Table 1 (below) lists a general process for designing high-power LEDs into a luminaire. The rest of the document walks through these design steps in order. To better illustrate these design concepts, this document includes example calculations for an LED luminaire meant to replace a 23-W CFL downlight. This design process is repeatable for all kinds of luminaires and not just the example included.
Step |
Explanation |
Define lighting requirements |
- The design goals should be based either on an existing fixture’s performance or on the application’s lighting requirements.
|
Define design goals |
- Specify design goals, which will be based on the application’s lighting requirements.
- The designer should specify any other goals that will influence the design, such as special optical requirements or being able to withstand high temperatures.
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Estimate efficiencies of the optical, thermal & electrical systems |
- Design goals will place constraints on the optical, thermal and electrical systems.
- Good estimations of efficiencies of each system can be made based on these constraints.
- The combination of lighting goals and system effiiciencies will drive the number of LEDs needed in the luminaire.
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Calculate the number of LEDs needed
|
- Based on the design goals and estimated losses, the designer can calculate the number of LEDs needed to meet the design goals.
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Consider all design possibilities and choose the best |
- As with any design, there are many different ways to best achieve the design goals.
- LED lighting is still a new field, so assumptions that work for conventional lighting sources may not apply to LED lighting design.
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Complete final steps |
- Complete circuit board layout.
- Test design choices by building a prototype luminaire.
- Make sure the design achieves all the design goals.
- Use the prototype design to further refine the luminaire design.
- Record observations and ideas for improvement.
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