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Design >> RF Design >> NF simulation using port as input(cadence spectre)
https://designers-guide.org/forum/YaBB.pl?num=1194100638

Message started by Julian18 on Nov 3^rd, 2007, 7:37am

Title: NF simulation using port as input(cadence spectre)
Post by Julian18 on Nov 3^rd, 2007, 7:37am

Hi, there
I am simulating the NF of a differential LNA, and i found the setup confused me much. I use port as my input source,connect in parallel a resistor with this port and assign to this resistor the same resistance value as that of the port resistance(i made this parallel resistor noiseless), under this set up I can get a NF curve. Of course if I drop the resistor in parallel with the port, I got a different curve. surely there is only one true curve. so which setup should I take to get the right value?

B.R.

Julian

Title: Re: NF simulation using port as input(cadence spec
Post by Ken Kundert on Nov 3^rd, 2007, 5:31pm

Is the resistor part of your circuit? If so, it should be there. If not, it should not.

-Ken