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IDENTIFY THE ANODE/CATHODE of LED's
While referring to any schematic involving led's we sometimes get confused with the identification of the terminals. So for identification , led’s comes with a unique way to identify its terminals as Anode or Cathode. Sometime the diode symbol creates confusion too.Identifing a LED's the cathode and anode of a led is very easy by looking inside.
LED's or Light Emitting Diode's don’t come with any labeling on it to identify Cathode(-ve,GND) or Anode(+ve).
I hope the figure below can solve this problem of identification.
Notice the picture carefully and compare it with the LED diode symbol, that should tell which one is –ve and +ve terminal. As they have to be crystall clear to glow so they don’t have any labeling on it , so the only way to know is either to test it with a multimeter or by carefully observing inside the led . The larger end inside the led is -ve and the shorter one is +ve, that is how we find out the polarity of a LED
Save this picture for reference.
NOTE: I took this picture myself from my camera , Please Do not mind for image clarity ,so i have put some labellings also .
THANKS FOR READING
Rakesh Ron
www.rakeshmandal.info
CATHODE AND ANODE OF LED
******************************************************************************
While referring to any schematic involving led's we sometimes get confused with the identification of the terminals. So for identification , led’s comes with a unique way to identify its terminals as Anode or Cathode. Sometime the diode symbol creates confusion too.Identifing a LED's the cathode and anode of a led is very easy by looking inside.
LED's or Light Emitting Diode's don’t come with any labeling on it to identify Cathode(-ve,GND) or Anode(+ve).
I hope the figure below can solve this problem of identification.
Notice the picture carefully and compare it with the LED diode symbol, that should tell which one is –ve and +ve terminal. As they have to be crystall clear to glow so they don’t have any labeling on it , so the only way to know is either to test it with a multimeter or by carefully observing inside the led . The larger end inside the led is -ve and the shorter one is +ve, that is how we find out the polarity of a LED
Save this picture for reference.
NOTE: I took this picture myself from my camera , Please Do not mind for image clarity ,so i have put some labellings also .
THANKS FOR READING
Rakesh Ron
www.rakeshmandal.info
CATHODE AND ANODE OF LED
******************************************************************************
Thanks for the info. Sometimes manufacturers tend to NOT use industry standards and switch the Anode/Cathode leads around from the flat side or the leads are the same length, making it hard to decipher which is which. This will help in not blowing out unknown LED's.
Qa
you are right if its not some exceptional case, but most of the time this markings works just fine ( if the manufacturers follow Industry std) :) but in case if it not according to industry std , then i recommend always to use a multimeter as final touch up to ensure the polarity of led's :)
Thanks for the info :)
ron
I have not come across this and I am really interested to know which ones.
Another situation where this could come in handy is when reusing LED's from existiing projects where the "ledge" was ground off (I saw that a long time ago) and the leads were already trimmed.
It is still valuable to know the construction of the LED so that if you have any question as to which lead is the Anode or Cathode, you can tell by looking at the inside.
Qa