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Why in common collector amplifier however you change value of resistance not amplifier in voltage?
The question does not quite make sense. It sounds like you are asking why does changing the emitter resistor in a class C common collector amplifier not affect the output voltage? If so, the answer is that the common collector is an emitter follower, meaning that the emitter will follow the base, less the base-emitter junction voltage, within the limits of hFe. The resistor is simply there to ensure output biasing when the base voltage goes low.
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What will happen to voltage divider circuit if emitter resistance is greater than collector resistance?
The gain of a class A, common emitter BJT amplifier, a fairly standard configuration, is defined as collector resistance divided by emitter resistance, or as hFe, whichever is less. Assuming that we are operating in a linear mode, and hFe is not a limiting factor, then the emitter resistance being greater than the collector resistance simply means that the gain is less than one.
Why mostly a transister is used as amplifier than diode?
A diode is not an amplifier. It is a rectifier with asymmetrical voltage breakdown voltages. Usually the forward voltage is around 0.6V to 0.7V (silicon), and the reverse voltage is smaller than breakdown voltage, which is much higher. A transistor can be used as an amplifier, by taking into account the fact that the voltage breakdown curves vary, usually collector-emitter, as a function of some other current, usually base-emitter, but this depends on the class of the amplifier and whether or not the transistor is driven into saturation.
What is meant by biasing in a single stage ce amplifier?
Biasing in a single stage common-emitter amplifier means to place the base-emitter current at a point where the collector-emitter current is in the middle of the transistor's linear range.First, you pick the target range and output impedance of the amplifier, picking the collector and emitter resistors. The gain of the stage is collector resistance divided by emitter resistance, limited by available hFe. You want to try to pick a resistor pair that will place the collector voltage in the center of the desired range, while keeping the desired operating current where you want it.Then, you pick the base resistor divider pair such that the base voltage is the forward bias drop of the base-emitter above (NPN) or below (PNP) the emitter voltage. You find that emitter voltage by considering the collector voltage, along with the operating current and the collector and emitter resistors. (Its straightforward Ohm's law, considering that the collector-emitter forms the third resistor in the divider chain.) You have to consider hFe in this calculation, as well as realizing that the two base resistors will form the input impedance of the stage. (Well, actually, base-emitter current is included in the input impedance calculation, but that is usually a small contribution if the hFe is high enough.)Then you need to consider the power dissipation in the stage, and make sure that the transistor can handle that, and that hFe will not drift unacceptably under temperature. (Stable designs are such that the hFe is far greater than the ratio of collector resistance over emitter resistance, so that your limits are based on ratio, and not on hFe. Problematic designs are when the desired gain is greater than hFe, such as when the emitter resistance is zero - this makes gain equal to hFe, and introduces the possibility of thermal runaway.)
What are the application of voltage shunt amplifier?
Applications of Voltage shunt feedback amplifier?
May power amplifier a voltage amplifier?
A power amplifier may also boost voltage; in audio equipment, power amplifiers often have a dial on the front that is used to control the input voltage gain. A simple power amplifier is composed of a single transistor; this type of configuration cannot provide voltage amplification as well. A voltage amplifier stage is needed. So the above example of an audio power amplifier is actually a voltage amplifier stage, followed by one or more power amplifier stages.
Application of a common - collector amplifier circuit?
Common collector amplifier can be used as a voltage buffer and in impedance matching
Which bjt transistor amplifier can be used as a voltage buffer?
the common collector can use as voltage buffer
Main use of a Common collector transistor amplifier is?
No voltage gain
What will happen to voltage divider circuit if emitter resistance is greater than collector resistance?
The gain of a class A, common emitter BJT amplifier, a fairly standard configuration, is defined as collector resistance divided by emitter resistance, or as hFe, whichever is less. Assuming that we are operating in a linear mode, and hFe is not a limiting factor, then the emitter resistance being greater than the collector resistance simply means that the gain is less than one.
Input resistance and output resistance of Voltage series feedback amplifier?
output resistance decreases and input resistance increases
How transistor produce 180 degree phase shift?
In the common emitter configuration, a class A amplifier, an increase in base voltage (the input) leads to an increase in base-emitter current which leads to a proportionately larger increase in base collector current. That pulls the collector towards the emitter, which decreases the collector voltage. Since the collector is the output, this configuration is an inverting amplifier.
Why phase shift of ce configuration is 180 out of phase while cc has same phase?
In a ce amplifier, an increase of base voltage causes the collector current to rise. This causes an increased voltage drop through the collector load resistor, so the collector voltage drops. With a cc amplifier the increase in current causes more voltage across the emitter load resistor, therefore the emitter voltage rises.
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 advantages and disadvantages in using common collector amplifier?
Current gain. At the cost of no voltage gain.
Why output of common emitter amplifier is inverted?
In a common emitter amplifier, the base-emitter current causes a corresponding collector-emitter current, in the ratio of hFe (beta gain) or collector resistance over emitter resistance, which ever is less. Since this ratio is usually greater than one, the differential collector current is greater than the differential base current. This results in amplification of the base signal. As you increase the base-emitter current, the collector-emitter current also increases. This results in the collector being pulled towards the emitter, with the result that the differential collector voltage decreases. This results in inversion of the base signal.
Why we kept VOLTAGE collector to emitter half of voltage vcc?
We bias the common emitter amplifier to have a collector-emitter voltage of one half of Vcc in order to set the operating point halfway between the two extremes.
How does a transistor function as an amplifier?
A: The small base current will control the collector current flow by adding a resistor this changes of current flow will be evident as a voltage amplifier.
