Rounded-corner pads are cool.
U9 was throwing clearance errors with reasonable limits, but a bit of rounding fixed it. It's easy to do in PADS.
Good for high voltages, too.
It would seem this is your first time at the rodeo. Rounded pads are the default when I lay out boards. I don't even use a fancy, dancy package. I use FreePCB. Works great and it just works.
I suppose one's taste is a matter of past experience. In the really old days, with Bishop tapes, rounded pads were standard. But after decades of rectangular pads, I only use the rounded form when needed for clearance, when near high voltages, or if a component's datasheet makes a point about it. It still feels uncomfortable.
Welcome to 1983?
A lot of packages draw soldermask as a direct expansion of the pad shape. Which means square pads beget square mask openings. This is bad for web widths, especially around QF{N|P}s. Even a token 5% or whatever rounding, is usually adequate to trick it into using a correctly rounded mask opening and the problem goes away. But 20-50% rounding looks better.
I've seen square mask openings cause accidental exposed copper on nearby traces. That's just retarded.
Tim
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