How do you plan to develop the requirements /
"care-abouts" for this clock field? Clock alignment
and parasitic matching probably matter a lot. How
much and how, you have to observe & alter.
If single input multi-sampled and parceled out to
1 of 4, that's a < 250ps settling time to sub-LSB.
What've you got, for that? My gut says the actual
sub-ADCs need figured out first, so you know what
you're driving and any pain or bonuses that hide in
those details (like, maybe youhave more than 4
complementary phases, staggered early / late,
whatever).
Clock tree is more of a "make it so, in the end" than
"Start here and finish it off", you'll be touching it again
(and more than once) in the course of layout. If your
project encompasses layout.