Hello,
We have a layout with layout cells for inductors and capacitors to impedance match a Qorvo LNA (they provde an S2P).
Each capacitor/inductor S2P file from muRata straddles each layout cell so we can see how EM coupling affects the match.
We would like to get the combined behavior of EM+S2P. The extraction shows ports at each component location where the iNets connect.
When we used AXIEM to simulate the EM, it seems to only simulate the metal, but ignores the S2P components that are connected to on the circuit schematic.
Is there a way to get AXIEM (or another EM simulator) to use the S2P components at the same time that EM simulation takes place so we can see how layout coupling affects the impedance match?
Please see the attached .emz archive:
Uh, oh. It is bigger than 1MB. Here are some pictures, maybe you can help!
- The schematic "LNA test" is where the extraction takes takes place, and the graphs and measurements reference this schematic as well.
- The schematic "LNA 144MHz Component" schematic has the LNA layout. (Note that subcircuits like "S2P_CAP_0402" combine the footprint with S2P connectivity so we can switch between EM and not-EM by toggling the EXTRACT block. The layout cell footprints (like 0402) are applied to dummy components inside the S2P_CAP_0402 subcircuit to help with that.)
- The extraction "EM_Extract_Doc" shows the extraction and ports at every component pad.
- The graph "LNA" shows S11 and S21:
- With the EXTRACT block in the "LNA test" schematic disabled, the graph shows a good S11/21.
- With the EXTRACT block enabled, S11/21 are horrible, presumably because AXIEM is not considering the S2P components and only simulates metal. See the "Show Currents" output, all current is on the Port 1 MLIN, nothing gets past, everything reflects.
- (press F8, EM takes ~1 minute to simulate)
See this video we made about this project for ideal optimization, what we are trying to do now is simulate a circuit board with real components to have it made:
https://www.youtube.com/watch?v=cMte9q1hoHM
Also, is there a way to "show currents" in the 2D extraction view?
Schematic:
Layout:
Extraction:
-Zeke & Eric