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CapTIvate™ Touch Getting Started Manual
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7
Ground copper
se grid-like copper plating (line width 8mil, grid width 64mil, angle
45°).
Self-capacitive design, double-sided copper-clad, selective copper-
clad directly under the button.
Mutual capacitance type design, can choose only the bottom
surface of copper.
8
Series resistance, TVS tube, EMC filter
capacitor placement
Place within 10 mm of MCU pin.
8
Moisture and liquid resistance
Self-inductive solution: It is recommended to reduce the grounding
copper and improve the touch sensitivity to reduce the parasitic
capacitance change caused by water.
Mutual-capacitive scheme: reference
Touch Buttonpad Reference Design
In terms of sensitivity, buttons and slider wheels with a width similar to a finger touch, and narrower and shorter
sensor traces can enhance the capacitance change caused by touch. Fewer vias and thinner copper can reduce the
size of the capacitance to ground. However, grounding copper also directly affects EMC's anti-noise ability. The
specific laying range and grid density need to be adjusted according to actual needs. Since capacitive touch is both
a source of interference and a sensitive device, for EMC considerations, in addition to adding protection devices, it
is recommended to keep away from other signal lines or devices during layout.
