Hi, I I tried layout opamp and failed on lvs. Perhaps the problem occurred because the number of transistors did not match with using the nf parameter. Is there any netgen option for this?

opamp.sp

: pre-layout file

opamp.spice

: post-layout file

@Minsang Yu A couple things to be aware of. 1. How do you run netgen? Are you using the correct setup file from the pdk that will combine parallel devices?

$PDK_ROOT/$PDK/libs.tech/netgen/${PDK}_setup.tcl

2. The

nf

parameter is ignored during LVS. Don’t confuse the

m

parameter with the

nf

parameter.

I didn't use setup file 😞. So I just rerun lvs with setupfile and thanks to your help, it seems like finger problem is solved. However, lvs pass still failed, so I think I will have to re-layout.

When you create your netlist from xschem, be sure to select

Simulation -> LVS netlist: Top level is a .subckt

When you extract the layout, try

extract no all
extract do aliases
extract do local
extract unique
extract

ext2spice lvs

I still try to do this and it seems almost done. However I have

property

and

unresolved expressions

error. Do you have any idea about it?

@Minsang Yu For LVS, the include lib files are not needed and cause the property problems you see if included.. Also, be sure to use the setup file

netgen -batch lvs "opamp.sp opamp" "opamp.spice opamp" $PDK_ROOT/$PDK/libs.tech/netgen/${PDK}_setup.tcl

Thanks for your help