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Beta is current gain of that transistor,whatever be the input the trasistor. we will get the output multiplied by the beta.
for example in CE amplifer if Base current is 10 microampere and beta of that transistor is 100 then collector current would be 1mA i.e. 100 times greater than input current
Wiki User
∙ 14y ago
Wiki User
∙ 14y agoWhen taken in context with Betta splendens or Siamese fighting fish is of no use whatsoever.
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How does using a transistor with a different beta affect the operation of the common emitter amplifier?
Gain, in the common emitter amplifier, is beta (hFe) or collector resistance divided by emitter resistance, whichever is less. Substituting a different beta (hFe) transistor will affect gain, if hFe is less, or increase stability and design margin, if hFe is greater.
What is Stability factor of circuit?
A: A circuit to be useful to do work must be stable with the environment and also with reliable circuit performance. A circuit that is allow break into oscillation or other criteria is not stable therefore not much useful.
How do i Calculate base current from collector current and resistance?
Ib =Ic /beta beta is the gain factor of the amp.
What a need for analyzing transistor circuits using different parameter?
At different parameters the input and output relation differs ,amplification factor varies across the various configuration of transistor. To know how to use the transistor weather as a switch or as an amplifiers analyzing it across all the parameters is important.
Can you interchange the collector and emitter terminals in a transistor?
Yes, but the results will be quite unsatisfactory due to differences in the dopant profiles of the collector and emitter.In the normal connection, beta will usually be in the range of 20 to 150 and the transistor will operate at the frequency given in the databook. The same transistor with the collector and emitter interchanged, beta will usually be in the range of 3 to 10 and the transistor will be much slower than the frequency given in the databook. Other parameters will also be degraded below databook values.It should not in general damage the transistor though, but some transistors having very low emitter-base reverse breakdown voltage will have their emitter-base junction burned out when the emitter is used as the collector, in some circuits.
What is the relation between transistor current?
transistor current is dependent on a factor known as Beta of the transistor. a darlington pair has a large Beta(10,000) , a small signal transistor such as the 2n3904 has a small beta of around 100. the beta of a transistor determines the amount of current that flows from collector to emitter ( bipolar transistors) for each amount of current that flows into the base you get a hundred fold increase between collector and emitter (2n3904), so you insert 1 ma (milliamp) into the base, you get 100 ma out the emitter. there is a doped region in the middle of the transistor that expands when current is applied to the base, this expansion allows more current to flow from collector to emitter (npn). there are many types of transistors but they all employ basically the same function. The mathematics involved is a bit more complicated but I speaking in general terms here to avoid getting someone lost.
How do darlington transistors work?
A Darlington transistor it may contain one or more transistor in its case. the purpose is to amplify current by beta multiplication.
What is darlington configuaration?
A Darlington pair uses two transistors connected to behave as a single transistor with a very high current gain (beta). Transistor-1 has its collector connected to the collector of transistor-2. Transistor-1 has its emitter connected to the base of transistor-2. The base of transistor-1 with the emitter and collector of transistor-2 is used as a single transistor.
How does using a transistor with a different beta affect the operation of the common emitter amplifier?
Gain, in the common emitter amplifier, is beta (hFe) or collector resistance divided by emitter resistance, whichever is less. Substituting a different beta (hFe) transistor will affect gain, if hFe is less, or increase stability and design margin, if hFe is greater.
What is hfe and hfc in transistor?
I don't know about hfc, but hFE is the amplification factor by which the transistor amplifies the base current. Therefore, if hFE is 100, the base current is amplified by a factor of 100.
Is a diode like a transistor?
No. A diode is not like a transistor, and a transistor is not like (two) diode(s). Taken in isolation, the emitter-base and collector-base junctions of a transistor appear to be diodes, but they are coupled together so that the base-emitter current affects the collector-emitter current.
How do you calculate the current gain of a transistor?
Bipolar transistor current gain is also called "Beta," or the h-parameter "hfe." beta = current_out / current_in The beta of a BJT is mostly determined by the thickness of the Base region, and by the excess doping in the Emitter relative to the Base. A thin Base and a heavily-doped Emitter leads to a high value for current gain. In a BJT, beta = Ic / Ib In a FET, beta is usually taken as infinity, since no current flows in or out of the gate. Beta is an impirical number. It means nothing unless the Ic is known or the load. It can have a beta from 1000 to 10 it all depends on the load.
What is Stability factor of circuit?
A: A circuit to be useful to do work must be stable with the environment and also with reliable circuit performance. A circuit that is allow break into oscillation or other criteria is not stable therefore not much useful.
What is the difference between a transistor used as a switch and an amplifier?
A transistor used as a switch is operated in saturated mode, where the ratio of base-emitter current over collector-emitter current is far more than hFe, or beta gain. The transistor is either fully on or fully off in this mode. A transistor used as an amplifier is operated in linear mode, where the ratio of base-emitter current over collector-emitter current is equal to or less than hFe, or beta gain. The transistor is partially on in this mode, and is operating as a current controlled current sink.
Does transistor current gain increase or decrease with temperature?
In general, transistor current gain (beta) increases by approximately 0.7% per degree centigrade above room temperature. The current gain of a heated device may be found according to: beta(T) = beta(25 degrees C)*(1+0.007(T-25)) This is why robust circuits are designed such that there is no dependence on beta.
Why negative feedback amplifier is preferred to positive feedback amplifier?
The negative feedback tends to stabilize the circuit; positive feedback would make it more unstable. For example, the "beta" of a transistor OF THE SAME SERIES - this is basically the amplification factor - may vary between 100 and 1000. With negative feedback, the circuit is hardly affected by these changes in beta - at the cost of a reduced amplification.
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.
