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Collector-to-Emitter resistance is high when the transistor is biased off.

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Q: The value of r when a transistor is biased to cut off is -?
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When both junctions of NPN diode are reverse biased then the diode is in which mode?

Transistor will be in OFF mode.


What is meant by beta cutoff frequency?

The beta cut off frequency is the frequency at which the current amplification of an amplifier transistor drops to three decibels below its value at 1 kilohertz. This is used in electronic engineering.


What is description of Bc547 transistor?

BC547is an NPN bi-polar junction transistor. A transistor, stands for transfer of resistance, is commonly used to amplify current. A small current at its base controls a larger current at collector & emitter terminals.BC547is mainly used for amplification and switching purposes. It has a maximum current gain of 800. Its equivalent transistors are BC548 and BC549.The transistor terminals require a fixed DC voltage to operate in the desired region of its characteristic curves. This is known as the biasing. For amplification applications, the transistor is biased such that it is partly on for all input conditions. The input signal at base is amplified and taken at the emitter. BC547 is used in common emitter configuration for amplifiers. The voltage divider is the commonly used biasing mode. For switching applications, transistor is biased so that it remains fully on if there is a signal at its base. In the absence of base signal, it gets completely off.


What is cutoff region in transistor?

The cutoff region is when the transistor doesn't have sufficient base current to drive a larger current from emitter to collector. Therefore, the transistor does not turn on and stays shut off.


What is a Programmable unijunction transistor?

PUT: programmable unijunction transistor It is a device like the thyristor only the gate is connected to the N type material near the anode. It is usually used in time delay, logic and SCR trigger circuits In the PUT, Gate is always positively biased w.r.t cathode. When anode voltage exceeds the gate voltage by about 0.7 V, first junction that is the junction right after the anode gets forward biased and PUT turns on. When anode voltage becomes less than the gate voltage, PUT is turned off.

Related questions

The value of r when a transistor is biased to cut off is?

1


What is the value of Ic when transistor is in cut off region?

Zero, or close to zero.


When both junctions of NPN diode are reverse biased then diode is in which mode?

Transistor will be in OFF mode.


When both junctions of NPN diode are reverse biased then the diode is in which mode?

Transistor will be in OFF mode.


When the both junction of npn diode is reverse biased then the diode in which mode?

Transistor will be in OFF mode.


When does the transistor gets cut-off?

the magical number is .6v


Does a transistor in cut-off region acts as an open switch?

No


How is an transistor used as a amplifier?

Voltage is applied between the collector and emitter. A signal is applied between the base and emitter. The input signal will control how much the transistor turns on and the larger current flowing across the Collector/Emitter will be the same, but larger, than the input. Therefore amplified.To keep the transistor switched on and to prevent the input signal switching it off, the transistor has to be biased on. This is usually done with a network of resistors on the base, raising the voltage to keep it conducting.


When operated in cut off and saturation mode the transistor acts like what?

switch


What is transistor as a switch?

transistor is a nonlinear device. it will acts as a swicth based on the cut in voltage we can easily identifying the the transistor is in forward or reverse bias.in forward it is 'on' reverse bias 'off'.


How many states does a transistor have?

A transistor can be in three conditions or states. It can be active (at a voltage higher than the emitter), in saturation or cut off (no current).


Why biasing a transistor?

We bias transistors in order to determine the modes of operation ( that is whether the transistor is operating in the active cut off or the saturation regions).