All Questions
Tagged with semiconductors transistors
118
questions
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2
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534
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Intuitive way to think of transistor saturation current?
I am having a hard time understanding what saturation current (denoted Is in my textbook) actually means for a transistor.
For a diode, it makes perfect sense, it's the approximate maximum reverse ...
- 199
0
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2
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203
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Why do NPN/PNP transistors need to use doped semiconductors for the 'N' region?
By my understanding, as long as the P layers are properly doped (to have fewer free electrons), the electrons could not flow between collector and emitter until the P is given a satisfactory level of ...
0
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1
answer
202
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the transconductance of cascade MOSFET IF channel length modulation is NOT ZERO
What would the derivation of the cascode MOSFET transconductance in small signal analysis IF THE CHANNEL LENGTH MODULATION IS NOT ZERO, as most examples for the cascode mosfet transconductance say in ...
0
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1
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108
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Semiconductor common emitter configuration
Please could anybody explain the CE configuration, the graphs of \$I_b\$ vs. \$V_{be}\$ and \$I_c\$ vs. \$V_{ce}\$. I can't understand which current remains fixed and how can one regulate \$V_{ce}\$ ...
- 103
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Is it misleading to say "holes in semiconductors jump to the other side"? [duplicate]
I'm getting a little confused with the convention of saying that "holes in a semiconductor will move from p-side to n-side and electrons will move the opposite way". I have no trouble with the concept ...
- 530
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5
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Why reverse connected MOSFET start to turn on at Vgs<Vth?
The circuit shown below is implemented using two AO3400 N-MOSFETs.
AO4300 datasheet here.
The right-hand MOSFET is connected with normal polarity (Vds is positive),
while the left-hand MOSFET is ...
- 93
1
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1
answer
181
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BJT transistor working and construction
Why is electron concentration zero at collector side of the base in BJT transistor? And if electron concentration decreases with distance and becomes zero at the end base region how can it produce ...
- 111
6
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163
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MOSFET switching on
I have a doubt. Consider an N-MOSFET: which is the voltage that can switch on it? The voltage between Gate and? Sometimes I read "between Gate and Bulk", sometimes "between Gate and Source", sometimes ...
- 3,550
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4
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Why does the base-emitter voltage in NPN transistor become constant?
The setup above shows the experiment that I have been working with. During the experiment, the current \$i_c\$ and the voltage \$V_{be}\$ were measured for increasing \$V_{in}\$. At some point, the ...
- 13
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1
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Question about transitor NPN [ALFA;Strange configuration;Exit characteristic]
first of all thanks for read and for your time, I have a few questions about transistor:
1)
I can't understand why my book say:
Ic=Icb0+alfa*Ie
and not ...
- 13
1
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3
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976
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BJT Active mode - How does it work
I am finding it difficult to understand how exactly this works and would appreciate any help.
From my understanding:
The emitter base junction has to be in forward bias meaning that Vb is more ...
- 451
1
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2
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285
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Cause of triode mode in MOSFET
My reference text introduces the MOFSET as follows:
The text says the induced channel has uniform width as long as \$v_{DS}\$ is small, because in that case \$v_{GD} = v_{GS} - v_{DS} \approx v_{GS}\$...
- 137
1
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1
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Why is Ic constant in the plot of Vce vs Ic in a common emitter NPN transistor (in active region)?
In this plot, when \$V_{ce}\$ increases in the active region, shouldn't \$I_c\$ also increase as more electrons are getting diffused into the collector?
Then, why is it that for a large range of \$V_{...
2
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0
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116
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How does a MOSFET conduct in saturation region?
It is a simple question but I could not find a straightforward answer.
When a MOSFET enters saturation region, the channel length starts to decrease, and the channel width is the smallest near the ...
-2
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2
answers
612
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Is the resistance between collector and emitter is lower that of the path between collector and base? [closed]
If no, pls tell me why. And if yes, my question is how can the path C-B-E be have lower resistance than that of B-E? Shouldn't the resistances of BE and CB add up cause they're in series?
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