All Questions
Tagged with semiconductors diodes
136
questions
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
0
votes
1
answer
64
views
What is a precise definiton of "cut-in" voltage as applied to diodes?
What is the "cut-in" voltage or knee voltage of a diode or transistor?
In a lot of books I read that the cut-in or knee voltage of a diode (or transistor) is when the diode starts conducting ...
- 1
3
votes
2
answers
144
views
Interpreting Diode-Module Datasheet (Voltage Drop)
I'm trying to interpret the datasheet of a Dual-Diode Module, specifically the MF200C12F2N. The internal Circuit Structure is given below:
The Forward Voltage is given as 2.3V without any further ...
- 33
0
votes
1
answer
57
views
Clarification on Diode Recovery Times and Conduction State
I have a diode in my circuit with reverse voltage of 100 V and forward voltage of 2 V.
It experiences a reverse voltage of 100 V and immediately the voltage changes to 10 V in forward direction so it ...
0
votes
2
answers
232
views
Using tunnel diode to cancel out armature resistance
Can we use tunnel diodes to cancel out armature resistance?
A tunnel diode when it is in its negative differential region under DC shifted AC(AC with some DC offset) and if the Vp-p of the AC is very ...
0
votes
3
answers
188
views
Semiconductor theory
Why is there no resistor in the circuit when analyzing hole and electron currents according to semiconductor theory?
- 31
1
vote
1
answer
552
views
Understanding the formula of the saturation current in a PN-junction diode
According to Wikipedia, the saturation current in a diode is given by the following formula:
$$I_S = qAn_i^2\left(\frac{1}{N_D}\sqrt{\frac{D_p}{\tau_p}} + \frac{1}{N_A}\sqrt{\frac{D_n}{\tau_n}}\right)$...
- 121
0
votes
1
answer
104
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Contribution of hole diffusion current and electron diffusion current in a pn junction
I have recently got to learn that the hole diffusion current and electron diffusion current both point towards the N side in a PN junction? And the diffusion current is hence towards the N side.
And ...
- 23
0
votes
1
answer
50
views
Drift Current in PN Junction and Barrier Voltage
I am reading this book, but the idea presented by it is very unclear.
It quotes:
However, I am not entirely convinced with the reason it provides here, like why are the minority carriers that reach ...
- 23
3
votes
1
answer
98
views
Why is diffusion current due to p side in a diode inversely proportional to doping concentration of p side in the case of forward bias?
In a diode at equilibrium, there are Pn holes on the n side of the junction. These are maintained by the dynamic equilibrium of diffusion due to holes = drift due to holes. When a forward bias is ...
0
votes
1
answer
145
views
Why doesn't a diode pass current when reverse biased?
If one tacks a P-type semiconductor to an N-type semiconductor, a P-N junction forms in which electrons diffuse from the N-type to the P-type causing a diffusion current. Some time passes, and an ...
- 339
0
votes
1
answer
402
views
Fermi levels in PN-junction under forward bias are not constant throughout each side
This is, in a way, a follow-up to this question.
I see the following band diagram for a forward biased diode everywhere:
In the above picture, I marked a point with potential zero (where battery is ...
- 163
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
0
votes
1
answer
71
views
Diodes in parallel reduce current compared to single measurement
I have a photonics integrated circuit with two quantum well diodes. (exact description below)
If I measure the IV curve for each individual diode I get pretty much the same curve for both. but if I ...
0
votes
1
answer
54
views
What does the interface between lead(s) and the silicon chip look like inside a semiconductor package?
For a leaded semiconductor, like a diode or a transistor, one of the leads is usually the same piece of metal as the copper pad/heat spreader on the back, which is also shorted to one of the junctions ...
- 749