Questions tagged [nmos]
A n-channel metal-oxide semiconductor (nMOS) transistor has n-type carriers in the channel. A positive voltage on the gate turns inverts the substrate (PWell) creating the channel and turning the device on. The term may also be used to describe logic circuits built around nMOS transistors.
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Using MOSFETs controlled by GPIO pins to switch between two different sources
I need to switch between a constant current source and a programmable power supply to power a lamp.
For both sources, I need to apply 7.6 V to the drain and have the 7.6 V outputted to the lamp. The ...
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Is there anything wrong with using large values for L/W for a PMOS?
Worked on a project recently for a linear circuit design course.
Professor gave us the requirements to build a 5T OTA circuit which must have a gain of 30dB, unity frequency of 200kHz, etc.
Designed ...
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NMOS high side driver: If a resistor is added on the "Vs"/"Vss" input connected to bootstrap capacitor, should external Rgate be reduced?
Following up from a previous question, in the MIC4606 datasheet, it is suggested to protect the "xHS" (called Vs or Vss on most parts I found) pins with a Schottky diode and a resistor, as ...
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Vout NMOS CS amplifier LTspice simulation
I've been trying to create this 2 block cs amplifier for a 5V/V gain. The problem is that my Vout is saturated on both cycles, and I do not know why this is happening.
The transistor used is NMOS ...
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What happens when there is a current source at the drain and gate is GNDed?
In the circuit below, Vin = 0V and there is a 10 uA current source connected to 5V and the drain of the NMOS. Say there is a large resistance R1 at the source and the transistor's W/L is large and Vth ...
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Why does the 2N7000 in CircuitLab not behave the same as on my breadboard?
When simulating the 2N7000 in CircuitLab, I was surprised to see that the current was lower than expected for my circuit (90mA at the drain) when the gate is at 3.3 V. So, I built a quick breadboard ...
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Current running through drain and source on an N channel MOSFET when the Vgs has not been met
I am attempting to create an electromagnetic paper airplane launcher. I am using a hall effect sensor to detect when a sled is passing a solenoid. I am using an Arduino Uno as my microcontroller so ...
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NMOS high-side switch for buck converter
I am studying a buck converter using an NMOS for the high-side switching.
The inverter is supplied by a 3.7 V battery and should power a 0.6 Ω load. The switching is done by a 100 kHz 0-3.3 V PWM ...
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Switching MOSFET reacting much slower than expected on rising edge in simulation vs reality
I have the following schematic. This is a NE555 with voltage controlled by a 12 V voltage reference (TL431) providing a PWM of around 10 kHz at a 90 % duty cycle. The PWM then powers the gate of an ...
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How can I find \$\small V_{GS}\$ in this question?
My attempt:
DC ANALYSIS
Using voltage divider: $$V_{G0}=\frac{200\ \mathrm{k\Omega}}{300\ \mathrm{k\Omega}} \cdot 3\ \mathrm{V} = 2\ \mathrm{V}$$
By KCL $$I_{D0}=I_{D1}=I_{B}=I_{D}=1\ \mathrm{mA}$$
...
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MOSFET differential amplifier
I have two questions about this circuit.
As operating points, Vds=(Vdd-Ir*Rd)-(-Vgs). I do not understand why we put -Vgs.
The second question is, if we take only one output (Vo1) what would Acm (...
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Find a relationship between the input voltage and the current through the diode
So my problem is to, just as the titles states, finding the relationship between the input voltage and the current through the diode for the following circuit.
We have also been given some parameters,...
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NMOS Circuit analysis where the drain and gate are the same
I was trying to solve the following circuit where I have to calculate I_DS and V_DS in the following circuit.
So the first thing I noticed, since that the gate and drain are connected, is that this ...
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How do I find the point where MOSFET changes from triode region to saturation?
I have made a rough plot starting from the cutoff region, where \$\small V_{DS}=V_{DD}\$ until the input voltage crosses the threshold, and then the output voltage begins to drop (approximately ...
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Ultra-fast load switch
I have a question that I am assuming has a very easy answer (hopefully). I am trying to turn on and off the power to a pcb really fast, on the order of 1us. My problem is that my board has some bypass ...
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