AD7873ACPZ datasheet(24/29 Pages) AD

24 / 29 page

Data Sheet

AD7873

Rev. F | Page 23 of 28

GROUNDING AND LAYOUT

For information on grounding and layout considerations for the

AD7873, refer to Application Note AN-577, Layout and

Grounding Recommendations for Touch Screen Digitizers.

PCB DESIGN GUIDELINES FOR

CHIP SCALE PACKAGE

The lands on the chip scale package (CP-32) 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 GND.

AD7873ACPZ Datasheet(PDF) 24 Page - Analog Devices