From b0836ebcc2d0b198582c11a2334c08d0191d2cbf Mon Sep 17 00:00:00 2001
From: PhillipRambo <phillipfbp@gmail.com>
Date: Mon, 9 Feb 2026 16:18:57 +0100
Subject: [PATCH] push inverter PEX demo

---
 utils/PEX_Demo/simulations/inverter.spice |  8 +++
 utils/PEX_Demo/xschem/inverter_tb_pex.sch | 84 +++++++++++++++++++++++
 utils/PEX_Demo/xschem/xschemrc            | 12 ++++
 3 files changed, 104 insertions(+)
 create mode 100644 utils/PEX_Demo/simulations/inverter.spice
 create mode 100644 utils/PEX_Demo/xschem/inverter_tb_pex.sch
 create mode 100644 utils/PEX_Demo/xschem/xschemrc

diff --git a/utils/PEX_Demo/simulations/inverter.spice b/utils/PEX_Demo/simulations/inverter.spice
new file mode 100644
index 00000000..93e31ee8
--- /dev/null
+++ b/utils/PEX_Demo/simulations/inverter.spice
@@ -0,0 +1,8 @@
+** sch_path: /home/pedersen/misc/inverter_example/inverter.sch
+.SUBCKT inverter Vdd Vin Vout Gnd
+*.PININFO Vout:B Vdd:B Vin:B Gnd:B
+M1 Vout Vin Gnd net2 sg13_lv_nmos w=1.0u l=0.45u ng=1 m=1
+M2 Vout Vin Vdd net1 sg13_lv_pmos w=2.0u l=0.45u ng=1 m=1
+R1 Vdd net1 ntap1 A=6.084e-13 P=3.12e-06
+R2 Gnd net2 ptap1 A=6.084e-13 P=3.12e-06
+.ENDS
diff --git a/utils/PEX_Demo/xschem/inverter_tb_pex.sch b/utils/PEX_Demo/xschem/inverter_tb_pex.sch
new file mode 100644
index 00000000..9e8395e5
--- /dev/null
+++ b/utils/PEX_Demo/xschem/inverter_tb_pex.sch
@@ -0,0 +1,84 @@
+v {xschem version=3.4.6 file_version=1.2}
+G {}
+K {}
+V {}
+S {}
+E {}
+B 2 710 -550 1510 -150 {flags=graph
+y1=-0.0023
+y2=1.3
+ypos1=0
+ypos2=2
+divy=5
+subdivy=1
+unity=1
+x1=0
+x2=2e-06
+divx=5
+subdivx=1
+xlabmag=1.0
+ylabmag=1.0
+node=vout
+color=4
+dataset=-1
+unitx=1
+logx=0
+logy=0
+}
+N 150 -170 150 -140 {lab=Vin}
+N 70 -170 70 -140 {lab=Vdd}
+N 70 -80 70 -60 {lab=GND}
+N 110 -60 150 -60 {lab=GND}
+N 150 -80 150 -60 {lab=GND}
+N 110 -60 110 -50 {lab=GND}
+N 70 -60 110 -60 {lab=GND}
+N 320 -410 320 -380 {lab=Vdd}
+N 320 -210 320 -190 {lab=GND}
+N 220 -300 240 -300 {lab=Vin}
+N 520 -300 540 -300 {lab=Vout}
+C {vsource.sym} 150 -110 0 0 {name=V1 value="PULSE(0 1.2 0.5u 10n 10n 1u 2u 1)" savecurrent=false}
+C {vsource.sym} 70 -110 0 0 {name=V2 value=1.2 savecurrent=false}
+C {gnd.sym} 110 -50 0 0 {name=l2 lab=GND}
+C {lab_pin.sym} 150 -170 0 0 {name=p1 sig_type=std_logic lab=Vin}
+C {lab_pin.sym} 70 -170 0 0 {name=p3 sig_type=std_logic lab=Vdd}
+C {code_shown.sym} 40 -660 0 0 {name=NGSPICE
+only_toplevel=true
+value="
+.control
+save all
+tran 50n 2u 
+write test_inverter.raw
+.endc
+" }
+C {devices/code_shown.sym} 280 -540 0 0 {name=MODEL only_toplevel=true
+format="tcleval( @value )"
+value="
+.lib cornerMOSlv.lib mos_tt
+.lib cornerRES.lib res_typ
+
+"}
+C {launcher.sym} 770 -120 0 0 {name=h5
+descr="load waves" 
+tclcommand="xschem raw_read $netlist_dir/test_inverter.raw tran"
+}
+C {inverter.sym} 390 -300 0 0 {
+name=x1
+schematic=inverter_pex
+spice_sym_def="
+.subckt inverter_pex Vdd Vin Vout Gnd
+X0 Vout Vin Vdd Vdd sg13_lv_pmos ad=0.68p pd=4.68u as=0.68p ps=4.68u w=2u l=0.45u
+X1 Vout Vin Gnd Gnd sg13_lv_nmos ad=0.34p pd=2.68u as=0.34p ps=2.68u w=1u l=0.45u
+C0 Vout Vin 0.10077f
+C1 Vin Vdd 0.14482f
+C2 Vout Vdd 0.13155f
+R0 Vin Vin.n0 7.52248
+C3 Vout Gnd 0.39245f
+C4 Vin Gnd 0.64666f
+C5 Vdd Gnd 0.15308f
+.ends
+"
+}
+C {lab_pin.sym} 220 -300 0 0 {name=p2 sig_type=std_logic lab=Vin}
+C {gnd.sym} 320 -190 0 0 {name=l1 lab=GND}
+C {lab_pin.sym} 320 -410 0 0 {name=p4 sig_type=std_logic lab=Vdd}
+C {lab_pin.sym} 540 -300 0 1 {name=p5 sig_type=std_logic lab=Vout}
diff --git a/utils/PEX_Demo/xschem/xschemrc b/utils/PEX_Demo/xschem/xschemrc
new file mode 100644
index 00000000..890298f1
--- /dev/null
+++ b/utils/PEX_Demo/xschem/xschemrc
@@ -0,0 +1,12 @@
+# xschemrc - Custom configuration file for xschem
+# This file sources another xschemrc file from a known location
+
+# Source the base configuration from a known location
+source $::env(PDK_ROOT)/$::env(PDK)/libs.tech/xschem/xschemrc
+
+# (Optional) Add any custom overrides or extensions below
+# set xschem_library_path /home/user/my_libs
+# set xschem_gui_font "Monospace 10"
+
+append XSCHEM_LIBRARY_PATH :$PDK_ROOT/ihp-sg13g2/libs.tech/xschem
+append XSCHEM_LIBRARY_PATH :../