I'm designing an IC with MOS transistors in ADS. They have a bulk contact which must be connected to substrate to obtain realistic simulations. This is obtained by using a special element of the design kit called ptap (ntap for pMOS's). This way, every transistor needs a lot of components to be placed on the schematic, which soon becomes too crowded. So I decided to create a subcircuit. It works, I even copied the symbol of the original MOS's, but the problem is I can't change the internal values of the subcircuit (I obviously need to change the \[\left(\frac{W}{L}\right)\] ratios from the first-level schematic). I tried with File -> Design Parameters -> Parameters and I created the variables with the same name and description of the MOS; I'm able to change them in the schematic but they do not correspond to the real parameters of the MOS in the subnetwork. What should I do?
In the subnetwork set width=width or W=W and length=length or L=L etc (however the parameters are named).
See the manual section about Creating Hierarchical Designs and scroll down to the section on Creating the Subnetwork. The example shows the creation of a capacitor subnetwork where the capacitance parameter is set as C=C.
Ok, thanks. The program gets angry when e.g. I assign the value "w" to the parameter w, and it comes out with a message: "Unrecognized variable or expression for parameter", even if I had defined w through the Design Parameters. Anyway, it works, since I created a (working) parametric circuit.