Light at the end of the tunnel

Solid state lighting is one area that seems to be growing in a gloomy economic scene. Making the most of LED lighting can create real savings for purchasing managers, says lighting business manager, Anglia Components, Dan Scott
Technology is evolving fast in LED lighting and there is an opportunity for purchasing managers to achieve cost of acquisition and cost of ownership savings by investing in new lighting platforms. Only buyers who form long term partnerships with suppliers who understand this fast moving area will be able to make the most of the rapid progress that is being made.

See the light
The LED market currently represents an attractive prospect as it is growing considerably, offering the end customer reduced maintenance, improved efficiencies and increased lifetime.
An LED is essentially a semiconductor product. The majority of LED manufacturers buy the die in and package it in different forms, yet the packaging itself can have a significant impact on performance. For example, LED lifetime, maintained brightness and colour stability vary depending on how much heat is created and removed from the package.
LED availability and pricing is thus affected by what is happening elsewhere in the semiconductor industry. As general chip availability pushes out, we see the same trend in LEDs, with high power LEDs over one Watt going out to eight to ten weeks and lower power devices to six to eight weeks.
There is currently something of an arms race in progress amongst LED manufacturers with LED lamps that are brighter and/or more efficient emerging every few months. In terms of pricing, the latest products command a premium, but this tails off as the industry moves ahead and in general, market price continues to fall, allowing the end customer to produce more light for less cost.
If youve been specifying the same LED lamp for a number of years, it is worth reviewing it to see if a lower cost, more efficient device is available that matches or exceeds the performance of your current part.
Changing the LED can involve a board redesign which ultimately creates cost unless youve selected a vendor with a standard LED footprint. This also protects against obsolescence, which is inevitable since manufacturers will eventually withdraw the oldest, least efficient chips.

Be specific
A close relationship with your LED supplier is key to solving the challenges of specifying LEDs. Colour binning provides a good example. Most manufacturers have multiple different shades, or bins, of their standard white or coloured LEDs. These bins are created by measuring the spectrum of the light emitted by each LED after manufacture and sorting them accordingly.
Depending on their objectives, customers may or may not be willing to accept LEDs from different bins. For example, a contractor lighting a fleet of coaches may decide that each coach must be supplied from the same bin, but it’s OK to supply a different coach from a different bin. In sensitive applications, it is important to place a scheduled order to minimise variations in colour and brightness.

Supplier selection
Selecting the right LED supplier is clearly a strategic decision. In addition to the technical expertise of the field support staff, it is worth looking for a supplier with an electronics lab that can help with the task of designing LED light engines.
Suppliers should also have a good understanding of the LED market, with the ability to work with you beyond the design process, through the whole lifecycle of the product, alerting you to forthcoming obsolescence and to opportunities to introduce more efficient solutions that help keep you competitive.