Why fet is called a voltage-controlled device, Electrical Engineering

Assignment Help:

Q. Why FET is called a voltage-controlled device? Why its input resistance is high?

In the case of a FET the output current ID is a function of the voltage VGS applied to the input circuit. Hence FET is known as a voltage controlled device. The equation that governs the working of a FET is called Shockley's equation given by,

ID = IDSS[1 - (VGS/VP) 2

where, ID is the drain current

IDSS is the maximum saturation current

VGS is the voltage applied between gate and source

VP is the pinch-off voltage

A FET requires virtually no input current and hence IG is always made zero. This gives an extremely high input resistance to FET. The range of its input impedance is at a level of 1 to several 100MWs.


Related Discussions:- Why fet is called a voltage-controlled device

Switching characteristics, Switching Characteristics The switching  cha...

Switching Characteristics The switching  characteristic  of an IGBT  during  turn on and turn off time all  shown  in the sum of delay time  and rise time gives  the total  tur

Analog Filters, Each of the following functions is abs(H(jw))^2 of a certai...

Each of the following functions is abs(H(jw))^2 of a certain network function H(s). Obtain all the possible H(s) for each given abs(H(jw))^2. [(w^4)+25]/[(w^4)+(12w^2)+49]

Compute the eddy-current loss in the core, Q. The flux in a magnetic core i...

Q. The flux in a magnetic core is alternating sinusoidally at a frequency of 500 Hz. The maximum flux density is 1 T. The eddy-current loss then amounts to 15W. Compute the eddy-cu

Calculate the actual frequency response, Using the LM741operational amplifi...

Using the LM741operational amplifier build a current amplifier with the voltage gain of  |A V | = 300 v/v ± = 20% . Measure all necessary parameters of the amplifier (as per delive

Calculate the power factor of the motor, A 3 phase 400 volt(line to line) w...

A 3 phase 400 volt(line to line) wye connected synchronous motor has Xs= 1 ohm per phase and a negligible armature resistance. The field current is so adjusted that the internal(in

Calculate the speed of motor when armature current is 25 a, Q. The magnetiz...

Q. The magnetization curve taken at 1000 r/min on a 200-V dc series motor has the following data: Field current, A: 5 10 15 20 25 30 Voltage, A: 80 160 202 222 236 244 Th

Rst restart instructions , RST Restart Instructions Restart instructio...

RST Restart Instructions Restart instructions  are one byte call instructions. Called location for each restart instruction is  predefined on page 0 ( read only memory). They

Flex routing , Flex Routing : You can see that your labour will have bee...

Flex Routing : You can see that your labour will have been in vain unless you take steps to ensure that flexes are routed safely and well clear of possible sources of danger.

Storage oscilloscope, Aim To build a simple storage oscilloscope usi...

Aim To build a simple storage oscilloscope using the PIC trainer To report on the program's design and operation Equipment PIC Trainer and PICkit3 in-circui

Write a short note on heat sink, Q. Write a short note on heat sink For...

Q. Write a short note on heat sink For transistors handling small signals ,the power dissipated at the collector is small.Such transistors have little chances of thermal runawa

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd