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To determine a LED max current

audioguru

Well-Known Member
Most Helpful Member
Most electronic parts have ratings that are minimum, typical and maximum. If you buy 100 of the same part number and when testing, slowly turn up the current then some of them will quickly burn out, some will get very hot but survive and some will be fine.
All half-decent electronic parts have a datasheet that has maximum do not exceed current ratings. Do not operate parts at or exceed the ratings.
 

alec_t

Well-Known Member
Most Helpful Member
Welcome to ETO!
How do we determine a LED max current by some tests?
Cautiously, by increasing the current through it gradually until it fails. Failure may involve heat and flame; hence the caution.
However, as AG implies, no two LEDs are identical, so measuring the max current for one won't guarantee that the rest of your LEDs (even from the same batch) have the same characteristic. The moral is: read the datasheet for any component you intend to use.
 

ronsimpson

Well-Known Member
Most Helpful Member
LEDs; may last hours at 120% power but will not last years. LEDs get dim with over current and time. This depends on what color/type of LED. You really need a data sheet. Temperature rise is hard on LEDs. Yours might be too small to get a good temperature reading. I an certain you do not want to wait a year to see how much current effects light output with time.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
LEDs; may last hours at 120% power but will not last years. LEDs get dim with over current and time. This depends on what color/type of LED. You really need a data sheet. Temperature rise is hard on LEDs. Yours might be too small to get a good temperature reading. I an certain you do not want to wait a year to see how much current effects light output with time.

Hence the crappy LG TV panels (used by various manufacturers, including LG and Samsung), they considerably reduced the number of LED's used (cost 'improved'), and fitted plastic lenses over them, the result is they get far too hot, destroy the phosphor in the LED's that makes them white giving purple patches on the picture. In worse case the plastic lenses fall off, and rattle round the bottom of the panel.

At least in the UK you're protected by what used to called the 'Sale Of Goods Act', and you can claim against the retailer for a repair, a new set, or your money back - but many don't even last the 12 month warranty.
 

danadak

Active Member
There are many considerations and testing/device characterization/process characterization
that go into parts to make them reliable when shipped.

So if you care about product lifetime, reliability, your reputation as a manufacturer, stick to datasheet
and legitimately sourced components.


Regards, Dana.





Regards, Dana.
 

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