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:
Jun. 26, 2001
Filed:
Jun. 30, 1999
Patrick J. Coven, Albany, OR (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A method and apparatus for reducing power droop for an inkjet printing system comprising a computer, an inkjet printer and a print cartridge. The print cartridge contains a printhead wherein the print head comprises a power supply circuit and a plurality of heater resistors that are arranged in primitive groups. The primitive groups of heater resistors are further arranged into a first and second column. The power supply circuit generates pulses that sequentially energizes one half of the heater resistor group (odd column then even column) within the same time period previously required to fire all of the heater resistors simultaneously. Thus, by employing this configuration and firing technique of the heater resistors, power droop is minimized because a reduced number of primitives are fired at any one time.