Questions tagged [linear-region]
The linear-region tag has no usage guidance.
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Is the Rds(on) of a MOSFET typically specified at the boundary of the saturation and triode regions?
Datasheets specify the Rds(on) of a MOSFET at some specific gate-source voltage, e.g. 100mΩ @ Vgs=4V. Up until now, I assumed that the test gate-source voltage was essentially arbitrary and chosen ...
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Linearity in Differential Amplifier
Trying to understand what is the maximum and minimum for the input signal of a differential pair by solving this example below.
My solution: To let the circuit operate as a differential pair, it must ...
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Why aren't these instrumentation amps working for linearly driving a generic MOSFET?
If you've read my previous posts, I would say now that I've pretty much given up on the idea of parallelizing op-amps. I've stumbled onto instrumentation op-amps and decided they were good enough for ...
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Operating of FET in linear region
I have some data and would need some help to design a schematic. My target is to deal with the inrush current. I have a supply voltage range of 25-42V. A capacitive load of 1500uf. So I would like to ...
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MOSFET in linear region
Can we work with a MOSFET only in the linear region? I want to use it as variable resistor so it can provide a fixed amount of current. The MOSFET SOA should not be violated.
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Why is the collector region doped?
As long as within the active region the collector-emitter junction is reverse biased, is there a purpose for which the collector must be doped? Moreover, not only that it is doped, but it is ...
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MOSFET terminology seems to vary in every article I read
For someone trying to learn about FETs, it seems there is no consistency in terminology (unless I am reading things wrong.)
I am trying to understand the FET as a switch (for power applications.) It ...
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FET DC operation in the ohmic region if the SOA curve doesn't have a DC line?
From my understanding, the SOA lists the drain current for a given VDS in the ohmic and saturation regions where the FET can function without damage.
I read a thread that says FET SOA graphs with ...
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MOSFET operating point in linear mode
I have this question, where the drain-source current and its bias gate voltage of a MOSFET is known where source is connected to ground.
I find its drain current is less than saturation current by a ...
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Transistor - Saturation and Active Regions
I am using this BC817-40 transistor as a switch.
In the above image, we can see that inorder to operate my transistor in the saturation region, I need to make sure my Ic/Ib ratio is less than 40.
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MOSFET regions of operation
Let's say I have a MOSFET already operating in saturation such that
Vds > Vgs - Vth. Can I make it to operate in triode or linear region by simply varying the drain voltage such that now Vds < (...
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Current Mirror Circuit
Below is a sample current mirror circuit.
I understand that If the transistor Q1 is connected in a diode connected BJT configuration and the Transistor Q1 and Q2 have identical transistor parameters,
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CCD sensor: Digital Counts vs Exposure plot vs Dark Digital Counts
First, my question concerns an individual pixel/sensor from a CCD array of a digital camera.
From my understanding, the Digital Counts is linear with Exposure time. However, this line will be ...
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How to conclude region of operation for a series combination of MOSFET
I understand that M1 is on and for M2 to be on the intermediate voltage(drain on M1 and source of M2) should be less than 1.5V. Also if M2 is ON then M2 is in saturation since Vds>(Vgs-Vt) for M2. Now ...
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Finding MOSFETs with greatest linear region
I want to make a cheap variable gain amplifier using an op-amp, using a MOSFET as the variable resistance. The circuit is for an audio application at line (signal) levels (ballpark of 1v peak to peak)....