Membrane switch structure providing electrostatic discharge protection
US6323445A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 28, 2000 |
| Grant date | Nov 27, 2001 |
| Priority date | — |
| Expiry date | Apr 28, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2239/008
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A membrane switch structure providing electrostatic discharge (ESD) protection has three layers of insulating material, including two outer layers containing on their inside opposing surfaces printed conductive circuit patterns which may be selectively brought into electrical contact with each other through contact apertures provided in an intermediate insulting layer. An ESD protection circuit is provided in close proximity to at least one of the two outer layers, e.g., by printing the pattern on a backside of one of the outer layers in the same manner that printing of the circuit pattern is carried out. The ESD protection circuit pattern replicates, at least generally, all or a portion of the layout of the conductive circuit patterns. The ESD protection circuit can be efficiently fabricated and offers effective protection of the membrane switches from ESD events that can cause device operation problems in, for example, computer keyboards.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.