Have 3,3V need 15V

[Martaine2005]

I don’t know anything about Arduino yet although I have a few but never tried them.
Many users on here do use them and they can answer your questions.
However, I do believe you can use 0’.


Martin

 

[Stuefi]

Oh my goodness!! Last time I tried this it didn't work. Thank you all for your help!! But why does the diode reduce the voltage by about 0.7V? I thought the diode just lets the power in one direction through. Is there a remaining resistance?

 

[John Canon]

The 0.7 voltage drop is an inherent characteristic of the P-N junction. It is always 0.7 volts regardless of the current flow. Imagine a one-way water valve with a spring loaded flapper. The spring pressure in the valve is similar to the voltage drop in all diodes. Now I am waiting for someone to tell me the ways I am wrong. haha.

 

[Martaine2005]

Yeah, that’s a difficult question to answer unless you understand physics. Which I don’t.
I suggest you read up on ‘depletion region’ and ‘P-N junctions’.
It’ll give you a better understanding.
In any case, you don’t need ‘the’ diode.
LEDs are diodes (light emitting diodes), so won’t work if connected in reverse bias and they too have a forward voltage drop. Which put simply is the voltage required to turn them on. (Although technically they’re current driven devices). Have a good read and enjoy.


Martin