markdown/gh_discussions/Query/3355.md

set_io_pin_constraint and pin distance

Tool: Pin Placer

Subcategory: Pin placement behavior

Conversation

oharboe

@nerriav It looks like minimum pin distance is only availble globally for a macro, not per set_io_pin_constraint?

https://openroad.readthedocs.io/en/latest/main/src/ppl/README.html

We would like pins to use the entire(initially) width/height of the macro edge to minimize contention at the top level where the macro is used. Currently we add extra horizontal distance in the example below to handle routing congestion at the top level. Routing congestion happens even with horizontal routes, because the horizontal routes will intersect a bit with the PDN.

maliberty

I don't understand what you are asking here. Are you talking about -corner_avoidance ?

oharboe

@nerriav discovered that -region:* and -region:0-100 to is not identical if the regions is 100 wide. The pins are spread evenly when a range is specified (latter) and bunched together more closely if * is specified.

@maliberty Is this intentional?