# How Diodes work?

1. Jul 14, 2006

### esmeco

I do not know much about diodes and I wanted to know if someone could explain me how do semi conductor diodes work and how do we determine in a circuit(dc and ac) the input voltage and the output voltage...

2. Jul 14, 2006

### SGT

3. Jul 14, 2006

### Staff: Mentor

The wikipedia entry for diodes is pretty good:

http://en.wikipedia.org/wiki/Diode

It's important to have the V-I plot of a diode in your head when you are working on problems that include diodes. You should learn the diode equation

$$I = I_s (e^{\frac{qV}{kT}} -1)$$

and learn about the reverse breakdown characteristic (used in Zener diodes, for example).

4. Jul 14, 2006

### wolram

Was there a vacuum tube version of a zener diode?

5. Jul 14, 2006

### Staff: Mentor

Interesting question. So I googled +"vacuum tube" +"zener diode" and got some hits. Go to this one for example:

http://members.aol.com/sbench101/ [Broken]

and do a text search on Zener. That will get you down the page to one way to do it with tubes.

Last edited by a moderator: May 2, 2017
6. Jul 14, 2006

### wolram

Great site, Thanks berkeman.

Last edited by a moderator: May 2, 2017