Switch scanning means for use with integrated circuits
US4277784A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 13, 1979 |
| Grant date | Jul 7, 1981 |
| Priority date | — |
| Expiry date | Jul 13, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G3/04
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
Method and apparatus for generating a digital data word representative of the position of a switch element which is selectively engageable with one of a plurality of driver conductors which are utilized for conducting actuating signals from a source to a data display system of the type having a plurality of display elements for visually indicating alphanumeric data. The display elements have visually perceptible and imperceptible data indicating states and are characterized by a lagging response to either the application or interruption of the actuating signal wherein a turn-on or turn-off transition interval elapses during a change from one state to the other with the preexisting state of the display element appearing to an observer to remain unchanged during the transition interval. The actuating signals are periodically applied during a load energizing interval through one or more of the driver conductors and are interrupted during a sampling interval. The load energizing interval is much longer in duration relative to the duration of the sampling interval, with the duration of the sampling interval being substantially less than the duration of the turn-off transition interval. …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.