Common Source Aplifier - finding values of bypass capacitors

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A user is seeking assistance in designing a common source amplifier with specified voltage gains of 26 dB without a bypass capacitor and 40 dB with one, targeting a frequency range of 100-1000 Hz. They are struggling to calculate the appropriate value for the bypass capacitor and have not found helpful resources. The discussion includes a request for circuit sketches and clarification on the gains mentioned. The user also expresses a desire to learn how to use PSPICE or LTSPICE for circuit simulation. Overall, the thread focuses on amplifier design challenges and software learning.
peace_lp
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Hi,
I am new to this website. I am having troubles in designing a common source amplifier with a voltage gain, Av=26 dB (no bypass capacitor) and a gain of 40 DB (with a bypass capacitor) and a frequency of 100-1000HZ. Can anyone please guide me to calculate the value of the bypass capacitor? I searched everywhere for the methods of finding the capacitors values but still in vain. :frown: :confused:
thank you very much for all your help.

thanks,
peace
 
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Can you post a sketch of your circuit? Also, you list two different gains. What is the 40dB number representing?
 
Dear berkeman,
Thanks a lot for your reply. The 26 db is the gain when there is no bypass capacitor in the circuit while the 40 dB is the gain when there is a bypass capacitor in the circuit.
Oh by the way, do you know how to use PSPICE or LTSPICE to generate the circuit? I am so sorry for sounding like such a poor computer engineer student. I am trying to learn how to use PSPICE or LTSPICE to generate the results.
Thank you very much for your help. I really appreciate all the help given.

thanks,
peace
 
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