The printed-circuit-board (PCB) layout is an
important step to maintain the high performance of the device. See
Layout Example for the
recommended low EMI PCB layout.
- Place the
input and output capacitors as close as possible to the IC. This action
keeps the power traces short. Routing these power
traces direct and wide results in low trace
resistance and low parasitic inductance.
- Connect
the low side of the input and output capacitors
properly to the GND pin to avoid a ground potential
shift.
- Take
special care to avoid noise being induced. The sense
traces connected to FB is a signal trace. Keep these
traces away from SW nodes. The connection of the
output voltage trace for the FB resistors must be
made at the output capacitor.
- Refer to
Layout Example for an
example of component placement, routing, and thermal
design with good EMI performance.