Derek Hines-Mohrman

01/23/2022, 12:31 AM
Hi all, I am relatively new to Magic, I have a question about extraction for LVS. My goal is to compare my manually layed-out cell against an original spice netlist. My cell has 5 n-fets of various sizes. 4 of the n-fets are in sub-cells of their own. However, in the extracted netlist, none of the body ports of the fets are connected to GND. Each body port, is instead connected to a net VSUBS which does not even appear to be a global variable. I ran these commands in magic to extract the spice netlist:
extract all
ext2spice lvs
ext2spice -o lvs_n-leg.spice
This extracted netlist does not match the original netlist (comparison done with netgen) because in the original netlist, all the fet bodies are connected to GND. Let me know if you have any tips to resolve this. Below is a picture of my cell, in case you can notice something obviously wrong!