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<@U016EM8L91B> - this file extracts to a 0.25 length mosfet, but the gate length is actually 0.15. M...
# magic
m
@Tim Edwards - this file extracts to a 0.25 length mosfet, but the gate length is actually 0.15. Magic 8.3.331 extracts at 0.15, but Magic 8.3.413 extracts as 0.25.
t
The gate length in my view is 0.24um, and I get a corresponding extraction:
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X0 drain gate source VSUBS sky130_fd_pr__nfet_01v8 ad=0.2405 pd=2.04 as=0.221 ps=1.98 w=0.65 l=0.24
No version of magic should extract this as either 0.15 or 0.25. How are you coming up with the "actual" measurement of 0.15?
My suspicion is that the issue is that you are not consistently using 
ext2spice
options, and what you are seeing is values for W and L that are not in microns, but which correspond to a 
.option scale=
parameter at the top of the netlist that defines the relationship between listed dimensions and SI units. If you always use 
ext2spice lvs
, that sets up a bunch of options including not scaling the values (other than that for SkyWater, the models have an implicit scale of 1e-6, so the units are microns, not meters).
m
Thanks Tim, I'll double check
The measurement came from selecting the gate and then typing box to get the dimensions
t
That's not what I see, though.
This is what you posted and what it looks like when I load it into magic:
m
ok, I'm confused, I probably didn't do ext2spice lvs and extracted the wrong dimensions
the box measurement I get is the same as yours
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