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FET's (field effect transistors) are unipolar devices because unlike BJT's that use both electron and hole current, they operate only with one type of charge carrier. BJT is a current-controlled device; that is the base current controls the amount of collector current. FET is a voltage-controlled device, where voltave between two of the terminals (gate and source) controls the current through the device. BJT's have a low input impedance ( ~1k -3k ohms), while FET's have a very high input impedance (~10^11 ohms). Consequently FET's have a lower power consumption. BJT's produce more noise than FET's .
FET's have a slower switching speed . BJT's are subject to thermal runway while FET's are immune to this problem. BJT's have a higher cutoff frequencey and a higher maximum current then FET's. FET's are easy to fabricate in large scale and have higher element density the BJT's.
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What is the difference between fet and ujt?
The structure of a UJT is quite similar to that of an N-channel JFET. The main difference is that P-type (gate) material surrounds the N-type (channel) material in case of JFET and the gate surface of the JFET is much larger than emitter junction of UJT.
What is the difference between BJT and NPN transister?
Mainly there are two types of transistors. They are BJT (Bipolar Junction Transistors) and FET(Field Effect Transisters). In BJT, there are two types called PNP and NPN. Actually NPN means a BJT transister.
Why bjt is bipolar?
Bjt is bipolar because in bjt the conduction of current is due to the electrons as well as holes
What is the difference between clucth and coupling?
difference between clucth and coupling
What is the difference between a socket and a coupling?
difference between coupling and socket
What is the difference between jfet and mosfet?
1-BJT is bipolar while JFET is unipolar. 2-BJT has low input impedence while JFET has high input impedence. 3-JFET has low power discipation as compared to BJT. 4-JFET has low noise as compared to BJT. 5-BJT is current controlled while JFET is voltage controlled. 6-JFET is mostly used in digital circuits.
What is bjt and jfet?
BJT is Bipolar junction transistor FET is Field effect Transistor It is a current controlled device It is voltage controlled device
What are the advantages and disadvantages of JFET over BJT?
An advantage of JFET is stable high current operation. A disadvantage of JFET is low capacitance. An advantage of BJT is constant voltage operation. A disadvantage of BJT is low thermal conductance.
What are current controllable devices?
BJT is a example for current controll device. And JFET is a voltage controlled device.
Advantages of fet over bjt?
mainly i will tell ttwo advantages:- 1)in FET "thermal runaway" never occurs but in bjt it occurs easily...thermal runaway means overheating and damage of fet due to different biasing voltages.. 2) since FET is a unipolar device so only one carrier type is required here ,but bjt is a bipolar device .. 3) FET is smaller in size than BJT of same rating. i mean to say that at the place of 10 bjts we can use 90 FETs ..so area cosumption is less
What is the difference between fet and ujt?
The structure of a UJT is quite similar to that of an N-channel JFET. The main difference is that P-type (gate) material surrounds the N-type (channel) material in case of JFET and the gate surface of the JFET is much larger than emitter junction of UJT.
What is the difference between BJT and NPN transister?
Mainly there are two types of transistors. They are BJT (Bipolar Junction Transistors) and FET(Field Effect Transisters). In BJT, there are two types called PNP and NPN. Actually NPN means a BJT transister.
What can transistors be?
either field effect (JFET, MOSFET) or junction (BJT) or point contact (usually considered obsolete)either small signal or high powereither electron majority carrier (N-channel FET, NPN BJT) or hole majority carrier (P-channel FET, PNP BJT)either linear (used in amplifier and oscillator circuits) or switching (used in digital logic circuits)etc.
How jfet works?
A Jfet works by applying voltage to the drain of the jfet. A jfet will then conduct across from drain to source.
Transistors can be either what or what?
either field effect (JFET, MOSFET) or junction (BJT) or point contact (usually considered obsolete)either small signal or high powereither electron majority carrier (N-channel FET, NPN BJT) or hole majority carrier (P-channel FET, PNP BJT)either linear (used in amplifier and oscillator circuits) or switching (used in digital logic circuits)etc.
How is a transistor used as a switch?
A transistor (bipolar junction transistor BJT) will only conduct in ONE DIRECTION. And the voltage drop is not Ohmic - it is *NOT* strictly related to current flow. If you're referring to a Field-Effect Transitor (JFET, IGFET, MOSFET, etc), then the device may be able to be used in a bidirectional circuit. But the question stated "transistor", which is understood to be a BJT.
How a transistor use as a switch?
A transistor (bipolar junction transistor BJT) will only conduct in ONE DIRECTION. And the voltage drop is not Ohmic - it is *NOT* strictly related to current flow. If you're referring to a Field-Effect Transitor (JFET, IGFET, MOSFET, etc), then the device may be able to be used in a bidirectional circuit. But the question stated "transistor", which is understood to be a BJT.
