The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 30, 1996
Filed:
Sep. 26, 1994
Michael B Saunders, Corvallis, OR (US);
Andre Garcia, Corvallis, OR (US);
S Dana Seccombe, Foster City, CA (US);
Rajeev Babyal, Corvallis, OR (US);
James R Hulings, Fort Collins, CO (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
The interconnections for transmitting print commands from a printer to a printhead are reduced by the use of on-printhead circuitry. In a basic embodiment, the printhead driver circuitry includes a matrix of drivers controlled by gates, power and control interconnections. Interconnections are reduced by enabling rows and columns of drivers with the power and control interconnections. A multiplexer may also be added to further reduce control interconnections. In an advanced embodiment, the printhead driver circuitry includes a register for converting a serial stream of print enable signals from the printer into a format for applying such signals concurrently to switching devices for one or more heater resistors. An address generator on the printhead generates address signals in response to an address generating signal from the printer. The printer provides constant power to the printhead so that energizing of the heater resistors is a function of the address and print enable signals and not of the power. Variations on the basic and advanced embodiments are also shown and described.