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The bipolar junction transistor is a current operated device with three terminals, emitter, base, and collector. There are two varieties, NPN and PNP. In the NPN variety, if the base is more positive than the emitter and that junction is conducting (greater than typically 0.7 volts), then the current through that junction will control a larger current through the collector emitter junction, when the collecter is also more positive than the emitter and that junction is also conducting. In the PNP variety, the same thing applies, but reverse positive to negative. You can operate in linear mode, where the base current controls the collector current, or you can operate in saturated (switched) mode, where the base current is enough to pass any collector current. This is all dependent on gain, also known as hFe, or beta.
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∙ 14y ago
Wiki User
∙ 11y agoA unijunction transistor (UJT) is an electronic semiconductor device that has only one junction. The UJT has three terminals: an emitter (E) and two bases (B1 and B2). The base is formed by lightly doped n-type bar of silicon. Two ohmic contacts B1 and B2 are attached at its ends. The emitter is of p-type and it is heavily doped. The resistance between B1 and B2 when the emitter is open-circuit is called interbase resistance.
A special type of diode with a bar shaped base, with a terminal at each end and an emitter in the middle. When biased properly it exhibits a negative resistance region and can amplify. See link.
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∙ 13y agoA: It is a transistor that when saturated it will conduct both ways
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What types of transistors are the following - BJT PCT UJT SBT FET GJT AJT DFT?
The BJT is the bipolar junction transistor, the PCT is the point contact transistor, the UJT is the uni-junction transistor, the SBT is the surface barrier transistor, the FET is the field effect transistor, the GJT is the grown-junction transistor, the AJT is the alloy-junction transistor, and the DFT is the drift field-junction transistor.
Why junction field effect transistor is called as unipolar devices?
Field Effect Transistors (both JFET & MOSFET) are unipolar because they use only one type of current carrier (electrons in N-channel or holes in P-channel), unlike bipolar transistors (both junction & the obsolete point contact) which always use both types of current carriers.
Difference between bjt and ujt?
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.
How many junction transistor have?
3
What applications would prefer the bipolar junction transistors over the field effect transistor?
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.
What a unipolar junction transistor?
uygoi;koppkik
Is the pn junction diode is a bipolar or unipolar?
diode is unipolar
Why FET is called as a unipolar transistor?
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.
Why ordinary transistor is known as bipolar junction transistor?
Transistor is known as bipolar junction becoz it has 2 pole. Input is given to the 2 junction and output is taken from to junction
What types of transistors are the following - BJT PCT UJT SBT FET GJT AJT DFT?
The BJT is the bipolar junction transistor, the PCT is the point contact transistor, the UJT is the uni-junction transistor, the SBT is the surface barrier transistor, the FET is the field effect transistor, the GJT is the grown-junction transistor, the AJT is the alloy-junction transistor, and the DFT is the drift field-junction transistor.
Why junction field effect transistor is called as unipolar devices?
Field Effect Transistors (both JFET & MOSFET) are unipolar because they use only one type of current carrier (electrons in N-channel or holes in P-channel), unlike bipolar transistors (both junction & the obsolete point contact) which always use both types of current carriers.
Is junction transistor and bipolar junction transistor are same?
Yes, the are different names for the same thing.
Why high noise in bipolar junction transistor?
In the case of Bipolar Junction Transistor current conduction is due to both holes and electrons. That's why noise is high in Bipolar Junction Transistor
Difference between bjt and ujt?
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.
How many junction that transistor have?
3
How many junction transistor have?
3
A transistor is in active region when?
a transistor in active region when emitter junction is forward biased nd collector junction is reverse biased
