The bulk would have to be vss, regardless. I'd connect the other three terminals also to vss, to avoid extra capacitance at the cm node. This helps with high frequency CMRR.

Hi Boris, Following your suggestion, I've connected

VSS

to all the terminals on the dummy devices. But It seems that one of them is going to be connected to CM. I was worried about having a voltage between

S

and

D

, but it seems that the subthreshold current will be negligible for this tecnhology. What do you think about dummies not having all the terminals conected to

VSS

or

VDD

? Layout and schematic match lvs on magic and klayout. cc: @Jorge Marin what do you think?

I don't see a problem.

Thanks Boris