Invalidity dossier
US 6104821
Electrical hearing aid device with high frequency electromagnetic radiation protection
Current assignee: Sivantos GmbH
Added 9/24/2026, 1:47:00 AM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6,104,821
Title: Electrical hearing aid device with high frequency electromagnetic radiation protection
Patent number: US 6,104,821 A
Application number: US 08/919,210
Inventor: Kunibert Husung
Original assignee: Siemens Audiologische Technik GmbH
Current assignee (as listed): Sivantos GmbH
Priority date: 1996-10-02
Filing date: 1997-08-28
Grant/publication date: 2000-08-15
Status (as listed): Expired – Lifetime; anticipated expiration 2017-08-28
Purpose: Parasitic electromagnetic radiation can be demodulated in the active components of a hearing aid circuit, producing low-frequency noise that degrades or disables the device. The patent addresses protection against high-frequency electrical waves, particularly line-bound RF currents reaching the integrated circuit (IC).
Plain-language scope: The hearing aid has a housing containing an integrated amplifier circuit, at least one microphone, switch and/or connection means, filter means, amplifier means, a voltage source, and at least one earphone. Protection is achieved by placing filter elements in the electrical terminals of the integrated amplifier circuit, directly at the IC, so line-bound RF currents are shielded or diverted. The filter elements may be passive filters of the first, second, or higher order. Terminals covered include those to the microphone, earphone, battery, volume control, and audio input. In an especially advantageous embodiment, the filter elements are RF-quality capacitors embedded in a filter substrate, preferably connected to a reference potential in a star-point-like manner, with the hearing aid IC mounted on and directly connected to that substrate board. The reference potential may be a ground layer of a printed circuit board or a conductive housing section.
Source: https://patents.google.com/patent/US6104821/en
What the excerpt does not establish: It does not provide the full description, all claims, or the complete list of cited prior art beyond DE-C-43 43 702 and DE-C-43 43 703. It does not establish claim scope, validity, enforceability, or the accuracy of the listed assignee/status data, which the source itself labels as assumptions. No litigation or ownership-transfer details are included.
Generated 10/1/2026, 9:31:06 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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