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does any one have of tutorial kind of thing to inc...
# magic
a
does any one have of tutorial kind of thing to include the tech file and draw a layout for basic inverter using sky130.
k
@Nickson Jose @Praharsha
n
Hi @Ashok Kumar. You might want to check the "Standard cell layout design in Magic" section of the below repo
a
Thank you I'll go through it
m
That has a makefile that shows the paths and arguments needed to get magic loaded with the tech file.
There is a video too
a
i actually loaded the .tech file using the command "magic -T sky130A.tech &"
and it opened but there is only access to limited layers. some of them are locked
this was the window when i opened the magic tool with the above command.
n
You can unlock the remaining layers by clicking Layers --> Unlock base layers . Also would recommend referring the below website for any info related to Magic Layout tool. http://opencircuitdesign.com/magic/
a
thank you @Nickson Jose @Matt Venn it worked.
r

https://youtu.be/IQ_DcWT_cbc▾

a
@Matt Venn i did exactly as said in the video but i came across an error while extracting saying "Device nmos does not have a compatible substrate node!"
Screenshot (1513).png
n
@Ashok Kumar.can you select the section of poly over ndiff (by pressing 
s
) and type 
what
on tkcon window to first verify whether nmos is being identified by magic or not?
a
yes it is showing nmos
as the selected mask layers
@Nickson Jose
n
Not very sure what could be the exact cause. Which version of Magic tool are you working on?
You can type 
magic --version
in the Unix shell to find out the version.
a
magic 8.2
n
Can you try upgrading the tool to 8.3.60 or any later version and try again? Maybe @Tim Edwards or @Matt Venn can later point out what exactly could be the issue.
a
thank you .i'll do that.
👍 1
thanks @Nickson Jose it worked and when i extracted your inverter into spice code i have observed the w and l vaues are very high.
can we change them in the spice simualtions using .option scale
n
Yeah you can
a
Ok thank you. It's working 🙂
🙌 1
@Matt Venn in your youtube video your extracted spice file has the model names sky130_fd_pr_nfet. when i tried in your way i got them as "nshort". have you wrote them manually ??
m
No that's how it came out for me
Do you see how in starting magic with the RC file?
r
no, 'n-short' means it detected your drawing as a wire short
m
Ah so a mistake in the drawing
a
i have used the command as 'magic -T sky130A.tech inverter.mag'. is this wrong?
n
@Riking28 you sure n-short indicates a wire short? I think it is alias for nfet in magic
r
No, I'm not sure :)
d
nshort is alias for nfet i think
@Nickson Jose can we get sky130A.tech from sky130 github or is it ok to take it form your github lib folder?
n
@Deepak both are same. I had actually uploaded the tech file in my repo from sky130 project only.
d
okay
a
@Nickson Jose I want my spice file to consist of specific model name instead of nshort. Can I do that in magic ?
@Deepak alias is ok but I wanted to use sky130_fd_pr_nfet_01v8 specifically as the model name, so is there any way so that I can get this particular model name.
d
@Ashok Kumar yes correct ,I am working on it for the same,i just cloned Nicksons git and ran magic , getting model having nfet as nshort but we require sky130fd_pr nfet
@Ashok Kumar visit https://github.com/efabless/openlane/#setting-up-the-pdk-skywater-pdk and look for sky130 setup for magic in readme.md .After following you can get sky130.tech inside magic which contains models w.r.t sky13-_fd_pr. I have yet not completed setup but still inprogress.You can check it once ._
a
try installing openLANE tools from https://github.com/nickson-jose/openlane_build_script it will contain everything.
@Matt Venn i have used your technique to label the layers following the youtube video. do you have any idea how to remove those lables and create new ones.
m
a
thank you.
@Matt Venn @Nickson Jose is it okay if we have "$SUB" and some random name as the nodes in the extracted spice netlist?
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