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
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.
The input resistance of a trasister is jst like pn junction of a diode which has a breakdown voltage of .7v for silicon and the output resistance is like a reverse bias of a diode and hence the resistance is high
SCR or Silicon Controlled Rectifiers are Bipolar junctions Transistor ( Thyristor Family), SCRs are made of two transistors thats why they PNPN or NPNP devices. The three important parts of transistor are - Emitter, Collector & Base. & the Three Important parts of SCR are - Anode, Cathode & Gate. Use of SCRs- rectification of high power AC & power control applications, such as lamp dimming, regulators and motor control. Use of Transistors - switch, audio, high voltage, amplifiers, switcher
Collector-to-Emitter resistance is high when the transistor is biased off.
Transistor switching times: The turn-on time of switching transistor sum of delay time (td) and rise time (tr). ton = td + tr. Delay time (td): It is defined as the time during which the collector current rises from zero to 0.1ICS.
Yes people still use bipolar junction transistors today because of its high switching speed.
A very high speed bipolar junction transistor having a metal-semiconductor emitter base junction instead of a semiconductor-semiconductor emitter base junction.
The Kirk effect occurs at high current densities in bipolar junction transistors and causes a dramatic increase in the transit time of a transistor.
FET is abbreviation of Field Effect Transistor. This is a transistor in which current is controlled by voltage only and no current is drawn. It is a high input impedence device and is used in computers, telecommunication and control circuits. This transistor is better in certain parameters as compared to BJT, that is Bipolar Junction Transistor.
The Junction Field Effect Transistor (JFET)exhibits characteristics which often make it more suited to a particular application than the bipolar transistor. Some of these applications are: - High Input Impedance Amplifier - Low-Noise Amplifier - Differential Amplifier - Constant Current Source - Analogue Switch or Gate - Voltage Controlled Resistor
The heterojunction bipolar transistor (HBT) is a type of bipolar junction transistor (BJT) which uses differing semiconductor materials for the emitter and base regions, creating a heterojunction. The HBT improves on the BJT in that it can handle signals of very high frequencies, up to several hundred GHz. It is commonly used in modern ultrafast circuits, mostly radio-frequency (RF) systems, and in applications requiring a high power efficiency, such as RF power amplifiers in cellular phones. The idea of employing a heterojunction is as old as the conventional BJT, dating back to a patent from 1951.
high voltage gain :- common base since the ratio of output impedance to the input impermanence is very high in common base mode high current gain :-common collector since it is the ratio of Ie/Ib
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.
An ordinary junction transistor consists of two junctions. In effect a variation of the base to emitter current influences the reverse leakage current at the base to collector junction. The base being common to both junctions. A Field Effect Transistor uses an electric field to narrow the conductive channel thus varying its resistance. A FET has an extremely high input resistance compared with that of a standard junction transistor.
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.
In a transistor a current from low resistance input circuit is transferred to a high resistance output circuit with almost unchanged magnitude. This results in a power gain. Infact the name 'transistor' is coined from 'transfer resistor'
JFET = junction field-effect transistor. The transistor design is to restrict/control the current in the channel by expanding or contracting the depletion region, hence the channel cross-section, with a gate signal. The gate is the junction in JFET, compared with using oxide in an MOSFET.