In a common-emitter (C-E) configuration, an emitter resistor is used primarily to provide temperature stability and improve linearity of the amplifier. It helps to stabilize the operating point by reducing the effects of temperature variations and transistor beta fluctuations. Additionally, the emitter resistor introduces negative feedback, which enhances linearity and bandwidth while reducing distortion. However, it also reduces the overall voltage gain of the amplifier.
A common-emitter (CE) transistor amplifier circuit typically includes a NPN transistor, a biasing resistor network, an input coupling capacitor, and an output coupling capacitor. The input signal is fed into the base of the transistor through the coupling capacitor, while the collector is connected to a power supply through a load resistor. The emitter is usually grounded or connected to a resistor. This configuration allows for voltage amplification, where the output is taken from the collector.
It depends on where the capacitor is located. If it is across the emitter resistor, then the gain of the CE amplifier will be higher at higher frequencies.Remember that gain in the CE amplifier is collector resistance divided by emitter resistance, or hFe, whichever is lower. Placing a capacitor across the emitter resistor will serve to make the effective resistance smaller at higher frequencies, resulting in increased gain, up to the limit of hFe.If this is not the intended location of the capacitor, then please restate the question and provide the capacitor location.
Gain in a CE configuration of a BJT is collector resistance divided by emitter resistance, subject to the limit of hFe. The emitter bypass capacitor will have lower impedance at high frequency, so the gain will be higher at higher frequency, making this a high-pass amplifier.
A bipolar transistor can be used in different configurations in linear electronic design. Most well known is the common emitter CE configuration with a base current as input signal resulting in a collector signal multiplied by the current gain factor. The second configuration is known as the emitter follower or common collector configuration. Here the input signal is in the form of a voltage between the base and the common connection. The output signal is found in the form of a voltage at the emitter with a relative low output impedance. The voltage swing at the input is almost as large at the output where the input impedance equals the product of the current gain factor and the emitter resistance. The third configuration is known as common base CB. Here the input current at the emitter almost equals the output current at the collector. The current gain is nearly equal to 1.
In a common emitter (CE) configuration, the output characteristics used for switching action are primarily the active region and the saturation region. When the transistor is in the active region, it can amplify signals, while in the saturation region, it acts as a closed switch, allowing maximum current to flow. The transition between these two regions is crucial for effective switching, where the transistor is turned on (saturation) or off (cut-off) to control the output.
I think you mean a common emitter amplifier, which is an amplifier of voltage. Emitter-follower or common collector amplifiers are used to match impedances, or to amplify power or current. The emitter-follower is a type of common emitter circuit that has a resistor between the emitter and ground. The output signal is taken from the point between the emitter and its resistor.
Common Emitter(CE) Configuration possess largest voltage gain among the three(CE CB CC).
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.
A common-emitter (CE) transistor amplifier circuit typically includes a NPN transistor, a biasing resistor network, an input coupling capacitor, and an output coupling capacitor. The input signal is fed into the base of the transistor through the coupling capacitor, while the collector is connected to a power supply through a load resistor. The emitter is usually grounded or connected to a resistor. This configuration allows for voltage amplification, where the output is taken from the collector.
comparerission between CB,CC&CE
because in ce configuration value of input voltage requried to make the transistor on is very less value of the output voltage or output current
The common emitter configuration works best because of the way the segments of transistors are biased, and the fact that there are more carriers in the collector than in the emitter.
It depends on where the capacitor is located. If it is across the emitter resistor, then the gain of the CE amplifier will be higher at higher frequencies.Remember that gain in the CE amplifier is collector resistance divided by emitter resistance, or hFe, whichever is lower. Placing a capacitor across the emitter resistor will serve to make the effective resistance smaller at higher frequencies, resulting in increased gain, up to the limit of hFe.If this is not the intended location of the capacitor, then please restate the question and provide the capacitor location.
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.
Gain in a CE configuration of a BJT is collector resistance divided by emitter resistance, subject to the limit of hFe. The emitter bypass capacitor will have lower impedance at high frequency, so the gain will be higher at higher frequency, making this a high-pass amplifier.
A bipolar transistor can be used in different configurations in linear electronic design. Most well known is the common emitter CE configuration with a base current as input signal resulting in a collector signal multiplied by the current gain factor. The second configuration is known as the emitter follower or common collector configuration. Here the input signal is in the form of a voltage between the base and the common connection. The output signal is found in the form of a voltage at the emitter with a relative low output impedance. The voltage swing at the input is almost as large at the output where the input impedance equals the product of the current gain factor and the emitter resistance. The third configuration is known as common base CB. Here the input current at the emitter almost equals the output current at the collector. The current gain is nearly equal to 1.
It can be used as a feedback and to ground unwanted signals and frequencies