Datasheet

Data Sheet ADF4108
Rev. E | Page 19 of 20
PCB DESIGN GUIDELINES FOR CHIP SCALE PACKAGE
The lands on the chip scale package (CP-20-6) are rectangular.
The printed circuit board pad for these should be 0.1 mm longer
than the package land length and 0.05 mm wider than the package
land width. The land should be centered on the pad. This ensures
that the solder joint size is maximized. The bottom of the chip
scale package has a central thermal pad.
The thermal pad on the printed circuit board should be at least
as large as this exposed pad. On the printed circuit board, there
should be a clearance of at least 0.25 mm between the thermal
pad and the inner edges of the pad pattern. This ensures that
shorting is avoided.
Thermal vias can be used on the printed circuit board thermal
pad to improve thermal performance of the package. If vias are
used, they should be incorporated in the thermal pad at 1.2 mm
pitch grid. The via diameter should be between 0.3 mm and
0.33 mm and the via barrel should be plated with 1 oz. copper
to plug the via.
The user should connect the printed circuit board thermal pad
to AGND.