Questions tagged [fet]
Field Effect Transistor, a transistor in which most current is carried along a channel whose effective resistance can be controlled by a transverse electric field. Commonly used types of FETs include the Metal Oxide Semiconductor FET (MOSFET), and less common in recent designs, the Junction Gate FET (JFET or JuGFET).
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How would one calculate the transconductance of the FETs in this circuit?
I was given formulas to find the transconductance (gm) of the FETs using IDSS, VP and VGS, however, none of the ways I tried them leads to the correct answer (given as 2,55mS).
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Why do some JFETs oscillate and others don't?
Below is a simple JFET Clapp Oscillator, which works quite well. It starts oscillating at around 40us and gets into clean, stable oscillation by 100us:
When I replace the J309 JFET with a more ...
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MOSFET feedback mechanism
I made an simple feedback circuit. R2 and R3 is voltage divider there so I'm setting them sufficiently big values. But in this setup, it works with 2N7002 and not IRFZ44N (gain is way less then I set ...
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DC Electronics Load Part Capacity
Sure, here's your question translated into English:
I'm working on developing a DC electronics load that I intend to discharge at up to 30V and 60A. For this, I'm using the FBSOA MOSFET IXTN200N10L2, ...
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What is the difference between using op amp and transistor for small signal amp? [closed]
I have a question.
As you know, not only the transistor can be used for switching level or amplifying small signal (single or multiple stage design), but also op-amp can be used in same purpose. So ...
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is Vov of a nMos always VGS - Vt?
Looking at this graph from Analog Circuit Design Discrete and Integrated by Sergio Franco, is it always true that Vov = VGS - Vt? or is this only true at pinchoff point?
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Using an N-channel FET as a switch
I want to use an N-channel FET as a pass gate SPST switch to let an FTDI reset signal through to to my microcontroller or not, based on an independent signal.
simulate this circuit – Schematic ...
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LED indication for driven n-FET inputs
Given that I'm using a microcontroller (e.g. an ATtiny85) output pin to drive the gate of an n-channel FET (e.g. NTMD6N02R2G) acting in the role of an SPST switch, is there any issue with either of ...
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Small signal equivalent circuit of multistage amplifier
I've been trying to draw the small signal equivalent circuit of this circuit and derive the expression for voltage.
Using the equivalent circuit I drew, I derived the voltage gain expression but I got ...
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Do FETs need to be biased?
From my knowledge, BJTs need to be biased to control its linearity and gain, usually with resistors on the base and collector.
Suppose I want a FET in saturation acting as a high-side switch.
Do FETs ...
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AC analysis of a Bias Tee
I am designing a bias tee here and wondered whether it actually works or not? Hence I conducted an AC analysis instead of S-parameters (after verifying that s parameters are okay). The bias tee has ...
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Where is the body terminal of a FinFET connected usually in digital circuits and in analog circuits?
What is the usual practice in industry regarding the body terminal of a FinFET?
Is it connected to the source to eliminate body effect?
Or is it connected either to the ground(nfet) or the supply(pfet)...
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FET turn-on time in DC-DC converter
I am selecting a GaN FET for a buck-boost DC-DC converter application. The Vgs of the part I'm looking at combined with the gate charge and gate resistance lets me switch the FET on in about 5.3 ns. ...
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Difference between Kelvin and Celsius in dynamic thermal behavior of MOSFETs
I am trying to understand the temperature behavior at the junction level and this Application Note "AN_201712_PL11_001" from Infineon describes the process.
The problem is that I have a hard ...
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Difference between IGBT and FET+BJT
What are the practical differences between a true IGBT and a combination of FET and BJT, apart from a more efficient production and packaging? Can I obtain a device of comparable qualities to IGBT if ...
