Load stability circle and smith chart

[Lathas]

Why do I get so many smith charts in a single ( 4 circles starting from the centre?) graph while plotting L_stabcircle using smith chart(from the palette) in ADS? Which smith circle to choose for interpreting the stable region for output stability circle?

 

[BigBoss]

Because you have 4 frequency points.Each one will show you which output impedance makes your amplifier stable or unstable..

 

[Lathas]

To be more clear, see attached file. What do those 4 grey circles(small)+2 big circles from the center mean? which one is the real smith chart for reference in this picture?


https://obrazki.elektroda.pl/5448783900_1374812155.jpg

 

[BigBoss]

Stability Circles are outside of the Smith Chart that's why ADS used extended Smith Chart.
If a circle is outiside of the Smith Chart, there isn't any real impedance that makes your amplifier unstable.It means your amplifier unconditionally stable.
But make zoom and check other circles carefully.

 

[Lathas]

Is there any option to turn off extended smith chart and see the single chart in ADS (other than using smithchart utility)?