- #1
It is about common emitter configurations
- Thread starter saranga
- Start date
In summary: This allows for amplification of the input signal. However, without seeing the specific circuit and input/output locations, it is difficult to determine the exact configuration.
- #2
Tom.G
Science Advisor
Gold Member
- 5,374
- 4,194
But you didn't show where the input and output are.
An input signal (if you want gain), changes the applied voltage between Base and Emitter.
The emitter voltage won't change in this circuit because it's grounded. Therefore the input must be the Base.
The only way left to get an output is the Collector and typically the signal is the collector voltage referenced to Ground.
Since the Emitter is used as the reference for both input and output, It is called a common-Emitter configuration.
If you have a circuit with the Base grounded, the signal input is to the Emitter, and output is from the Collector, you have a common-Base configuration.
An input signal (if you want gain), changes the applied voltage between Base and Emitter.
The emitter voltage won't change in this circuit because it's grounded. Therefore the input must be the Base.
The only way left to get an output is the Collector and typically the signal is the collector voltage referenced to Ground.
Since the Emitter is used as the reference for both input and output, It is called a common-Emitter configuration.
If you have a circuit with the Base grounded, the signal input is to the Emitter, and output is from the Collector, you have a common-Base configuration.
- #3
Electron Spin
- 52
- 28
Tom.G said:
Your right Tom, I would guess Rb is a bias Resistor, The Emitter is tied to ground and the Collector to Vcc..Now let's assume the input is tied to the Base and the output is picked off the Rc by convention..If we do, then I would guess it is a CE...
To the OP.. The element that has no input or output and typically tied to grd is the "common", hence, Common Emitter, Base, or Collector..
Again, since the emitter is grounded and the collector has a Rc or load resistor and guessing the base is being fed a bias voltage from the collector, the only element with no in/output would assumably be the emitter..Once again, with a little supposition, this could be a common emitter configuration since the emitter is common to the input and output, and is grounded.
Once again, like Tom said..without the in/output being showed we both are kinda' guessing here saranga...
Sorry for the redundancies in advance...
Tom.G said:
^^^^^^^^^
This definition, right here.
- #4
saranga
- 13
- 0
thanks it should be my faultTom.G said:
- #5
saranga
- 13
- 0
thank you,no your discription is effective.Electron Spin said:Your right Tom, I would guess Rb is a bias Resistor, The Emitter is tied to ground and the Collector to Vcc..Now let's assume the input is tied to the Base and the output is picked off the Rc by convention..If we do, then I would guess it is a CE...
To the OP.. The element that has no input or output and typically tied to grd is the "common", hence, Common Emitter, Base, or Collector..
Again, since the emitter is grounded and the collector has a Rc or load resistor and guessing the base is being fed a bias voltage from the collector, the only element with no in/output would assumably be the emitter..Once again, with a little supposition, this could be a common emitter configuration since the emitter is common to the input and output, and is grounded.
Once again, like Tom said..without the in/output being showed we both are kinda' guessing here saranga...
Sorry for the redundancies in advance...
^^^^^^^^^
This definition, right here.
- #6
lychette
- 413
- 73
Electron Spin said:Your right Tom, I would guess Rb is a bias Resistor, The Emitter is tied to ground and the Collector to Vcc..Now let's assume the input is tied to the Base and the output is picked off the Rc by convention..If we do, then I would guess it is a CE...
To the OP.. The element that has no input or output and typically tied to grd is the "common", hence, Common Emitter, Base, or Collector..
Again, since the emitter is grounded and the collector has a Rc or load resistor and guessing the base is being fed a bias voltage from the collector, the only element with no in/output would assumably be the emitter..Once again, with a little supposition, this could be a common emitter configuration since the emitter is common to the input and output, and is grounded.
Once again, like Tom said..without the in/output being showed we both are kinda' guessing here saranga...
Sorry for the redundancies in advance...
^^^^^^^^^
This definition, right here.
Completely agree...common emitter
Related to It is about common emitter configurations
What is a common emitter configuration?
A common emitter configuration is a type of electronic circuit in which the emitter terminal of a bipolar junction transistor (BJT) is connected to both the input and output of the circuit. This configuration is commonly used in amplifiers and signal processing circuits.
What are the advantages of a common emitter configuration?
One advantage of a common emitter configuration is that it provides high voltage gain. It also offers good input-output isolation, as the input signal is not directly connected to the output. Additionally, this configuration has a relatively low output impedance, which allows it to drive low-impedance loads.
What are the disadvantages of a common emitter configuration?
One disadvantage of a common emitter configuration is that it has a non-linear response, which can result in distortion of the output signal. It also has a relatively low input impedance, which can affect the performance of the circuit when connected to high-impedance sources. Additionally, this configuration has a high output impedance at high frequencies, making it unsuitable for high-frequency applications.
How does a common emitter configuration work?
In a common emitter configuration, the input signal is applied to the base terminal of the BJT, while the output is taken from the collector terminal. The emitter terminal is connected to a common ground or reference point. The input signal causes a small current to flow through the base-emitter junction, which in turn controls the larger current flowing through the collector-emitter junction, resulting in amplification of the input signal.
What are the applications of a common emitter configuration?
A common emitter configuration is commonly used in audio amplifiers, radio frequency (RF) amplifiers, and other signal processing circuits. It is also used in switching circuits, where the BJT is operated in saturation and cutoff regions to control the flow of current. Additionally, this configuration is used in voltage regulators and other power management circuits.