Re: [Qucs-help] Verilog-A model parameters

[Guilherme B. T. <gui...@gm...>]

On 9/4/14, 3:17 PM, Anurag Mangla wrote:
> Hello,
>
> I am using the components from the Verilog-A library provided in Qucs. I
> understand that to change the parameter values one need to edit the
> properties.
> However, I do not yet understand how can I reuse a component with these
> modified parameter values. I am wondering if there is a way to save a
> component (say NMOSFET) with user supplied parameter values into the
> library? Or else, is there a way to load the parameter values from an
> external file?
>
> Thank you for your help.
>
> Best Regards,
> Anurag
> ​ Mangla​
>

Hi Anurag,

Yes you can change the properties on the GUI or hack around the netlist 
(not recomended).

To reuse the parameters I typically use sub-circuits and libraries.
Two options I can think of:

1) Create a sub-circuit
- insert component
- adjust parameters
- add ports and connect  device (G D S B)
   - at this point it is already reusable, you can pick and place it 
with a default symbol, and your parameters.


1.1) Optional:
Create a symbol. You can create a symbol and let it also be 
parameterized, you can expose just a few parameters.

This thread might help:
https://sourceforge.net/p/qucs/mailman/message/32717952/


2) Create libraries of sub-circuits (buggy at the moment)

With the created sub-circuits
- Project > create library
- Select sub-circuits found on the project dir
- Name the lib
- document if want
- Next...
- Create

Now comes the bug #1. The library managers expects the library to be in 
~/.qucs/user_libs

If you did not change the Qucs Home, you should be fine, otherwise you 
need to copy your lib to that location.

And bug #2. It might be necessary to restart qucs for it to load the 
created lib.

And bug #3. You will need to open the library manager to copy and paste 
to place it.
Even after the docked library manager finds the libs, if you pick and 
place it drops a box, not a component...

I will take care of filing these bugs out for you. :)

For your last question, loading from external file is not yet supported 
(not that I know of). We are working to enable loading model cards with 
parameters, similar to what you can find on the SPICE .model statement.

Regards,
Guilherme