@User: Where are you getting your current density limit numbers from? I have not found any electromigration rules for this process. You're using some reference with standard values/constants/equations for aluminum interconnect?
05/21/2021, 12:57 AM
general numbers for aluminum interconnect
05/21/2021, 1:15 AM
Based on values from a very similar process, I would estimate 1.5mA/um for metal3. There are two stubs at 24um wide, so the power pad as is should be good for nearly 75mA continuous. There is no metal3 to the sides, so I can stretch that out, not indefinitely, but maybe to 3x, then connect them into a single stack of m3 + m4 + m5 at the edge of the user area. Then you just need to connect the same stack of m3 + m4 + m5 at the position of the pins where there is only a m3 pin currently. Then you should be able to get 225mA through the pad.
05/21/2021, 8:20 PM
that sounds like it should work!
@Tim Edwards I have reached the point where I am working on integration (Yay!). So just to be clear, I need to connect M3 + M4 + M5 to the edge of the port connection as the same width as the M3 is currently?
05/27/2021, 11:52 PM
Yes, that's right. I'll need to hand-edit the padframe layout; I think there is some routing in it that OpenLane does, so I will wait until that is finished before I make manual changes to it. But yes, that's the plan, to take the existing metal 3 and triple it up to include metal 4 and metal 5.