Compare between BJT and FET on the basis of (i) Biolar/Unipolar (ii) Tharmal Runaway (iii) Noise (iv) Applications

Compare between BJT and FET on the basis of (i) Biolar/Unipolar (ii) Tharmal Runaway (iii) Noise (iv) Applications
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1 Answer

Answer :

Parameter
BJT
FET
Bipolar/Unipolar
It is bipolar device i.e. current in this device is carried by electrons and holes.
It is unipolar device i.e. current in this device is carried by either electrons or holes.
Thermal Runaway
Can occur
Cannot occur
Noise
More
Less
Applications
Automatically controlled switches, TTL circuits, amplifiers, drivers circuits etc.
FETs are widely used as input amplifiers in oscilloscopes, electronic voltmeters and other measuring and testing equipment because of their high input impedance.
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in which BJT operating region both the junctions are reverse biased?

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Last Answer : Active , Saturation , Cut-off region of operations in BJT.

Does BJT have second breakdown problem?

Last Answer : Yes BJT have second breakdown problem.

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Last Answer : BJT have three terminals Base, emitter and collector.

Explain the on state losses in power BJT.

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why IGBT is preferred as a power switch over both power BJT and MOSFET?

Last Answer : Because it has a higher switching frequency and heat tolerance.

why igbt is used instead of bjt and mosfet?

Last Answer : ON state losses of IGBT is less as compared to MOSFET and BJT.

why bjt is called current controlled device?

Last Answer : In  BJT  there  is  movement  of   electrons  and  holes   accros  the  junctions  which  is  basicaly  current  flow.

when bjt is in cutoff ?

Last Answer : When Q-point is at cut off region means it is just above the horizontal axis VCE

what is bjt biasing?

Last Answer : The proper flow of zero signal collector current and the maintenance of the proper collector emmiter voltage during passage of single called as transistor biasing

bjt what is beta ?

Last Answer : Beta is the current gain which is the ratio of collector current to base current.

bjt is active or passive?

Last Answer : BJT control the flow of electron so it is a active device.

is bjt a voltage controlled device ?

Last Answer : No, BJT is a current controlled device .

what does bjt stand for?

Last Answer : Bipolar junction transistor

what are bjt amplifiers used for?

Last Answer : Transformer coupled amplifiers Direct coupled amplifiers Multistage amplifiers Darlington amplifiers Emmiter follower

what are bjt transistors?

Description : what are bjt transistors?

Last Answer : Bjt transistor is a type of transistor which  uses both electrons and hole charge carrier.bjts are used as switches and amplifiers.They amplify currents.