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#openlane
Title
# openlane
t

tnt

11/28/2020, 6:03 PM
@User So ... can you confirm that power distribution isn't yet really supposed to work in
develop
? Or am I missing something ? Because AFAICT it generates a giant grid
met4
/
met5
and just completely goes over everything including the macro, shorting everything.
a

Ahmed Ghazy

12/02/2020, 12:22 PM
Have you managed to work this out?
t

tnt

12/02/2020, 12:26 PM
I mean, I got something that I think works for me. What I ended up doing is : • Still have
met5
straps in my main block, but match the 180 pitch. I need them to power the SRAM • Modify the LEF to expose all of them as power pads (also adapting obstructions) • Align it in the
user_project_wrapper
so that those pads overlad the right top level straps generated by the wrapper power grid. I also modified the PDN in the wrapper to only generate straps for
vccd1
/
vssd1
since that's all I use. Rings are still generated for all rails. I also modified it so that
met5
straps go over the macro, but
met4
straps at the top level are 'cut'/interrupted.
This is what it looks like :

https://i.imgur.com/1GpQo5X.png

a

Ahmed Ghazy

12/02/2020, 12:32 PM
Ah, I see, so you are matching the pitch to get the straps to align.
I think it's a good solution for anyone having to nest at least 2 macros inside user_project_wrapper.
t

tnt

12/02/2020, 12:33 PM
yeah. If I didn't have SRAMs I could have just disabled
met5
streaps on the inside and exposed all the
met4
streaps as power pads and let the top level connect to them.
Here I just need to make sure to align GND to GND and not GND with VCC 😄
😄 1