Power LEDs are the class where the package exists to move heat away from the die, not merely to enclose it. That single difference is what separates this class from the signal and indicator parts: a power LED is specified by its forward current, its thermal path and its junction temperature limit, and reading it any other way produces a design that fails in the luminaire rather than on the bench.

Two families are documented here. The ceramic package range is the larger and is covered in five pages of its own. Automotive exterior lighting is a separate page because it turns on a qualification standard rather than on a thermal or optical characteristic.

1. What is in this section

  • Ceramic LEDs
    Five pages covering the ceramic package range end to end: what the substrate changes, what the ratings are, how to read the characteristics, how to assemble and protect the parts, and how to choose a part number.
  • Automotive LED AEC-Q102
    Exterior lighting qualification: what AEC-Q102 tests, which parts of it apply to a given design, and what it does not cover.

2. Where to start

If you are choosing a power LED for a luminaire, read the selection guide first — it reduces the range to four questions and lands on a footprint class. If you are checking whether a part will survive the assembly, go to reliability and soldering. If you are specifying a value that has to be defensible, the ratings page is where every limit is stated.

For automotive exterior lighting the order is different, because the qualification precedes the electrical choice: confirm what the standard requires, then select within it.

3. Three things that are commonly misunderstood

  • Package size does not set the current. The current ceiling is set by the die count and the drive voltage inside the package, not by the outline. Two parts in the same footprint can differ by a factor of two in flux.
  • Absolute maximum is not an operating point. A rating tells you the failure boundary. Where to actually run is decided by the thermal budget, not by the rating.
  • Forward voltage is not a single number. It depends on the die configuration and, in the colour families, on the colour itself. See the characteristics page before assuming a rail voltage.

4. Why this class is separate

Power LEDs are separated from the rest of the catalogue because their failure modes are different in kind, not in degree. A signal LED fails as an open or a short and the circuit stops working. A power LED fails by exceeding its junction temperature, which is a gradual process that shows up as reduced output long before the part stops emitting. That difference is what makes the thermal design part of the component specification rather than part of the fixture design.

It is also why the pages in this class carry more constraint information than a catalogue normally would. The ratings are stated per die configuration rather than per package, the assembled process is bounded, and the reliability data has to be requested for the specific part number. A designer who treats a power LED like a general-purpose indicator part will find that the data needed to close the design simply is not on the page.