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Because capacitor not allow to pass dc voltage,but capacitor allow ac voltage and signal.Purpose is to block dc voltage.That is coupling condenser.
Wiki User
∙ 12y ago
Wiki User
∙ 11y agoThe capacitor is there to block any dc voltage that might be applied to the input terminal, which could cause damage or upset the biassing if it was allowed through to the base.
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Why capacitor reduce gain of ce amplifier?
Where is this capacitor in the circuit?A capacitor across the emitter bias resistor actually increases the AC gain because it bypasses that resistor, by increasing the ratio of collector impedance to emitter impedance which determines the amplifier voltage gain.A capacitor across the base input resistor actually increases the AC gain because it bypasses that resistor, by decreasing the attenuation of the input signal by the input circuit network.
Circuit diagram of RC coupled amplifier?
One of the several uses of an RC coupled amplifier is to amplify the given input signal. It makes use of a sinusoidal input signal.
Why you use coupling capacitor in electronic amplifier?
It is used to couple output of one stage to input of next stage
How does an op-amp differ from other amplifier suchas common emitter transistor amplifier?
A: They both use transistors. In actuality before an op amp becomes an op amp a discrete transistor made is made to provide it capabilities before it gets integrated into a substrate chip we call op amp. OP AMP have two input to work as a differential amplifier the input are bases closely match to provide virtual no voltage or current offset. Single ended amplifier has one input its reference is the signal source return.
How does the input resistance of the transistor in the common base amplifier compared to that of a common emitter?
Much lower. Check out electronics sites to get the formulae for each.
What should be the value of capacitor at transistor amplifier circuit input?
at full input, if the transistor is working, the value of capacitor will be 0.
DC blocking in a transistor is achieved by?
Including a series capacitor in the input and/or output circuit of the transistor. If the capacitor in the output circuit is omitted there will be a dc component in the output.
When a pnp transistor is connected in a circuit you can be used as a power amplifier because?
the out put voltage will be much grater then the input voltage.
Why capacitor reduce gain of ce amplifier?
Where is this capacitor in the circuit?A capacitor across the emitter bias resistor actually increases the AC gain because it bypasses that resistor, by increasing the ratio of collector impedance to emitter impedance which determines the amplifier voltage gain.A capacitor across the base input resistor actually increases the AC gain because it bypasses that resistor, by decreasing the attenuation of the input signal by the input circuit network.
When a PNP transistor is connected in a circuit in the manner it can be used as a power amplifier because?
the output voltage will be much larger than the input voltage
When transistor acts as an amplifier then does its output voltage increase or decrease?
That depends on both the input signal and the type of amplifier the transistor is used in.
What is amplifier roll off?
A practical amplifier will contain several components of a "shunt" capacitance inherent in the transistor and physical wiring of the amplifier circuit. As the frequency of the input signal increases, the reactance of these shunt-capacitances will decrease until, at a frequency determined by the value of the shunt-capacitance and the circuit impedance, signal attenuation begins to take place. Thus the shunt capacitances limit the high-frequency response of the amplifier (note that the transistor itself also has inherent limits to it's high frequency amplifying capability). In the case of operational amplifiers, many operational amplifiers are internally compensated by a small capacitor (e.g. about 30pf for a 741). The internal frequency compensation capacitor prevents the operational amplifier from oscillating with resistive feedback.
When a PNP transistor is connected in certain circuit manner it can be used as a power amplifier because?
not sure if this is the answer : the output voltage will be much larger than the input voltage.
Why to short circuit capacitor in small signal analysis of BJT?
if the input signal passes through the biasing resistors, the biasing conditions get altered . To prevent this, the input signal should be directly sent to the amplifier (BJT) .Since a capacitor acts as a short circuit for ac signals,capacitors are placed both in the input side and the output side.
How can an amplifier become an oscillator?
An amplifier can become and oscillator by adding positive feedback from the output back to the input. Positive feedback means that the phase of the signal fed back to the input is the same as the phase of the output signal. In the case of a high frequency oscillator, a tuned circuit (inductor and capacitor) or a quartz crystal in the input circuit will determine the frequency of oscillation.
What happens when high input signal is given to pnp transistor?
A high signal input to a transistor amplifier gives a high signal output provided it stays linear.
What is single tuned voltage amplifier?
it is a circuit consisting of a tuned circuit with a capacitor in parallel with inductor and it is connected to collector terminal in common emitter configuration,, and it is used as frequency receiver
