@User I've been looking to the monte-carlo stuff a bit further and I think I've come across a better approach: In the

models/paramters/montecarlo.spice

file there are equations to create the parameters for all the devices in the PDK from a smaller set of process parameters. These parameters are more fundamental and I expect are more likely to be tracked during manufacture. Things like

hvn_mobility

or

hvn_threshold

. In the

models/parameters/critical.spice

file these values are all set to zero but the statistical values are in comments below. So I've added a

mc

section to my

sky130.lib.spice

file with the gaussian expression for these parameters (attached as file). The result being that all you need to do to start a Monte-Carlo is add this include to your netlist:

.lib sky130_fd_pr/models/sky130.lib.spice mc

. In my implementation I've set sigma to 3 but I assume you could just override this at the top level to something else if you want, ie.

.param sigma = 6

. @User if you agree this is a sensible approach I think it would be good to add this 'mc' entry to the repository so all can use this method in the future