The PCB layout is very important to maximize
the electrical and thermal performance of the total system. General guidelines are provided,
but the form factor, board stack-up, and proximity of other components also need to be
considered to maximize the performance.
- VBUS and VOUT copper pours needs to be as short and wide as possible to
accommodate high current.
- VBUS and VOUT copper pours runs at least 150 mil (3.81 mm) straight
(perpendicular to the WCSP ball array) before making turns.
- CFLY caps needs to be placed as close as possible to the device, and the CFLY
copper pours needs to be as wide as possible until close to the IC.
- CFLY pours needs to be as symmetrical as possible between CFH pads and CFL
pads.
- Place low ESR bypass capacitors to ground for VBUS, PMID, and VOUT. These
capacitors needs to be placed as close to the device pins as possible.
- The CFLY pads needs to be as small as possible, and the CFLY caps placed as
close as possible to the device, as these are switching pins and this helps reduce
EMI.
- Do not route so the power planes are interrupted by signal traces.