biolycans
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Hi all,
I upload a file. In this word there are figure related to my questions.
If I have a common source amplifier (figure 1), If I want to amplify a signal vgs, this signal should be greater than Vth for the conduction of the MOSFET, for that reason I use a constant value VGS for the polarization of the mosfet.
But for example if I have a differential amplifier like in figure 2, then I don´t need a constant voltage in the gate of M1 and M2, because if the voltage between gate and source is bigger than Vth, I can put a value for example negative in the gate of M1 or M2 so if the source has a potential smaller than the negative voltage in the gate, I will have a conduction in the mosfet. Am I correct ?
Regards,
JoaquinView attachment Questions.doc
I upload a file. In this word there are figure related to my questions.
If I have a common source amplifier (figure 1), If I want to amplify a signal vgs, this signal should be greater than Vth for the conduction of the MOSFET, for that reason I use a constant value VGS for the polarization of the mosfet.
But for example if I have a differential amplifier like in figure 2, then I don´t need a constant voltage in the gate of M1 and M2, because if the voltage between gate and source is bigger than Vth, I can put a value for example negative in the gate of M1 or M2 so if the source has a potential smaller than the negative voltage in the gate, I will have a conduction in the mosfet. Am I correct ?
Regards,
JoaquinView attachment Questions.doc