Meaning of "Single point ground"?

[thomasx]

Hi

In the layout recommendations in the datasheet for the UCC28C54Q flyback controller, they mention "Single point ground". It is not clear to me what they mean by that.

The signal ground has lot's vias between top and bottom, do these NOT connect with the internal ground plane?

Also some of the components connecting with the power ground are through hole components, do these pins also NOT connect with the internal ground plane?

Is the "Single point ground" the only connection with the internal ground plane, or what do they mean?

Thanks!

[Faringdon]

Its a layout methodology to help you to avoid running power switching currents with high di/dt through lengths of your control ground.
Eg the output divider, say, connects to ground, and the controller connects to ground also, but if high di/dt runs in the copper between these connection places, then they
wont really be at the same  potential. Since V = L di/dt
Attached is a doc on it.