I need Ideas/Suggestions

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How do you get 2xVf?
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I found the LED drop voltage of 2Vf using a resistor in series with the 15V power supply. Voltage across led was 2V.


Yes, I noticed this. I used the DMM and it read 2.07V across the diodes just like you say. Or just 2V. 0.66Vf per diode drop. This was on "bench test" not Proteus.


That makes sense. I will put in 120AC to this thing and see if I don't burn the house down.
 
drkidd22 said:
I found the LED drop voltage of 2Vf using a resistor in series with the 15V power supply. Voltage across led was 2V.

...
Click to expand...

Vf for an LED is not 2Vf, it is just Vf for an LED. The LED Vf varies some with current and a lot with color: Technical LED Color Chart.
Vf for diodes also vary with current and type: **broken link removed**

So you measured the Vf of the LED on your bench as 2.0v. Measure the Vf of the optocoupler when you get it. Spec says @10mA it has a typical of 1.17v and a max of 1.4v.

Ken
 
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