Ground switching technique for silkscreened digitizer grids
US4853499A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 12, 1988 |
| Grant date | Aug 1, 1989 |
| Priority date | — |
| Expiry date | Dec 12, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F3/046
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and associated circuitry for use in an electromagnetic digitizer having a plurality of first grid conductors connected from a first multiplexer controlled by a first enable input to ground and a plurality of second grid conductors connected from a second multiplexer controlled by a second enable input to ground and crossing over the first grid conductors at multiple points for eliminating errors caused by capacitively coupled signals between the grid conductors at the cross over points. The method comprises, connecting a first switch having a control input for switching the first switch to a closed position in series with the connection of the first grid conductors to ground; connecting a second switch having a control input for switching the second switch to a closed position in series with the connection of the second grid conductors to ground; applying the first enable input simultaneously to the control input of the second switch and the first multiplexer whereby the connection to ground of the second grid conductors is broken when the first multiplexer is enabled; and, applying the second enable input simultaneously to the control input of the first switch and the sec…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.