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3 pronged LED Answered

I just bought some bipolar LED's from a local store. When I opened the bag, I realized that each LED had 3 prongs instead of the usual 2 prongs. How do I use it? Is the middle prong the positive or negative side?


With the common anode type it would connect (through a resistor) to the positive leg of the circuit, and the path through one cathode or the other is determined by the load. With a common cathode, the switching will occur on the positive leg.

. Depends. I quick search for 'bipolar LED +"3 lead" ' shows common-cathode and common-anode LEDs. A diode checker should tell you.