[SOLVED] Capacitor layout in DACs

[Yarrow]

Hi,

I am designing a charge scaling DAC. I was wondering what distance should be used between the capacitors in a capacitor array DAC? I imagine that using minimum distance between (poly-poly) capacitors is not ideal due to increase in the parasitic capacitance via the fringing capacitance?

Thanks in advance

 

[erikl]

You probably need 2 or more metal lines for the connectivity between the single PP-caps of the array, hence the P-P parasitic fringe capacitance between the individual caps won't matter - the top plates are far from each other, anyway. The metal wires' parasitics probably determine the achievable accuracy.

 

[Yarrow]

Got it, thanks erikl!