Hello, I created a simple inverter layout in magic and I was trying to then LVS check it with my xschem layout through netgen, but when I ran the lvs command this error occurred. It seems that netgen isn't seeing the devices that are inside the layout extracted spice files. To try and fix this I tried importing the spice list directly into magic, then I tried placing the parametrized cells my self and then I tried drawing the nmos and pmos without the p-cells. Each time I extracted the spice file by running

extract all

,

ext2spice lvs

, then

ext2spice

, I then got the same error in netgen for all three attempts. I'm wondering if anyone has had this issue before and knows how to fix it. Its possible I'm missing a simple step in running lvs.

You need to select the option in xschem to put a subcircuit wrapper around the devices. Otherwise, you are comparing a subcircuit against two transistors. You should be sure to use the syntax

lvs {_file_name1 cell_name_} {_file_name2 cell_name_}

to make sure you are comparing the same subcircuit in each file. Finally, you need to pass the name of the setup file for the PDK, otherwise netgen will not know what is a device and what is an empty subcircuit.

Okay. Thank you for the response @Tim Edwards

Next argument on the command line. Where is your open_pdks installation of sky130 PDK located? For me, it would be

lvs {_file_name1 cell_name_} {_file_name2 cell_name_} /usr/share/pdk/sky130A/libs.tech/netgen/sky130A_setup.tcl

. Followed by a 4th optional argument which is the output filename, if you don't like the generic name

comp.out

.

thank you, that fixed the error