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#analog-design
Title
# analog-design
j

Jorge Marin

03/21/2022, 4:11 PM
Hello all, I created a new project to use the repository from my MPW4 analog project, which could pass the precheck in MPW4 but didn't submit for some missing buffer blocks. The design is DRC-clean in magic using the full rules. Unfortunately, this time it fails due to "Klayout FEOL" error at the Efabless platform for MPW5. During the office hour a while ago, @User suggested to check the Klayout .xml file generated in the OG platform (at [proj_name]/jobs/mpw_precheck/[job_name]/outputs/reports/klayout_feol_check.xml in this case). The errors I see are related to nsd.1 and psd.1 in a couple of small blocks (see the screenshot below). Coming from Magic (in which I double-checked no errors are flagged for drc(full)), I don't know how to interpret this. Any ideas, anyone? @User is this a known issue? any idea how to solve it? I'm really close to the tapeout (I believe), I'd really appreciate your help!
m

Matt Venn

03/21/2022, 4:13 PM
Also adding @User and @User
👍 1
n

Nguyen Dao

03/21/2022, 4:16 PM
t

Tim Edwards

03/21/2022, 4:20 PM
@User: I'd need to see this overlaid on the layout---what does the diffusion and implants look like around the area of these errors? Usually magic solves these issues but there are ways to make it fail. There are ways to manually correct these problems, but I need to see some of the layout to advise you what to do about it.
j

Jorge Marin

03/21/2022, 4:20 PM
@User thanks for pointing to this, I assume from the conversation it's not solved yet?
t

Tim Edwards

03/21/2022, 4:21 PM
There are a couple of DRC errors in the pad cells that we have corrected upstream but that still show up in precheck. But we have now modified precheck so that it avoids checking those errors on those specific cells, so the DRC errors will not show up in precheck.
j

Jorge Marin

03/21/2022, 4:22 PM
image.png
sorry, learning Klayout on the go, is this screenshot fine? @User any idea how to solve it?
not sure if I understand, is it a design error or a tool/platform error?
m

Marwan Abbas

03/21/2022, 4:32 PM
@User could you only make the nsd and psd layers visible? (93/44 and 94/20). Then you can measure the widths that are highlighted by klayout?
j

Jorge Marin

03/21/2022, 5:07 PM
@User I'll reply here to continue the thread, thanks for clarifying The structures were generate by Magic, any idea how to update it? What's your advice? @User I'll take a look and let you know
hello, what are the equivalents of psd and nsd layers in magic?
t

Tim Edwards

03/21/2022, 7:12 PM
There are no equivalent layers in magic, although they can be manipulated with the
MASKHINTS_PSDM
and
MASKHINTS_NSDM
properties.