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and_extracted_magic.spice.txt

hi <@U016EM8L91B> , need some help in understanding whats going wrong in post layout sim. I have a simple AND designed and extracted from magic using command : extract all ; ext2spice lvs ; ext2spice cthresh 0 ; ext2spice rthresh 0 ; ext2spice

LVS is clean , simulation with xschem is fine , DRC clean, But when i do Post lay sim , there is degradation is output voltages.

What could be reasons ? Any hints we can get from the extracted spice netlist ?

At a glance, your netlist looks okay.  What does the testbench circuit look like?

<@U016EM8L91B> , its simple pulses :

** sch_path: /home/ratul619/IIT_study_VM/xschem/sim_AND_g5D10_W0p840_L0p5_10_7.sch
**.subckt sim_AND_g5D10_W0p840_L0p5_10_7
x1 VDD GND IN0 IN1 OUT AND_g5D10_W0p840_L0p5_10_7
V1 VDD GND 3.3
V2 IN1 GND PULSE 3.3 0 0.1ns 0.1ns 0.1ns 30ns 60ns
V3 IN0 GND PULSE 3.3 0 0.1ns 0.1ns 0.1ns 20ns 40ns
**.ends
.GLOBAL GND


.include /home/ratul619/IIT_study_VM/magic/sky130_layouts/and_D1_W0p840_L0p5_10_7.post_sim.spice

.tran 0.01n 100n
.save all


.lib /home/ratul619/IIT_study_VM/OpenLane/pdks/sky130B/libs.tech/ngspice/sky130.lib.spice tt




.end

post_sim.spice.txt

Hi <@U016EM8L91B> , getting error in ngspice reading the extracted netlist with below commands :

```extract do local
extract all
ext2sim labels on
ext2sim
extresist tolerance 10
extresist
ext2spice lvs
ext2spice cthresh 0
ext2spice extresist on
ext2spice```
ngspice error :

Error on line 0 or its substitute:
  m.x1.x0.msky130_fd_pr__pfet_g5v0d10v5 x1.decoder_d1_g5d10_10_07_0/in1_inv x1.in1.t5 out out x1.x0:sky130_fd_pr__pfet_g5v0d10v5__model l=   0.000000000000000e+00    w=   0.000000000000000e+00    nf=   1.000000000000000e+00    ad=   2.436000000000000e-01    as=   4.384800000000000e+00    pd=   2.260000000000000e+00    ps=   4.068000000000000e+01    nrd=   0.000000000000000e+00    nrs=   0.000000000000000e+00    sa=   0.000000000000000e+00    sb=   0.000000000000000e+00    sd=   0.000000000000000e+00
could not find a valid modelname
    Simulation interrupted due to error!

What are the correct set of commands for extracting the netlist from magic ? I tried multiple options , nothing seems to work

That's the correct extraction, but magic has a difficult time doing full RC extraction with hierarchy.  So the best approach is to do `flatten &lt;cellname&gt;` followed by `load &lt;cellname&gt;` and then do all the rest of the commands you showed above.