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LED failures: How to stop them dead

LED failures: How to stop them dead. LED failures: How to stop them dead David Scott-Maxwell Technical Director, Forge Europa. LED failures: How to stop them dead. Before we start – what are ‘LEDs’?:. LED failures: How to stop them dead. Before we start – these are ‘LEDs’:.

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LED failures: How to stop them dead

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  1. LED failures: How to stop them dead • LED failures: How to stop them dead • David Scott-Maxwell • Technical Director, Forge Europa

  2. LED failures: How to stop them dead • Before we start – what are ‘LEDs’?:

  3. LED failures: How to stop them dead • Before we start – these are ‘LEDs’:

  4. LED failures: How to stop them dead • Before we start – these are ‘LEDs’: • ‘LEDs’ ARE NOT MUCH USE ON THEIR OWN!

  5. LED failures: How to stop them dead • Before we start – ‘LED failures’ = ‘Whole system failures’

  6. LED failures: How to stop them dead • Before we start – ‘LED failures’ = ‘Whole system failures’

  7. LED failures: How to stop them dead • What’s in a ‘Whole system’?

  8. LED failures: How to stop them dead • What’s in a ‘Whole system’?

  9. LED failures: How to stop them dead • What’s in a ‘Whole system’? • LED

  10. LED failures: How to stop them dead • What’s in a ‘Whole system’? • LED • PCB

  11. LED failures: How to stop them dead • What’s in a ‘Whole system’? • LED • PCB • Heatsink

  12. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Driver/PSU • LED • PCB • Heatsink

  13. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Driver/PSU • LED • PCB • Enclosure • Heatsink

  14. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Optics • Driver/PSU • LED • PCB • Enclosure • Heatsink

  15. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Optics • Driver/PSU • LED • Adhesives • TIMs • etc • PCB • Enclosure • Heatsink

  16. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Optics • Driver/PSU • LED • Adhesives • TIMs • etc • PCB • Enclosure • Heatsink • Testing

  17. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Optics • Driver/PSU • LED • Adhesives • TIMs • etc • PCB • Enclosure • Heatsink • Testing • Packaging

  18. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Optics • The user! • Driver/PSU • LED • Adhesives • TIMs • etc • PCB • Enclosure • Heatsink • Testing • Packaging

  19. LED failures: How to stop them dead • What’s in a ‘Whole system’? • Optics • The user! • Driver/PSU • LED • Adhesives • TIMs • etc • PCB • Enclosure • Heatsink • Testing • Packaging

  20. LED failures: How to stop them dead • LED failures:

  21. LED failures: How to stop them dead • LED failures: • Electrical Overstress (EOS) • Overheat • Chemical Contamination • Electrostatic Discharge (ESD)

  22. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  23. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  24. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  25. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  26. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  27. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  28. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverseconnection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  29. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, educate

  30. LED failures: How to stop them dead • LED failures: Electrical Overstress (EOS) • Causes • ‘Hot Plugging’ #1 LED killer - VERY easily done! • …during in-factory test, luminaire installation • …can be latent • Reverse connection • Effects • Lights out (often short circuit) • Prevention • BE EOS AWARE, design-in circuit protection, lock down factory procedures, Educate

  31. LED failures: How to stop them dead • LED failures: Overheat • Causes • Modern Lighting Class LEDs can run HOT… • …but there’s a limit to how much power they can handle • …and adequate heatsinking must be provided • …and users can/will overheat products • Effects • Reduced lifetime [LM80/TM21], colour shift • Prevention • Heatsinkdesign is tough – don’t underestimate • Educate customers

  32. LED failures: How to stop them dead • LED failures: Overheat • Causes • Modern Lighting Class LEDs can run HOT… • …but there’s a limit to how much power they can handle • …and adequate heatsinking must be provided • …and users can/will overheat products • Effects • Reduced lifetime [LM80/TM21], colour shift • Prevention • Heatsinkdesign is tough – don’t underestimate • Educate customers • XM-L / 105° / 2A • L70>70khrs

  33. LED failures: How to stop them dead • LED failures: Overheat • Causes • Modern Lighting Class LEDs can run HOT… • …but there’s a limit to how much power they can handle • …and adequate heatsinkingmust be provided • …and users can/will overheat products • Effects • Reduced lifetime [LM80/TM21], colour shift • Prevention • Heatsinkdesign is tough – don’t underestimate • Educate customers

  34. LED failures: How to stop them dead • LED failures: Overheat • Causes • Modern Lighting Class LEDs can run HOT… • …but there’s a limit to how much power they can handle • …and adequate heatsinking must be provided • …and userscan/will overheat products • Effects • Reduced lifetime [LM80/TM21], colour shift • Prevention • Heatsinkdesign is tough – don’t underestimate • Educate customers

  35. LED failures: How to stop them dead • LED failures: Overheat • Causes • Modern Lighting Class LEDs can run HOT… • …but there’s a limit to how much power they can handle • …and adequate heatsinking must be provided • …and users can/will overheat products • Effects • Reduced lifetime [LM80/TM21], colour shift • Prevention • Heatsinkdesign is tough – don’t underestimate • Educate customers

  36. LED failures: How to stop them dead • LED failures: Overheat • Causes • Modern Lighting Class LEDs can run HOT… • …but there’s a limit to how much power they can handle • …and adequate heatsinking must be provided • …and users can/will overheat products • Effects • Reduced lifetime [LM80/TM21], colour shift • Prevention • Heatsinkdesign is tough – don’t underestimate • Educate customers

  37. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  38. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  39. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  40. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  41. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  42. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  43. LED failures: How to stop them dead • LED failures: Chemical Contamination • Causes • Silicones particularly vulnerable to ‘charring’ • LED manufacturer’s black lists & white lists • Sometimes reversible, sometimes not… • Effects • Reduced lifetime, colour shift • Prevention • Check the lists, do your own tests, be aware of ‘hidden’ chemical usage.

  44. LED failures: How to stop them dead • LED failures: Electrostatic Discharge • Causes • Rare due to protected LED components, • good ESD handling, protection via circuitry • BUT - can be latent… • Effects • Lights out • Prevention • Install & audit ESD handling procedures, design-in circuit protection

  45. LED failures: How to stop them dead • LED failures: Electrostatic Discharge • Causes • Rare due to protected LED components, • good ESD handling, protection via circuitry • BUT - can be latent… • Effects • Lights out • Prevention • Install & audit ESD handling procedures, design-in circuit protection

  46. LED failures: How to stop them dead • LED failures: Electrostatic Discharge • Causes • Rare due to protected LED components, • good ESD handling, protection via circuitry • BUT - can be latent… • Effects • Lights out • Prevention • Install & audit ESD handling procedures, design-in circuit protection

  47. LED failures: How to stop them dead • Driver/PSU failures: • Electronic product reliability • Key component lifetime • Soldering

  48. LED failures: How to stop them dead • Driver/PSUfailures: Electronic Product Reliability • Electronic products canbe extremely reliable! • … but ‘you gets what you pays for’… • ‘0.2%/1000hrs’ de-facto standard for lighting electronics

  49. LED failures: How to stop them dead • Driver/PSUfailures: Electronic Product Reliability • Electronic products can be extremely reliable! • … but ‘you gets what you pays for’… • ‘0.2%/1000hrs’ de-facto standard for lighting electronics

  50. LED failures: How to stop them dead • Driver/PSUfailures: Key Component Lifetime • Causes • Electrolytic capacitors • Freewheel diodes • Bridge rectifiers • Optocouplers • … etcetc … • Effects • Lights out, flickering, EMC non-compliance, … • Prevention • Design for product lifetime, control manufacturing

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