stachel
Newbie level 3
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hi everyone,
i'm designing a RFPA. At the input side a balun is used to convert single-ended signal to differential signal.
i have two questions:
1. i think the input impedance Zin of transistor should be conjugate matched to source impedance Zs, am i right?
2. to get Zs, i must know the output impedance of balun Ztr. i wanna make a AC-simulation and Ztr=V/I.
but when a input signal is added to PORT and a resistence R is added at the right side of balun, the simulated impedance is always equal to R (i.e. the impedance looking to right side, but what i want is the impedance looking to left side). How should i setup the testbench?
regards,
stachel
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i'm designing a RFPA. At the input side a balun is used to convert single-ended signal to differential signal.
i have two questions:
1. i think the input impedance Zin of transistor should be conjugate matched to source impedance Zs, am i right?
2. to get Zs, i must know the output impedance of balun Ztr. i wanna make a AC-simulation and Ztr=V/I.
but when a input signal is added to PORT and a resistence R is added at the right side of balun, the simulated impedance is always equal to R (i.e. the impedance looking to right side, but what i want is the impedance looking to left side). How should i setup the testbench?
regards,
stachel
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