Using OPTION SCALE for only a particuar instance in Virtuoso ADE

You can do this using the "MTS" (Multi Technology Support) mechanism in ADE XL (or the new ADE Explorer or Assembler in IC617). To do this you need to use Right Mouse over the test name to pick Simulator, and turn on the MTS checkbox there (you must be using a config for this to work), and then you can do Right Mouse->MTS Options over the test name. Having done that, you can pick things like scale for different parts of your hierarchy and set them differently.

Regards,

Andrew.

Hi Andrew,

I tried to do the MTS settings as in the attached pic below. But, somehow, the sub-circuit (here named "Comparator_ver2a") is not getting recognized:

ERROR (SFE-23): "input.scs" 87: I6 is an instance of an undefined model Comparator_ver2a

(1) Is this the proper way to set up MTS when I want to define "Comparator_ver2a" by its netlist "Comparator_ver2a.pex.netlist" (loaded as a modelFile in MTS) and use its spectre view in the main schematic (along with other symbol view sub circuits)?

(2) Also, I want to use a scale=1.0 only for the sub-circuit "Comparator_ver2a", and scale=1e-6 for the rest. Should I use the "scale" or "scalem" field in this MTS?

That won't work, because the model files would only get included inside a subckt definition netlisted by the spectre netlister, which as this is a stopping view, won't happen. I see a couple of alternative ways forward:

1. Create a wrapper layer around Comparator_ver2a. In other words, create a schematic (say called Comparator_wrapper) which instantiates Comparator_ver2a, and has the same symbol as Comparator_ver2a - simply wire through all the connections. Then in the MTS setup, you can add the  model file for Comparator_ver2a and scale=1.0 with Comparator_wrapper as the MTS block. Set the default scale in the simulation->options->analog as usual.
2. Or, modify the pex netlist to include simulator options scale=1.0 within the subckt definition for Comparator_ver2a. You might have to bracket the options statement with simulator lang=spectre and simulator lang=spice if it's in SPICE syntax. Then for whatever level of hierarchy is above the Comparator_ver2a in your schematic, add that as an MTS block and just reference the model file using the form above (without specifying the scale on the form). Set the default scale in simulation->options->analog to 1e-6.

With both of these approaches, it works (hopefully) because you're taking advantage of the fact that the subckt definitions are defined in a particular scope, rather than being globally defined.

Hopefully this will work!

Regards,

Andrew.