| 摘要 |
A printed circuit board (PCB) assembly provides a two layer capacitive trackpad sensor in which an EMI ground grid is interposed among the sensor's capacitive elements on each of its layers. The EMI grid on each of the two layers is electrically coupled via, typically, vias. The described arrangement of sensor elements (capacitor plates) and EMI ground grid traces may be incorporated into a PCB having additional layers (e.g., a four, six or eight layer PCB). If used in this manner, additional vias are provided on the PCB which permit electrical coupling between these “additional layers” and which are electrically isolated from, and shielded by, the EMI ground grid.
|
