Transfer Characteristics of Real and Ideal Diodes (and more sources)

[eximius]

I'm looking for information regarding the "Transfer Characteristics of Real and Ideal Diodes". I've tried google and the section on this site for learning material, but I've failed to find a site that displays both transfer characteristics and explains them. I was hoping that someone would have a site that discussed both or supply me with the information.

I'm also looking for a general site that would help me with UK university level electronic engineering work. Things such as diode applications, transfer characteristics, diode modelling, amplifiers and the maths associated with digital electronics such as boolean expressions, logic gates, truth tables and Karnaugh maps.

Any and all help would be greatly appreciated. Thanks.

[berkeman]

I'm looking for information regarding the "Transfer Characteristics of Real and Ideal Diodes". I've tried google and the section on this site for learning material, but I've failed to find a site that displays both transfer characteristics and explains them. I was hoping that someone would have a site that discussed both or supply me with the information.

I'm also looking for a general site that would help me with UK university level electronic engineering work. Things such as diode applications, transfer characteristics, diode modelling, amplifiers and the maths associated with digital electronics such as boolean expressions, logic gates, truth tables and Karnaugh maps.

Any and all help would be greatly appreciated. Thanks.

Welcome to the PF.

Wikipedia's intro to diodes is pretty good:

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

For ideal diodes, they would not have any reverse breakdown, and no reverse leakage current Is. They would also have a right-angle break at the forward voltage Vf, going from no conduction to full conduction (zero resistance).

[vk6kro]

Ideally, they wouldn't even have a forward voltage drop.

Any forward voltage on them would produce full conduction.

http://dl.dropbox.com/u/4222062/real%20vs%20ideal%20diode.PNG

[eximius]

Thanks guys. Massive help :)

Rather than starting a new thread. Could someone help me with the equation for the voltage ripple in a half wave rectifier? I have the full wave rectifier equation. But I can't find the half wave one anywhere on the internet. People only seem to be interested in the ripple factor.

Thanks again.

[vk6kro]

Ripple voltage is covered in this link:

http://en.wikipedia.org/wiki/Ripple_(electrical)

Click on it, then see under "time domain ripple".

Note that C is in Farads.

[eximius]

So half-wave ripple = T/RlC

as r = dVl/Vm
and dVl = TVm/RlC

And full-wave ripple = T/2RlC

But I'm still uncertain about the Vm. Is it simply the peak voltage? As in points 1 on the sine wave?

[eximius]

I've got an example that seems to work with r = T/RlC

With a half-wave rectifier, calculate the capacitance needed for a ripple of 10% given an applied signal frequency of 50Hz and a load resistance of 500ohms.

r = T/RlC r = 10% = 0.01, Rl = 500ohms, T=1/f=1/50

.:.

0.01 = (1/50)/(500*C)
5*C = 1/50
C = 1/250 F
C = 4x10-3 F
C = 4mF

Am I correct in thinking this?

[eximius]

Bump, sorry.