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Parameterizing variable which uses calcVal throws Error

aviquid

Hi,

So I have a test named "calibrate" which is used to calculate a certain variable "vdiff" (just think of it as an offset). I then use this variable "vdiff" in another test called "opr1" where I want to sweep another variable cap_bias_diff from "-vdiff" to "+vdiff" in steps of 0.1V.

So, in "opr1" test, I want to sweep cap_bias_diff = -1*calcVal("Vdiff_final" "calibrate"):0.1:calcVal("Vdiff_final" "calibrate")

However, I see the error that parameter cap_bias_diff is not a valid range (attached screenshot below). Please do help. Thanks.

Parents

  • Using calcVal or other expressions that refer to other variables in sweep ranges is not supported. To be honest it would get horribly complicated and the number of sweep points would be pretty irregular (potentially) and it could be pretty hard to represent the results clearly (that’s only one of the challenges it would represent). Of course, you could have a uniform sweep that sweeps from (say) 0 to 1 in 0.1 steps and then use that sweep variable plus the calcVal in another variable’s expression - not quite all the freedom you want, but maybe a compromise that’s good enough?

  • in reply to Andrew Beckett

    Hi Andrew,

    I just gave an example of sweeping from -vdiff to + vdiff. Ideally, I want to sweep from vdiff-20m:1m:vdiff+20m, so 41 uniform steps in total for all corners.

    This aside, is there any way that I can accomplish this, either by using ocean scripting? Please advise. Thanks

  • in reply to aviquid

    I'd misread your original post - I'd thought you had a different calcVal at each end of the sweep. Because you don't, the approach I suggested will work - in other words, define two variables:

    sweep_offset => -20m:1m:20m
    sweep_var => sweep_offset+calcVal("Vdiff_final" "calibrate")

    This will achieve what you want.

    Andrew

  • in reply to Andrew Beckett

    Hi Andrew,

    This approach works. Just that I had to make this small alteration to the sweep_var => sweep_offset+calcVal("Vdiff_final" "calibrate" ?matchParams list(list("sweep_offset" 0))) . In "calibration" test, sweep_offset has no role to play, but it does have a role in the "opr" test. Hence, had to add this to matchParams for both the tests. Worked like a charm Slight smile

    But yes, thank you for this. Appreciate your help.

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  • in reply to Andrew Beckett

    Hi Andrew,

    This approach works. Just that I had to make this small alteration to the sweep_var => sweep_offset+calcVal("Vdiff_final" "calibrate" ?matchParams list(list("sweep_offset" 0))) . In "calibration" test, sweep_offset has no role to play, but it does have a role in the "opr" test. Hence, had to add this to matchParams for both the tests. Worked like a charm Slight smile

    But yes, thank you for this. Appreciate your help.

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