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:
Mar. 01, 2005
Filed:
Jun. 17, 2003
Somei Kawasaki, Saitama, JP;
Hiroyuki Maru, Kanagawa, JP;
Somei Kawasaki, Saitama, JP;
Hiroyuki Maru, Kanagawa, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
Power consumed by a resistor connected between a first power supply and a drive control circuit is controlled by a power driving circuit connected to a second power supply. When the value of current that flows into the resistor fluctuates, the value of current output from power driving circuit to a control terminal of the drive control circuit is controlled in such a manner that power consumed is the same as that when the resistance value of the resistor is a set value. As a result, the value of power consumed by the resistor is rendered substantially constant without being influenced by a variation in the resistance value of the driven resistor or by the power supply voltage. If such a drive circuit is used in driving the printhead of a printing apparatus, stabilized drive can be achieved with the minimum margin, power consumption can be suppressed and the lifetime of the printhead can be prolonged.