FETs can be called UNIPOLAR devices because the charge carriers that carry the current through the device are all of the same type i.e. either holes or electrons, but not both. This distinguishes FETs from the bipolar devices in which both holes and electrons are responsible for current flow in any one device.
The FET is a semiconductor device with the output current controlled by an electric field. Since the current is carried predominantly by one type of carriers, the FET is known as a unipolar transistor.
Bipolar junction transistor(BJT)
IGBT and BJT are bipolar devices as the name suggest. Meaning of bipolar device both electrons and holes leads to current unlike FET where either electron or hole causes current.
ic made from bjt is known as bipolar ic
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
BJT stands for bipolar junction transistor because it is composed of two types of semiconductors (P and N-type) rather than just one type like a unipolar transistor. This allows for both electron and hole current flow in the device, giving it its bipolar characteristic.
The FET is a semiconductor device with the output current controlled by an electric field. Since the current is carried predominantly by one type of carriers, the FET is known as a unipolar transistor.
Bipolar junction transistor(BJT)
bjt is bipolar device whr fet is unipolar....fet is input resistance thts y fet gain is less compared to bjt..... The applications that will prefer bipolar junction transistors to field effect transistors are applications that require fast switching.
BJT is Bipolar junction transistor FET is Field effect Transistor It is a current controlled device It is voltage controlled device
BJT(Bipolar junction Transistor)-It is bipolar device -meaning both electron and holes are responsible for conduction.-It is mainly used for amplification and switching purposes.-It is current controlled device.MOSFET(Metal Oxide Semiconductor Field Effect Transistor)-It is unipolar device -meaning only one of the charge carriers is responsible for conduction.-It has very high input resistance.Due to this reason it is used in initial stage of Operational amplifier.-It is voltage controlled device.
A Bipolar Junction Transistor (BJT) is called "bipolar" because it uses both types of charge carriers—electrons and holes—for its operation. In an NPN transistor, electrons are the majority carriers in the n-type regions, while holes are the majority carriers in the p-type region. The interaction between these two types of carriers allows the BJT to amplify current. This dual carrier mechanism is what distinguishes BJTs from unipolar devices, like MOSFETs, which rely on only one type of charge carrier.
UJT is the voltage controlled device.in which only one mejority carriers are responsible for current flowing. UJT is one junction transistor and it is three terminal emitter and two base. BJT is the current controlled device. in which both mejority and minority carrier are responsiblefor current flowing. this type of transistor consists of two junction and three terminal these are : emitter , base , collector.
IGBT and BJT are bipolar devices as the name suggest. Meaning of bipolar device both electrons and holes leads to current unlike FET where either electron or hole causes current.
ic made from bjt is known as bipolar ic
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
BJT is a current controlled device because its output current is dependent upon the current in the base while for FET it is controlled by the voltage at the gate terminal of the transistor. BJT is a current controlled device because its base current is not zero while for a FET the gate current is zero