All Questions
Tagged with semiconductors diodes
136
questions
45
votes
8
answers
11k
views
Why isn't there a potential difference across a disconnected diode?
I know this question sounds silly, as if there was a potential difference a current would be created when the terminals are connected together and this would mean energy has come from somewhere.
The ...
- 1,655
38
votes
2
answers
3k
views
How does current get into a diode?
I think I understand more or less how an ordinary semiconductor diode works: Crystal doped differently in different regions, carrier depletion where they meet, bla bla bla.
However, actual diodes ...
21
votes
3
answers
26k
views
How should I understand the intrinsic body diode inside a MOSFET?
I know there is an intrinsic body diode inside all the MOSFETs, but I'm confused about the reason why it's there. I've searched the articles but can't find a good explanation for it. Can anyone use ...
- 681
16
votes
5
answers
4k
views
Resistance depending on voltage - the chicken and the egg?
If I understand correctly:
The resistance of some circuit components (like diodes) depends on the voltage across them.
When two components are connected in series: \$\frac{V1}{V2} = \frac{R1}{R2}\$
...
- 181
14
votes
3
answers
2k
views
Perpetual machine from a PN-junction diode
Consider a PN junction diode
Now, this system will naturally form a depletion region due to diffusion and will convert into this:
Now, I wish to connect the ends of this diode with a conducting wire ...
- 259
12
votes
4
answers
18k
views
Why can current flow through the reverse biased base-collector junction (N-P junction) in a BJT with a forward biased base-emitter junction?
If the base-emitter junction of a BJT is forward biased, then current can flow through the reverse biased base-collector junction (N-P junction). This disagrees with my understanding of the PN ...
- 1,655
12
votes
1
answer
2k
views
Why do power diodes have a p+ n- n+ construction and why not p+ p- n+?
I've been learning about power diodes and how they differ from low power diodes with the addition of a lightly doped n-type layer.
This n-type layer improves the breakdown voltage rating of the ...
9
votes
2
answers
12k
views
minority carrier life time? Why is it important for devices' switching speed. Why not majority carriers?
I am trying to get my head around why would a silicon engineer care about the minority life time carrier and how does the minority carrier affect the switching speed of PN junction. Why is it so much ...
- 1,652
8
votes
7
answers
6k
views
Resistance of a semiconductor diode
When we calculate the dynamic resistance \$r=(\frac{dv}{dI})\$, for any n-p junction, how is it different from the normal resistance \$R=\frac VI\$? Does the equation for the voltage drop (The fermi ...
- 169
7
votes
5
answers
2k
views
Why can't a P-N junction diode be used as a voltage regulator or reference in forward bias?
Usually, a Zener or avalanche breakdown region for a suitably doped P-N junction is used for voltage regulation as a substantial variation in the current (due to minority carriers) requires a ...
- 189
7
votes
5
answers
3k
views
Series connection of diode and resistor. Why is there a constant voltage across the diode?
So I know that a diode can be described using the Shockley equation and after a certain voltage, the diode current begins to increase rapidly. The nominal 0.7 volts. I also know that this voltage ...
- 81
7
votes
2
answers
72k
views
E-K diagram in case of semiconductors
I am currently studying solid state electronic devices and want to build my concept in this subject. Can anyone explain to me what is E-k Diagram and what is its significance?
6
votes
2
answers
2k
views
Current flow through diode
What if we decrease/increase the resistance 3kohm to a higher/lower value? Can someone explain this behaviour to me in a very simple way? Will the current then flow through the silicon diode?
- 480
6
votes
1
answer
3k
views
What is exactly modeled by 'transit time' in SPICE diode model?
I'm trying to find a precise definition for the transit time parameter in SPICE diode model. What I think is the official documentation for standrad Berkeley SPICE diode model says the following
...
- 577
5
votes
3
answers
3k
views
Why does the forward voltage drop in a diode vary slightly when there is a change in the diode current?
I was going through Basic Electronics and Circuits by David. A.Bell and there it mentioned that the forward voltage drop in a diode varies slightly with a change in forward current - but there is no ...
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