HLP: how to stimulate a balun LNA with 1 input--2 outputs

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Hi, everyone! I am practicing a wideband LNA, 100MHz---2GHz

The circuit in Fig1 has two signal paths: one is M1—M3—Vo2, the other is M2—M4—Vo1. And the two paths have the same voltage gain，which is one of my design targets.

The key is I need the differential output signal so that I can cancel the noise of M1.


I have one question: This LNA has single input and different outputs. I do not know how to transform the differential outputs to single input with cadence.

Maybe I can use an ideal balun in cadence, Fig2
But the question is the two output resistors do not have the same value. One is 400Ω, and the other is 100Ω. Can I set a balun behind the two outputs?

Another question is there is an ideal balun in cadence. But I do not know its turn ratio. From Fig3, we know only the turn ratio=1: can we have ZL=Zs=Z.
Dose the ideal balun in cadence has this ratio?

I think in cadence you can use a VCVS as a ideal balun, with one of the outputs grounded. I don't think you would have to care about the impedances this way, it would be purely ideal. I think.....

Cadence also does have an ideal balun.