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#analog-design
Title
# analog-design
y

Yueting Li

03/31/2022, 1:59 AM
I am trying to do a monte carlo simulation so I select the corner mc, while I find sky130_fd_pr__pnp_05v5_W3p40L3p40 can not be included this way. Below is my super simple testing codes:
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*Title: test mc include sky130_fd_pr__pnp_05v5_W3p40L3p40 or not
.lib " OPEN_PDKS_PATH/sky130A/libs.tech/ngspice/sky130.lib.spice" mc
XQ1 GND GND vbneg sky130_fd_pr__pnp_05v5_W3p40L3p40 m=39
I got error like this:
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Circuit: *title: test mc include sky130_fd_pr__pnp_05v5_w3p40l3p40 or not

Error: unknown subckt: xq1 0 0 vbneg sky130_fd_pr__pnp_05v5_w3p40l3p40 m=39
    Simulation interrupted due to error!

Error: there aren't any circuits loaded.
Does anyone has suggestions towards which corner (tt/ff/...) to choose and how to set parameter mc_mm_switch/mc_pr_switch when doing monte carlo simulations.
t

Tim Edwards

03/31/2022, 12:21 PM
Yet another error in the SkyWater sources. The
sky130.lib.spice
includes
parameters/montecarlo.spice
which includes all of the model files, including the NPNs, but is missing the PNPs. Just add the include lines for the PNPs in
montecarlo.spice
. I will write a script in the open_pdks installer to correct it.
I am concerned, though, that the monte carlo parameters are not defined for the PNP devices. In the same file there are parameters set for the NPN, but not for the PNP.
y

Yueting Li

03/31/2022, 10:33 PM
Thanks you for fixing that. Does that indicate monte carlo simulations couldn't be run for the PNP by any means?
t

Tim Edwards

04/01/2022, 12:25 AM
I haven't had time to figure that out. The values might be in a file somewhere that's being ignored, or the values might be able to be pulled from the e-test data tables.
y

Yueting Li

04/01/2022, 12:53 AM
Ok, I'd run a test on that and let you know if any updates about that.
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