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Measuring Voltage of LED


JWW

#28837

Measuring Voltage of LED | 30 May, 2004

Hi Everyone,

I have a number of LED's of different voltages. Would someone please tell me how I can measure the voltage of each LED so I don't apply the wrong voltage and burn them out.

Thanks.

JW

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snmsmt

#28838

Measuring Voltage of LED | 30 May, 2004

I assume your talking about the forward voltage (Vf) of the LED during operation? (Probably not the correct forum for this question but anyway...)

My understanding is that 'Vf' is measured during the LED's operation at a forward current ('If') of 20mA. Given that you should simply be able to connect up a test circuit and using 2 DMM's, set 'If' too 20mA then measure 'Vf' across the LED A & K no?

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JAArient

#31052

Measuring Voltage of LED | 21 October, 2004

If you are measuring the voltage for a presence test that is fine. But you can not tell you the color of the led and have confidence that the right part is installed. Led forward voltages vary a lot between parts and between mfgs also. http://www.TestCoach.Com makes led color and light intensity testing products.

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