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That's referred to as, `hfe` in transistor parlance. Essentially, since a transistor is a current operated device, the gain means that for every milliamp in at the base, the gain (times X) will be amplified through the junction of the collector/emitter.
For instance, take a transistor with a gain of 30. One milliamp in at the base will allow the transistor to pass 30 milliamps through the collector/emitter junction. Of course, there will also be a resultant voltage drop of 1.2 volts over all. -.6 volts for the base and -.6 volts through the collector/emitter junction. Remember, you're working with a current controlled device, and not a voltage controlled device like an op-amp.
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What is the Frequency response of common emitter amplifier?
The voltage gain is a measure of the amplified output available at the collector terminal divided by the voltage measured on the base. This if you have 10 mV applied to the base and voltage of 1 volt at the collector the voltage gain is 100ANSWERThe maximum voltage gain of a common emitter amplifier is dependant on the transistor itself. Some have only a very small voltage gain such as in Radio Frequency Power transistors. These are almost all used as common emitter circuits for bipolar transistors or common source for FETs.. On the other hand some darlington transistors can have common emitter gains of hundreds of thousands. If the stage has an unbypassed emitter resistor, the voltage gain is equal to Rload/RE, (Rload is the parallel value of the resistance from collector to the supply and the resistance of the load).If the emitter resistance is bypassed, the value of resistance to be used for RE is the internal Re which is equal to 25mV/Ie
What are the characteristics of a common emitter amplifier?
There are a number of characteristics found in a common emitter amplifier. Not only are the parameters considered, but also their performance. Characteristics and performance are: voltage gain/ medium; current gain/ medium; power gain/ high; input / output phase relationship/ 180 degrees; input resistance/ medium; and output resistance/ medium.
What does the switch on a guitar do?
The "switch" on an electric guitar generally switches between the pickups, for different sounds.
What is gain on guitar amps?
Gain, usually measured in decibels, is the ratio of output to input power. A more sensitive amplifier will have higher gain settings requiring less input signal.
How is automatic gain control bias voltage developed in a valve superhet radio reciver circuit?
The signal is changed to dc in the AGC circuit to change the gain. A weak signal will increase gain.
What is the symbol for current gain?
Current gain configuration is the change in collector current divided by the change in the emitter current. Its symbol is hfe, or h-parameter.
what is the Primary function of the common collector amplifier?
current gain
What is the gain of bc 547?
If you want to find DC gain (Hfe) of a BJT transistor like BC547, then you need to look in its datasheet. You can easily find a datasheet for BC547 just by googling it. Once you found it, then you will find a graph for DC current gain in the datasheet. The x-axis of the graph will be the collector current (Ic) and the y-axis will be the gain (Hfe). As you will see from the graph the gain is dependent on the collector current Ic. Therefore first determine what collector current you want to be flowing, then use the graph to find what the DC gain will be. Then you can find what base current Ib you need to inject in order to establish the necessary collector current Ic. The relationship is Ic = Hfe*Ib.
How do i Calculate base current from collector current and resistance?
Ib =Ic /beta beta is the gain factor of the amp.
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 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.
Why does a CE amplifier have a high gain?
GAIN is a function of load current but basically a small current in the base will make a big change of collector current therefore making a transistor a voltage amplifier as opposed to a current amplifier
Why base current is very small?
Small is relative term, current gain of the transistor decides how small base current would be than collector current. Most of the emitter current of electrons diffuses through the thin base into the collector. Moreover, modulating the small base current produces a larger change in collector current.Small is relative term, current gain of the transistor decides how small base current would be than collector current. Most of the emitter current of electrons diffuses through the thin base into the collector. Moreover, modulating the small base current produces a larger change in collector current.Small is relative term, current gain of the transistor decides how small base current would be than collector current. Most of the emitter current of electrons diffuses through the thin base into the collector. Moreover, modulating the small base current produces a larger change in collector current.
Why common collector amplifier current gain is equal to beta?
Actually the current gain is equal to Beta+1, not Beta. The current from/into the emitter is the sum of the current into/from the collector and base. Of course this assumes linear operation.For a proof: Ie + Ib + Ic = 0Ic = Beta * IbIe + Ib + Beta * Ib = 0Ie + (Beta + 1) * Ib = 0Ie = -(Beta + 1) * Ib
What are the advantages and disadvantages in using common collector amplifier?
Current gain. At the cost of no voltage gain.
What is the typical base-to-collector amplification factor of CA3046 BJT?
The typical base-emitter gain (beta or hFE) of a CA3046 is 100, at an emitter current of 100ma. This translates to a base-collector gain (alpha) of 0.99.
What does the electronic term Vb mean?
Base voltage in a transistor. There is also Vc (Collector voltage), Ve(Emitter voltage), Ic(Collector current), Ib(Base current), Ie(Emitter current), Vcc(Supply voltage), and Hfe (Forward current gain)
