Can anyone let me know what can be the reason for the below issue, I downloaded the schematic from somewhere.

The schematic probably has hardwired absolute path in it.

How to change the path?

I usually open it with a text editor and use the replace function to fix them all at once ...

You mean .sch file ?

yes

v {xschem version=3.4.5 file_version=1.2

}

G {}

K {}

V {}

S {}

E {}

N -900 -490 -880 -490 {

lab=#net1}

N -900 -490 -900 -360 {

lab=#net1}

N -840 -460 -840 -440 {

lab=#net1}

N -900 -440 -840 -440 {

lab=#net1}

N -800 -340 -770 -340 {

lab=vinn}

N -840 -550 -840 -520 {

lab=vdd}

N -840 -550 -200 -550 {

lab=vdd}

N -200 -550 -200 -520 {

lab=vdd}

N -840 -490 -680 -490 {

lab=vdd}

N -640 -550 -640 -520 {

lab=vdd}

N -640 -520 -640 -490 {

lab=vdd}

N -840 -520 -840 -490 {

lab=vdd}

N -640 -490 -400 -490 {

lab=vdd}

N -360 -550 -360 -520 {

lab=vdd}

N -360 -520 -360 -490 {

lab=vdd}

N -360 -490 -240 -490 {

lab=vdd}

N -200 -520 -200 -490 {

lab=vdd}

N -730 -390 -730 -370 {

lab=#net2}

N -730 -390 -530 -390 {

lab=#net2}

N -530 -390 -530 -370 {

lab=#net2}

N -640 -460 -640 -390 {

lab=#net2}

N -730 -310 -730 -250 {

lab=#net3}

N -690 -220 -570 -220 {

lab=#net3}

N -730 -280 -680 -280 {

lab=#net3}

N -680 -280 -680 -220 {

lab=#net3}

N -730 -190 -730 -160 {

lab=vss}

N -730 -160 -530 -160 {

lab=vss}

N -530 -190 -530 -160 {

lab=vss}

N -530 -310 -530 -250 {

lab=#net4}

N -730 -220 -730 -190 {

lab=vss}

N -530 -220 -530 -190 {

lab=vss}

N -530 -280 -400 -280 {

lab=#net4}

N -360 -460 -360 -310 {

lab=#net5}

N -360 -280 -360 -250 {

lab=vss}

N -360 -250 -360 -160 {

lab=vss}

N -530 -160 -360 -160 {

lab=vss}

N -360 -340 -240 -340 {

lab=#net5}

N -200 -460 -200 -370 {

lab=vout}

N -200 -370 -200 -340 {

lab=vout}

N -200 -310 -200 -160 {

lab=vss}

N -360 -160 -200 -160 {

lab=vss}

N -900 -300 -900 -160 {

lab=vss}

N -900 -160 -730 -160 {

lab=vss}

N -930 -160 -900 -160 {

lab=vss}

N -930 -550 -840 -550 {

lab=vdd}

N -610 -340 -570 -340 {

lab=vinp}

N -380 -340 -360 -340 {

lab=#net5}

N -440 -340 -440 -280 {

lab=#net4}

N -530 -370 -530 -340 {

lab=#net2}

N -730 -370 -730 -340 {

lab=#net2}

N -200 -410 -180 -410 {

lab=vout}

C {sky130_fd_pr/pfet_01v8.sym} -750 -340 0 0 {name=M1

W=1.08u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

l}

C {sky130_fd_pr/pfet_01v8.sym} -550 -340 0 0 {name=M2

W=1.08u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/nfet_01v8.sym} -710 -220 0 1 {name=M3

W=0.36u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=nfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/nfet_01v8.sym} -550 -220 0 0 {name=M4

W=0.36u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=nfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/pfet_01v8.sym} -660 -490 0 0 {name=M5

W=4.5432u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/nfet_01v8.sym} -380 -280 0 0 {name=M6

W=1.08u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=nfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/pfet_01v8.sym} -380 -490 0 0 {name=M7

W=6.5412u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/pfet_01v8.sym} -220 -340 0 0 {name=M8

W=12.4848u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/pfet_01v8.sym} -220 -490 0 0 {name=M9

W=27.27u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

}

C {sky130_fd_pr/pfet_01v8.sym} -860 -490 0 0 {name=M10

W=27.27u

L=0.36u

nf=1

mult=1

ad="'int((nf+1)/2) * W/nf * 0.29'"

pd="'2*int((nf+1)/2) * (W/nf + 0.29)'"

as="'int((nf+2)/2) * W/nf * 0.29'"

ps="'2*int((nf+2)/2) * (W/nf + 0.29)'"

nrd="'0.29 / W'" nrs="'0.29 / W'"

sa=0 sb=0 sd=0

model=pfet_01v8

spiceprefix=X

}

C {res.sym} -900 -330 0 0 {name=R1

value=34k

footprint=1206

device=resistor

m=1}

C {capa.sym} -410 -340 1 0 {name=C1

m=1

value=0.1p

footprint=1206

device="ceramic capacitor"}

C {lab_pin.sym} -930 -550 0 0 {name=p1 sig_type=std_logic lab=vdd}

C {lab_pin.sym} -930 -160 0 0 {name=p2 sig_type=std_logic lab=vss}

C {lab_pin.sym} -800 -340 0 0 {name=p3 sig_type=std_logic lab=vinn}

C {lab_pin.sym} -610 -340 0 0 {name=p4 sig_type=std_logic lab=vinp}

C {lab_pin.sym} -180 -410 2 0 {name=p5 sig_type=std_logic lab=vout}

C {ipin.sym} -1090 -520 0 0 {name=p6 lab=vdd}

C {ipin.sym} -1090 -480 0 0 {name=p7 lab=vss}

C {ipin.sym} -1090 -440 0 0 {name=p8 lab=vinn

}

C {ipin.sym} -1090 -410 0 0 {name=p9 lab=vinp

}

C {opin.sym} -1140 -370 0 0 {name=p10 lab=vout}

Ah no, nm, it's not the issue.

@Sudeep Gopavaram @tnt 2 solutions (use one or the other, not both) 1. add this line at the end of your xschemrc file

append XSCHEM_LIBRARY_PATH :${XSCHEM_SHAREDIR}/xschem_library/devices

then start xschem and open the schematic. 2. in the xschem terminal do this command after loading the schematic with the missing symbols:

fix_symbols 1

then save the schematic.

The latest xschemrc already contains this path: https://github.com/StefanSchippers/xschem_sky130/blob/cdb5dba83695057cbf2da63b6c41a2570d68d4af/xschemrc#L31 It was added so that schematics created with the sky130 PDK use the same references to the standard symbols as when you create a schematic without the PDK loaded. This means that you can, for example, open testbenches that do not contain PDK-specific devices with a standard xschem setup and still see all the standard symbols. @Sudeep Gopavaram If you can, you should update your PDK and the problem will resolve itself.

@Leo Moser even though the method given by stefan worked out but I want to know how can I update my pdk, do I need to install it from scratch or is there some other workaround?

It depends on how you have installed the PDK. Did you install it via open_pdks? Then you need to build it from scratch. I like to use volare (https://github.com/efabless/volare) as it simply downloads pre-built versions of the PDK.