Corner Cell importance?

[predator89]

Hello All,

I have a pad ring with corner cell to allow the connectivity of the analog and digital power rails.
Since I am planning to reduce the die area of the chip, I was planning to remove one of the corner cell.
So I am confused if it is recommended to keep all 4 corner cell at each corner of the die for reliability reason or I can remove one to achieve my required area requirement.

Any suggestions are welcome.

Thanks!

 

[jjx]

(Cannot visualize exactly how you would save space by removing a corner cell.)

You can remove one, just make sure you have the supplies properly spaced and do not rely on signals traveling 3/4 of the distance around to guarantee ESD and possible POR-signals, etc.

Seal ring takes care of die stress.

Bonding house might have certain requirements on angles, etc. Keepout distances (from pad surfaces to active area) might influence what you can put in the corner where there is no corner.