Electrostatic discharge protection in a portable communication device

Patent 6207912 Issued on March 27, 2001. Estimated Expiration Date:

March 2, 2018. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventor

Persson, Goran

Assignee

Telefonaktiebolaget LM Ericsson

Application

No. 032794 filed on 03/02/1998

US Classes:

200/305, Electrical shield200/512Membrane type

Examiners

Primary: Luebke, Renee S.

Attorney, Agent or Firm

Burns, Doane, Swecker & Mathis, L.L.P.

Foreign Patent References

0 302 350 EP. 07/13/1988
0 358 885 EP. 07/13/1989
0 367 530 EP. 10/13/1989
0 703 591 EP. 07/13/1995

International Class

H01H 9/1/2

Foreign Application Priority Data

1997-03-03 SE

Abstract

A portable communication device has an electronic circuit board arranged inside a housing, and a keypad, the individual keys of which are arranged, when depressed, to collapse a respective tactile dome on a domefoil interposed between the keypad and the circuit board, so as to establish electric contact with a respective contact point on the circuit board. The domefoil is formed as a non-conductive sheet providing an airtight and/or electrostatic seal between the keypad and the circuit board. The domefoil protects the circuit board from electrostatic discharge.