What is advantage and disadvantage of FET?

➨It has relatively lower gain-bandwidth product compare to BJT. ➨Transconductance is low and hence voltage gain is low. ➨FET has slower switching times compare to BJT. The internal junction capacitance of FET is responsible for high delay times.

What are the advantages of FET compared to transistor?

Since base current noise will increase with training time, a FET typically produces less noise than a bipolar transistor (BJT) and is thus found in noise-sensitive electronics such as tuners and low noise amplifiers for receivers VHF and satellite main advantage of fet.

What is the main advantage of FET which makes it more useful in industrial?

What is the main advantage of FET which makes it more useful in industrial applications? Explanation: Because of its small size, the IC chips can be made even smaller which reduces the wear and tear.

What is the main advantage of JFET?

There are some advantages of JFET which are given below,

The JFET can be fabricated in small size area. It is a majority charge carrier device, hence it has less noise. It is a low power consumption device. It can be fabricated in small size area.

What is the main advantage of FET over BJT?

FETs are more temperature stable than BJTs. FETs are generally easier to fabricate than BJTs. Greater numbers of devices can be fabricated on a single chip (i.e., increased packing density is possible). FETs react like voltage-controlled variable resistors for small values of drain-to-source voltage.

Why FET are better than BJT?

It is a majority carrier device. FET is less noisy compare to BJT. It is more suitable for input stages of low level amplifiers.
…
FET.
BJT FET
Low current gain High current gain
Low input impedance Very high input impedance
Low output impedance High output impedance
Medium Noise Generation Low Noise generation

What is the main advantage of a Jeet Mcq?

There are some important advantages of junction field-effect transistor (JFET): The junction field-effect transistor (JFET) is a majority charge carrier device hence it has less noise. The JFET has a high input impedance. The JFET is a low power consumption device.

What are the advantages and disadvantages of JFET?

The JFET can be fabricated in small size area. JFETs occupy less space in circuits due to its smaller size. JFETs are protected to radiation. The JFET has negative temperature coefficient of resistance, so they posses higher Temperature Stability.

What is the disadvantage of JFET?

The main disadvantage of the junction field-effect transistor (JFET) is the relatively low gain-bandwidth product. The performance of JFET goes down as frequency increases due to feedback by internal capacitance.

Why the input impedance of FET is high?

Since the Gate junction is reverse biased and because there is no minority carrier contribution to the flow through the device, the input impedance is extremely high. … The control element for the JFET comes from depletion of charge carriers from the n-channel.

Which of the following option is true for FET?

Detailed Solution
FET BJT
Voltage-controlled device: voltage between gate and source control the current through the device. Current-controlled device: Base current control the amount of collector current
High input resistance Input impedance less than FET
Slower in switching Faster in switching

What is the N-channel FET?

A N-Channel JFET is a JFET whose channel is composed of primarily electrons as the charge carrier. … This is in contrast to P-Channel JFETs, whose channel is composed primarily of holes, which constitute the current flow. A N-Channel JFET is composed of a gate, a source and a drain terminal.

What are the parameters of FET?

The important parameters of the FET at low frequency are the trans- conductance (g,) and the drain resistance (r, = 119,). Both g, and g, are dynamic parameters defined at and around the Q-point and their accurate measurement is the subject of this article.

What is FET impedance?

In FET the high input impedance was provided by the reverse bias of Gate and channel. … This drawback of FET was corrected using MOSFET where an insulating oxide layer was inserted between the gate and substrate to increase the channel impedance.

Which FET has highest input impedance?

FET input impedance:

As the input circuit of FET is reverse biased, FET exhibits a much higher input impedance ( in the order of 100 M 12 ) and lower output impedance and there will be a high degree of isolation between input and output.

What is FET transconductance?

Transconductance is an expression of the performance of a bipolar transistor or field-effect transistor (FET). … For an FET, transconductance is the ratio of the change in drain current to the change in gate voltage over a defined, arbitrarily small interval on the drain-current-versus-gate-voltage curve.

What are the disadvantages of FET?

Disadvantages of FET :
  • They are more costly than junction transistor.
  • Smaller gain bandwidth product compare to BJT.
  • Transconductance is low hence voltage gain is low.
  • It has lower switching time compare to BJT.
  • Special handling is required during installation.
  • When FET performance degrades as frequency increases.

What is the principle of FET?

The FET controls the flow of electrons (or electron holes) from the source to drain by affecting the size and shape of a “conductive channel” created and influenced by voltage (or lack of voltage) applied across the gate and source terminals.

What are the terminals of FET?

A FET has four terminals named Source, Drain, Gate, and Body.

How do you calculate FET transconductance?

Measuring transconductance
  1. Sweep the gate voltage (VGS) over the desired range, while maintaining a constant drain/source voltage (VDS)
  2. Measure the drain current (ID) at each increment step of VGS.
  3. Calculate transconductance (gm) by dividing the small changes in the current ID by the small changes in VGS.