LC filter: different result from Cadence and ADS

[rlyc]

Hello analog experts,

Below is a diagram for illustration. This is a simple LC filter with ideal components simulated using SP in Virtuoso Spectre and the smith chart tool in ADS. It should appear as open to 2GHz and short to 4GHz. The circuit and parameters are identical in both cases. Could someone help me to understand the difference in result, please? I must be doing something wrong in Cadence.

thanks, everyone.

 

[FvM]

It looks like the Spectre analysis has too few frequency steps. The few points that are plotted are probably corresponding to the ADS curves.

 

[rlyc]

you are right! i changed from automatic to log scale with 20 steps per decade, and the results matched up.

Thank you!