The demo board is a double-sided board. Can a single-sided board be used?
Yes. For high frequency design a double-sided board is much better. Planes can be used for power and ground. If these planes are laid out over each other a small amount of parasitic capacitance (pF) is created. This small parasitic capacitance filters very high frequency off the supply planes to the ground plane giving a cleaner voltage supply for the LM4651/52. A double-sided board also allows for a smaller layout size. A single-sided board would need larger supply bypass capacitors close to the supply pins of the LM4651/52 than a dual sided board.