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Led in Series problem

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AinaLaw

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Dear All

I have a problem with my Led project.

The schematic is :
12V - 78M09 - R 1ohm - Led1 - Led2 - Led3 - Gnd

The Led rating is : 3V - 3,5V 25mA

All Led is On. But when I measure the voltage for between Led pins,
I get this strange result :
Led 1 = +/- 5.4 V
Led 2 = +/- 1,8 V
Led 3 = +/- 1,8 V

Can anyone please tell me why the result is strange ?

Note : The Led is two color (biderectional) Led.
When RED = 3 - 3,5V 25mA
When Green = 4,5 - 5V 35mA
I use RED in my project.

Aina Law
 

Red LEDs have Vf voltage below or close to 2V ..
You should increase the value of resistor from 1Ω to ≈120Ω (25mA) and replace this "5V" LED - most likely it is already "stuffed" ..

Regards,
IanP
 

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