Invalidity dossier
US 6543883
Fluid ejection device with drive circuitry proximate to heating element
Current assignee: Hewlett Packard Development Co LP
Added 9/23/2026, 9:55:45 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US6543883B1
Title: Fluid ejection device with drive circuitry proximate to heating element
Patent number / application: US6543883B1; Application US09/967,665
Inventors: Simon Dodd; Joseph M. Torgerson
Original assignee: Hewlett Packard Co. Current assignee listed as Hewlett Packard Development Co LP.
Key dates: Priority/filing date 2001-09-29; publication date 2003-04-08; granted 2003-04-08. Status listed as "Expired - Lifetime," with anticipated expiration 2021-09-29.
Purpose: The invention relates to fluid ejection devices and, more particularly, to proximate positioning of drive circuitry with respect to heating elements. In printheads, fluid is heated by resistors activated in response to associated transistors. The drive transistors have conventionally been located a distance from the resistors to protect them from high heat, shortening transistor life, and to minimize mechanical pounding of the transistors by fluid-bubble explosions.
Plain-language scope: According to the supplied definitions, the printhead includes a firing chamber from which heated fluid is ejected; a resistor that heats fluid in the firing chamber, the resistor formed in a substrate underlying the firing chamber; and a transistor electrically coupled with the resistor, also formed in the substrate. The transistor is positioned proximate to the resistor, at a distance within 60 microns thereof. The substrate has a width that corresponds to the distance between the resistor and the transistor. The specification describes a thin film substructure/die (e.g., silicon) with thin film heater resistors, an ink barrier layer, an orifice/nozzle plate, ink chambers and channels, and gold bonding pads.
Source: https://patents.google.com/patent/[US6543883](/patent/US6543883)/en
What the excerpt does not establish: It does not include the full claim set or independent/dependent claim language; the complete specification, drawings, or omitted text; the exact claim language defining the 60-micron limitation; foreign priority details beyond listed TW, SG, GB, KR, and JP filings; or any legal conclusions as to validity, enforceability, or claim scope. The 60-micron figure derives from the excerpted "Definitions" summary, not from a verified claim. No litigation, ownership-transfer, validity, or prior-art analysis is offered.
Generated 10/1/2026, 9:33:55 PM
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Litigation summary
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Proceedings on file (0)
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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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