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What is the meaning of voltage control device and current control device y they call like this?
In vcd, input voltage controls the output current.e.g.jfet In ccd , input current controls the output current. e.g. bjt
Which semiconductor power device is not a current triggered device?
Power FET
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.
Why input current of USis less than Output current?
Why input current of USis less than Output current?
Why you need operational transconductance amplifier?
Usually output of an amplifier is a voltage ,...but in case of Operational Transconductance Amplifier ,Iout (current ) is the output. This feature, makes it useful for Electronic control of amplifier gain .
Why is a cascode current mirror better than a simple MOSFET current mirror?
In simple MOSFET current mirror, the load current does not follow a linear relationship with reference current (ie for short channel MOSFET's multiplying factor due to channel length modulation cannot be neglected). But by cascoding the output resistance can be increased and since output resistance follows an inverse relationship with lambda (channel-length modulation parameter), the multiplying factor due to channel length modulation reduces to one and a linear relationship is obtained between reference and load current.
What is the meaning of voltage control device and current control device y they call like this?
In vcd, input voltage controls the output current.e.g.jfet In ccd , input current controls the output current. e.g. bjt
Why is CMOS better than single MOSFETs?
CMOS is better than single MOSFETs because the complementary MOSFETs in CMOS always have one off and the other on, reducing the idle current to only leakage current and the output voltage exactly equal that of either the power or ground as there is no voltage drop across the MOSFET that is on. With just one MOSFET the device draws current anytime it is in the on state, even if idle.
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.
Can we replace a thyristor by a mosfet?
No because a mosfet does not work the same as a thyristor. In a thyristor the current flows even when the gate pulse is removed, until the current stops. That is not the case for a FET.
What is the difference between mosfet and photo diode?
the current in mosfet is controlled by electric field where as in poto diode is controlled by intensity of light
Why mosfet is not removed from the circuit when the supply is on?
it can exchange the current is much larger and has Avery low resistance when it is turned on.the mosfet is not removed from the circuit when the supply is on because it flow the high current.
Advantages and disadvantages of depletion MOSFET?
Since the logic operations of depletion MOSFET is the opposite to the enhancement MOSFET, the depletion MOSFET produces positive logic circuits, such as, buffer, AND, and OR. The most significant advantage of the positive logic circuits is that it can produce positive feedback easily so that a single depletion MOSFET can become a memory cell. In contrast, you will need at least two enhancement MOSFET transistor to produce the positive feedback to build a memory cell. The other advantages of depletion MOSFET are that it is free from sub-threshold leakage current and gate-oxide leakage current. Since there is always a potential difference of Vdd between the gate terminal and channel for an enhancement MOSFET to cause the gate-oxide leakage current, the gate oxide leakage current is unavoidable when the transistor shrinks in size and oxide layer becomes thinner. The depletion MOSFET does not have this problem because there is no potential difference between the gate and channel. As a enhancement MOSFET shrinking in size, there is no way to stop the subthreshold leakage current diffused across from source to drain because the drain and source terminals are closer physically. This is not a problem for depletion MOSFET because a pinched channel will stop the diffusion current completely. The depletion MOSFET is the ideal, perfect transistor. The only disadvantage of depletion MOSFET is its inability to produce negative logic operations.
If current flow in both direction in mosfet?
Do you mean "can current flow in both directions"? In theory, yes.
Which semiconductor power device is not a current triggered device?
Power FET
What is ac chopper?
AC chopper is also called AC voltage controller. In AC voltage controller, we use 2 thyristors as switching element. In AC chopper we use MOSFET or IGBT as switching element with diodes in bridge rectifier for bidirectional flow of current. This use of mosfet switch has the following advantages over thyristor: * no separate firing circuit are needed for Mosfet ( it can be driven directly by interfacing it with MC) whereas firing circuits are needed for SCR. *when the line current drops to zero SCR turns off due to natural commutation( when it reaches 172 deg) ; mosfet- user control - we can turn on and off as per our requirement. * snubber circuit is needed for thyristor phase control method. By using mosfet in diode rectifier provides internal snubber
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.
