An example of a proper layout for the TPS92200 device is shown in Figure 10-1.
- Creating a large GND plane for good electrical and thermal performance is important.
- The IN and GND traces must be as wide as possible to reduce trace impedance.
Wide traces have the additional advantage of providing excellent heat
dissipation.
- Thermal vias can be used to connect the top-side GND plane to additional printed-circuit board (PCB) layers for heat dissipation and grounding.
- The input capacitors must be located as close as possible to the IN pin and the GND pin.
- The SW trace must be kept as short as possible to reduce radiated noise and EMI.
- Do not allow switching current to flow under the device.
- The FB trace must be kept as short as possible and placed away from the
high-voltage switching trace and the ground shield.
- In higher-current applications, routing the load current of the current-sense
resistor to the junction of the input capacitor and GND node can be
necessary.