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This refers to the voltage Vds that counteracts the opening of the n-channel (NMOS), at the drain end. Since the width of the channel is a function of Vgs - Vtn, the mosfet saturates (pinches off) when Vds is greater or equal than/to Vgs - Vtn.
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What are the differences betweeen e-mosfet and d-mosfet?
An e-mosfet is and "enhancement" mosfet. A d-mosfet is a "depletion" mosfet. These essentially show what mode the mosfet operates in when a voltage is applied to the gate. . An enhancement mode mosfet is normally non-conducting but conducts when the channel is enhanced by applying a voltage to the gate and pulling carriers into the channel. A depletion mode mosfet normally conducts but becomes more and more non-conducting as carriers are depleted or pulled out of the channel by applying a voltage. The polarity of the voltage depends on whether it is an N channel or P channel. P channel uses positively doped silicon while N channel uses negatively doped silicon. N channel fets are used wherever possible because N material conducts better than P material. There are basically two types of fet, the jfet and the mosfet. The jfet uses a single junction to control the channel hence draws some current. Bipolar transistors use two junctions. In the mosfet (Metal Oxide Semiconducting Field Effect Transistor) there is no such junction hence draw so little current for control purposes it can be regarded as zero. The gate is isolated from the channel by a very thin layer of metal oxide (usually chromium dioxide). An enhacement mode mosfet can be turned on by applying a voltage then removing the wire to the gate. The channel will then remain conducting for some time.
How do you keep mosfet from overheating i use only mosfet and control it using variable resistor it works but it gets overheated and brokedown.My battery operated scooter is 24v dc 72 amp.thank you.?
Use a mosfet driver instead of a simple resistor. Using a resistor to control the mosfet is a bad idea anyways because you will have terrible control (mosfets are voltage controlled. Take a look at the response curve for your mosfet). If your mosfet is fully on, its ratings may be too low for continuous operation or the power dissipation is too low for the transition between off an on an that is killing your mosfet.
What is normally-On MOSFET?
Depletion mode MOSFET is normally on device --vlsijp
What did mosfet do?
A: A silicon bar basically can pass current but if a voltage of the right potential is applied it constrict the flow. basically that is it. Further Explanation: A MOSFET (metal oxide semiconductor field effect transistor) is composed of three doped regions - two N type and one P type or vice versa. When a voltage is applied to the gate (the single P type in NPN, or N type in PNP), this causes a path to be created in the gate material. If the gate material is P type, a positive voltage will cause electrons to concentrate near the gate terminal. This concentration of electrons acts as a wire between the two N type materials. As more voltage is applied, the voltage gradient across the P type material will increase (to a point), resulting in a larger virtual "wire" of electrons. A PNP type transistor operates in a similar fashion.
What is subthreshold slope for mosfet?
what is subthreshold swing
Power MOSFET is voltage controlled or frequency controlled device?
A Power MOSFET is a voltage controlled device http://www.profesores.frc.utn.edu.ar/industrial/sistemasinteligentes/UT1/Understandig%20Pwr%20Mosfets.PDF
What is the function of enhancement mosfet?
An enhancement MOSFET doesn't conduct current across the drain to source unless a voltage is applied to the gate. When sufficient voltage is applied to the gate of the transistor, currents flows from drain to source. A MOSFET acts as a switch or amplifier in a circuit.
Main factor which differ De mosfet from an e only mosfet?
An e only(enhancement) ÊMOSFET is off at zero gate-source voltage. Meanwhile, a de (depletion enhancement)ÊMOSFET is on at zero gate-source voltage.
The value of gate voltage for the operation of enhancement of only N channel MOSFET has to be?
high...
Can depletion mosfet act as enhancement mosfet?
It depends. A depletion MOSFET can be used as an ehancemnet MOSFET when it is operated as an analog amplifier. However, a depletion MOSFET can't replace an enhancement MOSFET when it is operated as a digital switch. When a depletion MOSFET is used as a digital switch, since the junction between source terminal and substrate must be reverse biased, the voltage of the source terminal of an N typde transistor must be tied to Vdd, and it is completely opposite to an enhancement MOSFET. When a depletion MOSFET is used as an analog amplifer, the source terminal and the substrate are both at the same potential, just like an enhancement MOSFET.
What happens if a negative voltage is applied to the gate of the n and p channel MOSFET?
It depends on: 1. technology, whether it's a JFET, enhancement-mode IGFET/MOSFET or depletion-mode IGFET/MOSFET, and 2. polarity, whether it's an N type or P type. More info needed for this one.
What are the differences betweeen e-mosfet and d-mosfet?
An e-mosfet is and "enhancement" mosfet. A d-mosfet is a "depletion" mosfet. These essentially show what mode the mosfet operates in when a voltage is applied to the gate. . An enhancement mode mosfet is normally non-conducting but conducts when the channel is enhanced by applying a voltage to the gate and pulling carriers into the channel. A depletion mode mosfet normally conducts but becomes more and more non-conducting as carriers are depleted or pulled out of the channel by applying a voltage. The polarity of the voltage depends on whether it is an N channel or P channel. P channel uses positively doped silicon while N channel uses negatively doped silicon. N channel fets are used wherever possible because N material conducts better than P material. There are basically two types of fet, the jfet and the mosfet. The jfet uses a single junction to control the channel hence draws some current. Bipolar transistors use two junctions. In the mosfet (Metal Oxide Semiconducting Field Effect Transistor) there is no such junction hence draw so little current for control purposes it can be regarded as zero. The gate is isolated from the channel by a very thin layer of metal oxide (usually chromium dioxide). An enhacement mode mosfet can be turned on by applying a voltage then removing the wire to the gate. The channel will then remain conducting for some time.
What are depletion and enhancement mosfet?
A depletion MOSFET is a MOSFET that is normally on. It outputs maximum current when the gate-source voltage is 0V. As the gate-source voltage increases, the drain-source channel becomes more resistive and the current decreases. An enhancement MOSFET has the opposite behavior. It is normally off. It outputs no current when the gate-source voltage is 0V. As the gate-source voltage increases, the drain-source channel becomes less resistive and the current increases.
The value of gate voltage for the operation of enhancement of only N channel MOSFET has to be high positive?
yes.
What the threshold voltage depends on?
It basically depends on the biasing of a transistor. In case of a MOSFET, it depends on the substrate biasing.
How do you keep mosfet from overheating i use only mosfet and control it using variable resistor it works but it gets overheated and brokedown.My battery operated scooter is 24v dc 72 amp.thank you.?
Use a mosfet driver instead of a simple resistor. Using a resistor to control the mosfet is a bad idea anyways because you will have terrible control (mosfets are voltage controlled. Take a look at the response curve for your mosfet). If your mosfet is fully on, its ratings may be too low for continuous operation or the power dissipation is too low for the transition between off an on an that is killing your mosfet.
Why self bias is not used in enhansement type MOSFET?
Because for creating channal we need voltage at gate if there is no voltage at ate then VGS=0 this mean no amplificatiion can be done.
