN-Schottky rectifiers and SemiSouth’s Silicon Carbide diodes (that we sell) permit the manufacture of power factor correction circuits and AC inverters approaching 98% and 99% efficiency respectively. Efficiency gains enabled by use of advanced diodes will become more important as photo-voltaic solar energy installations, UPS systems and vehicle chargers increase their adoption in a world hungry for green energy and transportation. Designers versed in the subtle trade-offs between diode types can take advantage of the benefits that they bring to achieve new levels of efficiency or to reduce overall system cost, size, weight and complexity.
With an increase in the pace of development, utility and relevance of the diode – light emitting and otherwise – to the daily lives of people everywhere, it’s my expectation that 2012 be the year of the diode, just 138 years since its invention.