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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: using Eldo models in Spectre? Reply #15 - May 15^th, 2007, 4:10am The subckt definition you posted has the leading "." -- can you post your Spectre translation? I've never seen "param:" in a netlist before; I'm used to seeing the .PARAM instead.
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Pavel

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Re: using Eldo models in Spectre?
Reply #16 - May 16^th, 2007, 2:23am

Geoffrey,

I put in attachment model file as I cannot reproduce it in mail body due to its size.
Could you, please, have a glance on it.

I didn't remove "simulator-specific" part at the end of model, as you told me that Spectre is capable to filter out
unrecognized parameters.

When I try to simulate it, simulator stops with error that I exposed in one of my previous messages:
last line: bad 'subckt ENLLMM9JU' statement.

Thank you in advance.

Regards

Pavel.

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test_lib.zip

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Geoffrey_Coram

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Re: using Eldo models in Spectre?
Reply #17 - May 16^th, 2007, 7:36am

Pavel -
I think it's odd that the subckt name is the same as the model name. So, I changed it; also I think you can't use "nmos level=14" in spectre format.

32c32
< M1 d g s b ENLLMM9JU w=w/nfing l=l as=as/nfing ad=ad/nfing ps=ps/nfing pd=pd/nfing M=number*nfing
---
> M1 d g s b ENLLMM9JUmod w=w/nfing l=l as=as/nfing ad=ad/nfing ps=ps/nfing pd=pd/nfing M=number*nfing
34c34
< model ENLLMM9JU nmos level=14 version = 4.4
---
> model ENLLMM9JUmod bsim4 version = 4.4

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Pavel

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Re: using Eldo models in Spectre?
Reply #18 - May 18^th, 2007, 5:42am

Geoffrey,

I followed your suggestion. Error message is the same.
Moreover, I changed "continue line" from "+" to "\" (as it seems that last one is more credible)
and commented the 'end part' of model that contains simulator-oriented parameters.

Without any effect - parser pointed to the last line:

Bad 'subckt ... ENLLMM9JU' statement.

Is there a limit in number of characters between subckt and ends statements?

Regards

P.S. In attachemnt you could find revised model

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test_lib_001.zip

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Geoffrey_Coram Senior Fellow Offline Posts: 1999 Massachusetts, USA	Re: using Eldo models in Spectre? Reply #19 - May 18^th, 2007, 8:39am When I made the changes I posted, I was able to run a circuit in my version of Spectre (just a simple dc op pt of a single transistor).
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Pavel

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Re: using Eldo models in Spectre?
Reply #20 - May 21^st, 2007, 1:28am

Geoffrey,

I appologize for my importunity, but I still cannot resolve this problem (that's apparently not so difficult).

I tried many times ... Always the same error message - Bad subckt .... statement.
In my last version it looks realy very strange - parser gives this error message pointing to the comment line,
that is situated AFTER ends declaration!!!

What is - software bug or I missed something essential (should I check/change some options).

Regards

Pavel.

P.S. In attachment there is my last model version that discloses strange behaviour of Spectre parser.

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nmos_lib.zip

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Geoffrey_Coram

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Re: using Eldo models in Spectre?
Reply #21 - May 21^st, 2007, 4:41am

Pavel wrote on May 18^th, 2007, 5:42am:

I followed your suggestion. Error message is the same.

What version of Spectre are you running?

Quote:

Moreover, I changed "continue line" from "+" to "\" (as it seems that last one is more credible)

When I tried your latest file, the \ didn't work because you left in the comment lines "//-----------"

I also found that sometimes it's important not to start on the first line -- spice has a "tradition" of ignoring the first line, so I always start my files with a line containing only "* name of circuit" or "// name of circuit". If you have the simulator lang statement there, it's not clear to me if spectre will read it.

Can you run the attached?

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nmos_test.zip

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Pavel Senior Member Offline Posts: 174 Lausanne/Switzerland	Re: using Eldo models in Spectre? Reply #22 - May 21^st, 2007, 5:08am Geoffrey, First, thank you for assistance. I tried your attachment. The results you can see below. My Spectre version is 5.10.41.112405. Regards Pavel.
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Ken Kundert Global Moderator Offline Posts: 2386 Silicon Valley	Re: using Eldo models in Spectre? Reply #23 - May 21^st, 2007, 7:59am Remove any spaces or tabs after the backslashes.
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Pavel

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Lausanne/Switzerland

Re: using Eldo models in Spectre?
Reply #24 - May 22^nd, 2007, 12:41am

Ken

I removed spaces. Now simulator takes model. Thanks.
But simulation results are far from expecting (please see the picture).
On the graph there is Id versus Vd. As you see almost no current through NMOS.
First I tried to add type = n declaration in model (I was not sure that if type isn't specified, simulator considers it as N). The result was the same - no current.
Then, considering that model was too reduced and some essential parameters were missed, I returned to "full"
model version, where I carefully removed all spaces after backslashes.
Result - the same error message from parser Bad subckt .... statement.

So Ihave 2 questions:

1. How can I proceed further - begin with the simplest model and add line by line untill parser error message appears, or there is more skilled way to debug model?

2. This relatively poor diagnostic from Spectre parser is due to my rather old version,
or in new version the situation is the same?

Regards

Pavel.

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test_bsim4_2.jpg

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Geoffrey_Coram

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Re: using Eldo models in Spectre?
Reply #25 - May 22^nd, 2007, 4:32am

Pavel wrote on May 22^nd, 2007, 12:41am:

1. How can I proceed further - begin with the simplest model and add line by line untill parser error message appears, or there is more skilled way to debug model?

That's pretty much what I'd do; though, I'd do a "binary search" -- add half of the lines, run it; if it works, add half the remaining, if it didn't, take back half of the lines you just added.

Did you also remove all the //--- comment lines, along with the spaces? Did you try the simple model with + instead of \ ? I think the parser is more tolerant of spaces/tabs when you use + instead of /, but I'm not sure.

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iamchuck New Member Offline Posts: 1	Re: using Eldo models in Spectre? Reply #26 - Jun 12^th, 2007, 2:01pm When I run Spectre, I too have seen the 'Bad subckt' error, I found that my version of Spectre does not like multiple PARAM lines that begin with PARAM. All extra instances of the PARAM card should be replaced with a '+' sign, which will continue the initial PARAM statement I hope this helps!
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