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So I am looking at my spec sheets, I am running most of my boards on 5V (Arduino)
There are however 5 LEDs that say can have a maximum FV of 1.5V, so I am pretty sure they will fry if I run the 5V through them, there are also 5 Photodiodes that have a 1.3 maximum FV, so they will fry as well.
What I was thinking is connecting them all to my VCC, but to add a resistor right before the actual component, which would create a voltage drop. (I am not sure if this would work though)
So I am thinking of doing this:
http://img12.imageshack.us/img12/1894/una0.png
Now I am not sure if this will work, I tried setting that up in MultiSim, but it didnt show any voltage drop across the resistor, it kept saying the Voltage going to the PD and LED were still 5V which I really want to avoid.
I calculated this using the following:
Knowing the current and voltage for the PD
10 mA, and 5V, I want a drop of 3.7V, so V=iR
so that gives a resistor of 370 Ohms for the Photodiode, and using the same logic a Resistor of 175 Ohms for the LED.
Will this work? or will my components still fry?
Thank you for all your help
There are however 5 LEDs that say can have a maximum FV of 1.5V, so I am pretty sure they will fry if I run the 5V through them, there are also 5 Photodiodes that have a 1.3 maximum FV, so they will fry as well.
What I was thinking is connecting them all to my VCC, but to add a resistor right before the actual component, which would create a voltage drop. (I am not sure if this would work though)
So I am thinking of doing this:
http://img12.imageshack.us/img12/1894/una0.png
Now I am not sure if this will work, I tried setting that up in MultiSim, but it didnt show any voltage drop across the resistor, it kept saying the Voltage going to the PD and LED were still 5V which I really want to avoid.
I calculated this using the following:
Knowing the current and voltage for the PD
10 mA, and 5V, I want a drop of 3.7V, so V=iR
so that gives a resistor of 370 Ohms for the Photodiode, and using the same logic a Resistor of 175 Ohms for the LED.
Will this work? or will my components still fry?
Thank you for all your help
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