Recommend a four-layer or six-layer PCB for good
thermal performance and with maximum ground plane. 3" × 3", four-layer PCB with
2-oz. copper used as example.
Recommend having equal caps on each side of the IC. Place them right across VIN as close as possible.
Inner layer 1 is ground with the PGND to AGND net
tie.
Inner layer 2 has VIN copper pour that has vias
to the top layer VIN. Place multiple vias under the device near VIN and GND
and near input capacitors to reduce parasitic inductance and improve
thermal performance
Bottom later is GND with the BOOT trace routing.
Reference feedback to the quite AGND and routed
away from the switch node.
Make VIN trace wide to reduce the trace
impedance.