darcyrandall2004
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how to determine generator impedance
Hello,
Recently I have been having some difficulty designing a particular stable CC amplifier. Generally I just work with the amp until it is unconditionally stable and then I just calculate the simulatenous conjugate match or determine the load that will provide a particular gain from power gain circles. I have been trying to design a CC amp from a potentially unstable transistor.
My understanding is that:
If the transistor amp is potentially unstable then plot the load stability circle. Determine a load reflection coefficient that results in an input reflection coefficient < 1 ie a stable transistor. From this load reflection coefficient calculate the corresponding load impedance. From the S parameters and load reflection coefficient, calculate the input reflection coefficient hence determine the input impedance. For maximum gain calculate the generator impedance as the conjugate of the input impedance.
Is this correct? I have been having great difficulty and I am starting to suspect I have a misunderstanding.
Thanks in advance for your help.
Hello,
Recently I have been having some difficulty designing a particular stable CC amplifier. Generally I just work with the amp until it is unconditionally stable and then I just calculate the simulatenous conjugate match or determine the load that will provide a particular gain from power gain circles. I have been trying to design a CC amp from a potentially unstable transistor.
My understanding is that:
If the transistor amp is potentially unstable then plot the load stability circle. Determine a load reflection coefficient that results in an input reflection coefficient < 1 ie a stable transistor. From this load reflection coefficient calculate the corresponding load impedance. From the S parameters and load reflection coefficient, calculate the input reflection coefficient hence determine the input impedance. For maximum gain calculate the generator impedance as the conjugate of the input impedance.
Is this correct? I have been having great difficulty and I am starting to suspect I have a misunderstanding.
Thanks in advance for your help.