[ADS] Error Failed to create netlist with Spice model

[Hadrien Rols]

Hello everyone,

I recently imported a Spice model of a gain block from Avago Technologies () into ADS.
I am trying to perform a DC simulation but ADS returns the following error :

(stdcmds.ael line 208, column 5)
Failed to create netlist:
Port `gnd' in the design `Pierce_lib:msa0686:schematic' is directly connected to ground.


In a desperate attempt to make it work, I tried to remove the GND symbols from the component schematic but the error was still the same.

Any input on the subject is welcome
Thank you in advance.

 

[volker@muehlhaus]

I think the problem is that a port in the Spice netlist was called "gnd" and that is a reserved name in ADS for global ground. You should be able to fix this by changing the 3-port subcircuit into a 2-port (don't forget to change the symbol as well) and just delete that port "gnd" in the subcircuit. The ground connection is already made there by placing a GND symbol and assigning netname gnd.

 

[Hadrien Rols]

Thank you ! I deleted the gnd port and connected a GND symbol to a gnd net like you said and the error is gone.




Now when I run the default DC simulation I get weird results :



The device (a MSA0686 gain block) is expected to draw approx. 16mA when Vd = 3.5V. So I put a 100 Ω resistor between the 5V Vcc and Vd.
But what I get instead is no current at all.

Here are the sub-circuits inside the model.

 

[volker@muehlhaus]

Check if there is a DC path from the inner device to gnd. Otherwise, we might have deleted that when removing the GND port.