T
treez
Guest
This concerns this thread from some time back....
https://www.edaboard.com/threads/352771/
https://www.edaboard.com/threads/352771/
This quote is from post number #49 of the above thread.But what we dont know is how they do ORT and how do they know how much margin exists in shearing the Anode connection with the ultrasonically cold-welded micron size gold wire. THIS IS THE MOST COMMON failure mode in LEDs. It can occur for many reasons. Some designs use dual wire bond. But all must survive the extreme thermal stress from different coefficients of material expansion not get "wounded" from shock, vibration, ESD, thermal shock, transient overpower etc etc.
…Thanks…and WOW!!!.....that is ground-breaking, and blows out of the water all the research in to finding ways of being abe to handle mains transients in order to get long-life.
By the way, do you have a paper on that?
We are now wanting to do long life outdoor street lighting.
If there is some issue with bond wires to LED substrate having to be ridiculously thin, and often, as you appear to suggest, it gets cut too thin due to machine tolerance, and that causes LED failure in the field, then there’s not much point in us investing more time in finding ways of surviving every possible mains transient that present itself to the street lights………since the bond wire issue that you speak of is going to give us failures even if we do the best ever transient protection?
Are you sure its the main cause of failure in LED lamps?