errors "undefined model" when doing analog simulaton

Dear all,
When I built a simple inverter using nmos4 and pmos4 from
device_lib, and did analog simulation in ADE. It reported
"Error found by spectre in 'inv', during circuit read_in
input.scs: M0 is an instance of an undefined model en3.
input.scs: M1 is an instance of an undefined model ep3.
"
I did not know why this happend, and although I changed library to
analogLib, it still reported similar errors.

Can someone help me solve this problem?

Thank you very much!

Renee

 

renee wrote, on 06/23/08 11:27:

This will happen because the model files have not been defined.

In ADE, if you go to Setup->Model Libraries you need to define the path
to the model files, and the section they come from (if needed).

Just using the symbols is not enough (although most PDKs these days tend
to initialize the default model libraries for ADE within their
SKILL libInit.il file for the device libraries).

analogLib is not tied to any technology, so would not be expected
to initialize any model files.

Regards,

Andrew.

 

When I add /home/caddisk/cadence/cds/tools/dfII/samples/artist/models/
spectre/definitions.scs to the model library file, it said that the
item already exits in the model library. Then, I run simulation, it
still reported the same errors.

You said "Just using the symbols is not enough ", but when I drew the
schematic view, I can only use symbols, right?

Then, how can I solve this problem?

Thank you very much for your help!

Renee

 

Dear renee,

The nmos4/pmos4 from your device_lib is something related to your
foundry, Am I right ?
In this case, you need to include the model file
(yourPdkModelFile.scs) as explained earlier by Andrew.
The analogLib is just an ideal library. Please check also whether your
PDK handles a special menu/form to load the corners if not done
through the libInit.il. The PDK documentation would be very helpful
for you I think.

Usually, I'm displaying my final netlist with ADE-> Simulation ->
Netlist-> recreate and then ADE-> Simulation -> Netlist->Display, just
to ensure all my include files/sections are there. It's handy to debug
if you don't fear the ASCII files.

Good luck,

Riad.