All Questions
Tagged with semiconductors transistors
118
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Diffusion Current for Non-Linear Charge Carrier Configurations
Diffusion current in a MOSFET device can be calculated using Fick's Law per \$J=-qD\frac{d \rho}{dx}\$. It is often taken that the charge carrier configuration (\$\rho\$) across the MOSFET channel is ...
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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
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Bipolar Junction Transistor operating modes
If I use a BJT transistor as a switch, the transistor operates in the saturation or cut-off region, not in the active region.
However, some sources use the formula IC = β·IB. However, this formula is ...
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2
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How do P-type transistors conduct current?
Going through a Introduction to Computing Systems by Yale N. Patt and Sanjay J. Patel and currently reading a chapter on MOS transistors. From what I understand, N-type transistors "close" a ...
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Can I calculate beta by using the quiescent point and a voltage divider?
How can I calculate beta with only the data in the image?
Q is the quiescent point. I've tried with the basics Vcc formulas, but since it doesn't provide any value for Vcc I could not proceed.
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Effect of semiconductor doping on threshold voltage
After reading online, I have modeled this as an relation between the threshold voltage and the doping concentration:
For a N-channel MOSFET on a P-type substrate:
$$
V_{T,N} \propto \sqrt{N_{A}}
$$
...
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3
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387
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What exactly happens at the fundamental level if base voltage is higher than collector voltage in CE transistor?
In the first answer to this question, it is stated that:
This happens even if the base and collector are at the same voltage (!). Basically, one way to model a transistor is as the base-emitter diode,...
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When does the transistor reach the stable status when I add resistor to the emitter
simulate this circuit – Schematic created using CircuitLab
If I add resistor R3, which is an emiter resistor, can it change the value of the base voltage? I've learned that the emmiter voltage ...
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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 ...
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2
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540
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How do the BJT collector and emitter portion compare in terms of size and charge density?
The diagram of a BJT implies that the two p-n junctions are identical. However, I do know that they are not since we cannot connect the transistor the other way around i.e swap emitter and collector, ...
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What does this schematic symbol mean (transistor with two emitters)?
Basically the question is, what it is?
Are those two emitters (meaning that part of semiconductor heavily doped)?
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Is there anywhere I can download BJT Transistor I-V data?
Is there anywhere I can download some current-voltage data for a bipolar junction transistor? (It doesn't matter that much which one.)
To explain further, for a simple BJT circuit we have the ...
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57
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Power dissipation vs. heat dissipation for transistors and diodes
Are these two concept the same or different for semiconductors? Some power MOSFETS have power ratings in the hundreds of watts, and that's way too high for heat loss.
I try to understand 'power ...
- 749
4
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4
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Relation between collector current and Vce voltage in saturation mode
I have confusion regarding how collector current affects the voltage across collector to emitter in NPN transistor (2N4123).
How do I interpret this graph? Can I say when collector current increases ...
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3
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655
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Potential distribution in MOSFET
Let us assume that an NMOSFET has its source, drain and substrate grounded therefore VDS and VSB=0 V . We apply a gate voltage VGS=2 V and I want to know how this potential is distributed as we move ...
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