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Why output voltage in common base amplifier is in phase to input voltage?
The output of a common emitter stage is inverted, it is not out of phase.
Why is gain affected when the bypass capacitor is open?
Applied input signal at the base of the amplifier appears across the emitter resistor (RE) due to inter electrode capacitance so it should be bypassed the emitter resistor (RE) through the bypass capacitor (CB). unbypassed signal will be amplified (common emitter amplifier) and reverse back from the emitter to the collector through the base, amplified signal from the emitter to the collector (common emitter amplifier) is 1800 out of phase to the amplified signal from the base to the collector (common base amplifier), so reduced the gain.
What is the phase relationship between the input and output signals of the common collector amplifier?
Common emitter is the only transistor configuration that has an 180 degree phase difference between input and output. Common base and common collector outputs are in phase with the input.***********************************That is incorrect.The output of the common emitter is inverted, there is no phase shift.
Why input gain of an amplifier is doubled from output gain?
The gain of a transister stage is determined by its biasing circuit design. The emitter of a transistor is affected by the input signal on the base. If the base forward biases the transistor, the emitter feels the potential of the colector. If the base reverse biases the transistor, the emitter is isolated from the collector and feels the potential of the emmiter biasing circuit. The output signal at the emmiter is representitive of the signal on the base, 180 degrees out of phase. The amplitude of the output signal will be larger, depending on the biasing circuit design.
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.
What is a common base NPN amplifier?
A common base NPN amplifier is used for high frequency applications as the base minimize oscillations at high frequency, separates the input and output. In a common base NPN amplifier the voltage gain is high, relatively low input impedance and high output impedance compared to the common collector.
Why output voltage in common base amplifier is in phase to input voltage?
The output of a common emitter stage is inverted, it is not out of phase.
How is negative feedback achieved in a single stage transistor amplifier?
A: Feedback is a signal fed back from the output like from collector to the base .
What if base current is zero in a transistor used as an amplifier with common emitter configuration?
output current is zero
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 is gain affected when the bypass capacitor is open?
Applied input signal at the base of the amplifier appears across the emitter resistor (RE) due to inter electrode capacitance so it should be bypassed the emitter resistor (RE) through the bypass capacitor (CB). unbypassed signal will be amplified (common emitter amplifier) and reverse back from the emitter to the collector through the base, amplified signal from the emitter to the collector (common emitter amplifier) is 1800 out of phase to the amplified signal from the base to the collector (common base amplifier), so reduced the gain.
What is the phase relationship between the input and output signals of the common collector amplifier?
Common emitter is the only transistor configuration that has an 180 degree phase difference between input and output. Common base and common collector outputs are in phase with the input.***********************************That is incorrect.The output of the common emitter is inverted, there is no phase shift.
What is a current amplifier?
A current amplifier this a device which heightens the current of the input signal at its output. If we are speaking of semiconductor devices i.e. transistors, than this form of amplification is done so by applying input signal the the base of the transistor, and drawing the output singal from the emitter. This amplifier can also me called an emitter follower. A current amplifier will only yield a gain of less than 1, but the current can be amplified up to 10x the input current.
What is amplifier and what is the general circuit of amplifier?
An amplifier amplifies voltage or current. The most basic amplifier consists of a transistor where a signal is fed into the base and is output to the emitter or collector. For simple, low frequency applications (not RF), it may be simpler to use an operational amplifier (op amp) than designing your own amplifier. Also, the data sheets provide very helpful schematics for creating an amplifier. A very common one is the 741; these are also fairly cheap.
Why input gain of an amplifier is doubled from output gain?
The gain of a transister stage is determined by its biasing circuit design. The emitter of a transistor is affected by the input signal on the base. If the base forward biases the transistor, the emitter feels the potential of the colector. If the base reverse biases the transistor, the emitter is isolated from the collector and feels the potential of the emmiter biasing circuit. The output signal at the emmiter is representitive of the signal on the base, 180 degrees out of phase. The amplitude of the output signal will be larger, depending on the biasing circuit design.
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.
What is an emitter follower?
This is a particular transistor amplifier configuration. In general, the input signal is applied to the base, the collector is connected to a supply voltage, and the output is taken between the emitter and power supply common. One of the characteristics of the emitter follower is the output voltage "follows" the input, but the output is reduced by the Vbe voltage (the voltage drop between base and emitter, approximately 0.7 V for a silicon bipolar transistor).
