How to save different checklimitfile for multiple parallel runs in Device Checking?

Two suggestions:

1. If you give a path for the checklimitfile which isn't a full path (i.e. has no "/" in the path), then it will be saved as a file in the netlist directory (I think) in each point. Or you could save it as "../psf/checklimit.txt" and it would be in the psf dir for each point. Then they won't overlap
2. Or you could use the capability introduced in IC617/ICADV122 to view the checks/asserts view of the results after the run. The results are saved in an SQL database and you can then set up queries across the results. There's a Rapid Adoption Kit on this on support.cadence.com - Check & Assertions (there's also a newer one for Assembler too: Checks & Assertions flow in ADE)

Andrew

Thanks Andrew. Relative path works as you mentioned.

I have looked at the Customize Violation filter. It looks very useful.

One question slightly related to that: I want to know peak value of violation during violation window. Both checklimit file and ADEXL GUI don't report peak value. I tried to attach the ADEXL picture below. For instance, it shows Vgs voltage in message but peakvalue is missing, but I know that that Vgs goes to all the way 1.2V during that violation window, which I don't see from Checks/Asserts results

Also, below is the checklimit file output for that which doesn't have any violating voltage level

Warning from spectre at time = 17.6696 ps during transient analysis `tran'.
    WARNING (SPECTRE-4056): assert_pch_ulvt_vgs, Instance X0.MP0: PMOS Vgs
        voltage exceeded beyond +/-1.05V. Expression `abs(V(g,s))>1.05' is
        getting true.
    WARNING (SPECTRE-4056): assert_nch_ulvt_vgs, Instance X0.MN0: NMOS Vgs
        voltage exceeded beyond +/-1.05V. Expression `abs(V(g,s))>1.05' is
        getting true.
Warning from spectre at time = 18.9306 ps during transient analysis `tran'.
    WARNING (SPECTRE-4056): assert_pch_ulvt_vgd, Instance X0.MP0: PMOS Vgd
        voltage exceeded beyond +/-1.05V. Expression `abs(V(g,d))>1.05' is
        getting true.
    WARNING (SPECTRE-4056): assert_nch_ulvt_vgd, Instance X0.MN0: NMOS Vgd
        voltage exceeded beyond +/-1.05V. Expression `abs(V(g,d))>1.05' is
        getting true.

I have searched support cadence and found "checklimit_full_duration=yes" option but it seems that it doesn't change what is reported after simulation ends. That may be version issue I am using.

Andrew, is there a way to report max violation voltage as well?

Thanks

yayla

This is transient waveform for the above data

Maybe this will help: https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1Od0000000vh9VEAQ

The issue is because of how the assert is formulated. It's formulated as a boolean expression (like the second below) and so there's no "peak" because the expression is either 1 or 0. If it was implemented like either of the first or the third, then you get a peak shown:

//

assert_nch_1 assert mod=gpdk090_nmos1v param=vgs max=0.8
assert_nch_2 assert mod=gpdk090_nmos1v expr="V(g,s)>0.8"
assert_nch_3 assert mod=gpdk090_nmos1v expr="abs(V(g,s))" max=0.8

Here's what the checks and assert view looks like:

Regards,

Andrew.

Thanks Frank and Andrew for the replies.

Frank, I will try the margin setting.

Andrew, below are my assert statements which I believe are similar to 2nd except abs(). Is using abs() causing an issue?

// Core ulvt voltage assertions
assert_pch_ulvt_vgs assert mod=pch_ulvt expr="abs(V(g,s))>1.05" check_windows=[tstart_assert tend_assert] duration=tduration_assert message="PMOS Vgs voltage exceeded beyond +/-1.05V"
assert_pch_ulvt_vgd assert mod=pch_ulvt expr="abs(V(g,d))>1.05" check_windows=[tstart_assert tend_assert] duration=tduration_assert message="PMOS Vgd voltage exceeded beyond +/-1.05V"

Thanks

yayla

Hi Yayla,

Just noticed a mistake in my previous post (I got the order wrong - the first and the third show a peak, the second doesn't) - I've corrected the post. 

Anyway, the issue is not with the abs() (maybe my typo had confused things as I got the order wrong). The issue is that you have  an expression with >1.05. This means that the expression is a boolean expression and thus returns 1 or 0. If you use:

// Core ulvt voltage assertions
assert_pch_ulvt_vgs assert mod=pch_ulvt expr="abs(V(g,s))" max=1.05 check_windows=[tstart_assert tend_assert] duration=tduration_assert message="PMOS Vgs voltage exceeded beyond +/-1.05V"
assert_pch_ulvt_vgd assert mod=pch_ulvt expr="abs(V(g,d))" max=1.05 check_windows=[tstart_assert tend_assert] duration=tduration_assert message="PMOS Vgd voltage exceeded beyond +/-1.05V"

Then it should give you the peak, as the expression is then the voltage (or the absolute voltage).

Regards,

Andrew.

Thanks Andrew. I have changed the rules and everything works now. And I got it what you mean by "boolean expression" .

Thanks,

yayla