It is about common emitter configurations

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The discussion revolves around the classification of a transistor configuration, specifically whether it is a common emitter or common collector setup. Participants clarify that in a common emitter configuration, the emitter is grounded and serves as a reference point for both input and output, with the input typically applied to the base and the output taken from the collector. There is some confusion regarding the input and output connections, which are not clearly shown in the original diagram. The consensus is that if the emitter is grounded and the base is receiving a bias voltage, it supports the common emitter classification. Overall, the importance of identifying the input and output in circuit diagrams is emphasized for proper classification.
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this diagram is said to be an example for common emitter configuration,but to me ,it is just seem like common collector configuration..would someone explain this?​
 

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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.
 
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Tom.G said:
But you didn't show where the input and output are.

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...:oldsmile:

Sorry for the redundancies in advance...
Tom.G said:
Since the Emitter is used as the reference for both input and output, It is called a common-Emitter configuration.

^^^^^^^^^

This definition, right here.
 
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Tom.G said:
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.
thanks it should be my fault
 
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...:oldsmile:

Sorry for the redundancies in advance...

^^^^^^^^^

This definition, right here.
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...:oldsmile:

Sorry for the redundancies in advance...

^^^^^^^^^

This definition, right here.

Completely agree...common emitter
 

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