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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 else can I help you with?
How do you calculate the current gain of a transistor JFET?
FETs don't have current gain as no current flows through the gate. The gain of a FET is a voltage gain and is called mu.
What is the alpha beta teta of a bipolar junction transistor?
alpha is the common base current gain = Ic/Ie.beta is the common emitter current gain = Ic/Ib.
Why gain increases in low frequency region in BJT?
Because Beta (current gain) in a transistor is inversely proportional to frequency. Hence it increases as frequency decreases. Also the ac voltage gain is directly proportional to Beta.
What is a cross coupled transistor?
A cross coupled transistor pair are used to increase the gain of the cell.
What is meant by saying at what current is transistor biased?
The saying "at what current is transistor biased" means to ask the current through the transistor when there is no signal present. Typically, a transistor is biased at the center of its linear region, so as to minimize distortion. This, of course, depends on whether or not the transistor is AC or DC coupled, and where the clipping points might be.
How do you calculate the current gain of a transistor JFET?
FETs don't have current gain as no current flows through the gate. The gain of a FET is a voltage gain and is called mu.
What is composite transistor?
A Darlington transistor is a composite transistor. The definition is a combination of two or more transistors that have the purpose of increasing the current gain.
What is the voltage gain of the 2n2222 amplifier?
A: The gain of a transistor is not linear and even that varies from component to component. The gain can vary greatly depending on the Ic current and the load. Manufactures only give out a typical gain for a particular current. As a rule the lower the Ic current the higher the gain. To really find out what a particular transistor characteristics are a tektronik curve tracer is used.
How does a Darlington amplifier work?
A Darlington amplifier consists of two bipolar junction transistors (BJTs) connected in a configuration that allows the current amplified by the first transistor to drive the second transistor. This arrangement results in a very high current gain, as the output current of the first transistor becomes the input current for the second. The input signal is applied to the base of the first transistor, which greatly amplifies it before passing it to the base of the second transistor for further amplification. The overall effect is a significant increase in both current and voltage gain, making it useful in various applications where high gain is required.
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.
What is the current gain value of BC 148 transistor?
The hFe (current gain) on the BC148 ranges from a minimum value of 20 to 100, depending on collector current, with a maximum value of 300.
What are the instruments for the study of the gain of a two stage RC Coupled transistor amplifier?
depends on whether you would like calculate or measured results. if you want calculated resulted, then your best bet would be to use an oscilloscope. if you want calculated results, then there are formulas for finding out the voltage, current, impedance, and individual results from each component using the capacitive reactance, voltage, and type of transistor. are you using a summing transistor, inverting amplifying transistor, amplifying transistor, or a different transistor? also are you using DC or AC voltage or current? you need to tell me what type of transistor you are using?
What should be the value of collector current in terms of DC gain if transistor is in saturation mode?
DC current gain is collector-emitter current divided by base-emitter current. In linear mode, gain is beta, or hFe. In saturation mode, however, the transistor is over-driven and you can no longer relate collector-emitter current to base-emitter current. The transistor operates like a switch, and collector-emitter current is a function of voltage and load impedance only. (Ignoring the relatively small voltage drop.) To maintain saturation mode, the collector-emitter current must be smaller than the base-emitter current times hFe. Often, it is several times smaller, because hFe can vary from transistor to transistor, and your design must account for this variability.
How big is the collector current of a transistor with 100 beta if the serial base resistance is 1Kohm and 1V falls on it?
To calculate the collector current (Ic) of a transistor, we first need to determine the base current (Ib). With a base resistance (Rb) of 1 kΩ and a voltage drop of 1 V across it, the base current is Ib = V/Rb = 1V / 1000Ω = 1 mA. Given that the transistor has a current gain (beta) of 100, the collector current is Ic = beta × Ib = 100 × 1 mA = 100 mA.
What is the alpha beta teta of a bipolar junction transistor?
alpha is the common base current gain = Ic/Ie.beta is the common emitter current gain = Ic/Ib.
What is DC load line of a transistor?
A: A transistor has voltage gain as base current is allow to flow. If the load is constant then a DC mirror azimuth path can be plotted as a function of base current and collector current and that is the load line
