Low EMI capacitive trackpad
US7394458B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2004 |
| Grant date | Jul 1, 2008 |
| Priority date | — |
| Expiry date | Jan 27, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05K1/11
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.