Design concepts of pin assignment to analog and digital chip

[circuit]

pin assignment

hi guys,

i was wondering, what are the design concepts for pin assignment to a chip which has both analog and digital sides. I can think of separating analog and digital pins thru' ground pins ? keep voltage supply away from ground pin ? please lemme know the things to be considered. thanks !

 

[rtpq]

Re: pin assignment

Yes, it is good way to isolate analog pins from noisy digital pins by ground pins, but it is not necessary to seperate supply pins from ground pins. You can just place supply/ground pin to be close to large current paths.

 

[Hughes]

pin assignment

In contrary, putting the power pin and ground pin in neighbor helps to reduce the effects of parasitic inductance.

 

[CDRCDR]

Re: pin assignment

Adding more power/GND pairs as many as possible to reduce their inductive effect.