1.2 Layout Considerations

The MCP16503 PMIC requires at least nine vias from the ICs Exposed Pad to the ground (GND) plane, to dissipate the generated heat. The GND plane can be increased or decreased based on the ambient temperature, air flow or other devices that generate heat. The rule of thumb is that the GND plane must be as big as possible. It is also recommended to connect the input and output capacitor GND connections.

See Board Design for a PCB layout example. For low EMI (Electromagnetic Interference) emissions, the switching node of the Buck regulators should be routed on an internal plane, surrounded/enclosed by input supply voltage distribution or GND planes.