Anglia Lighting LED Solid State Lighting

CREE Led Light Design Process

LED Design Guide  

Click on the links below to follow the Cree Luminaire Design Guide.

Design Process

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.



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.

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.

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.

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.

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.

Table 1 - Process for Designing High-Power LEDs into Luminaires

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