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:
Jan. 25, 2011
Filed:
Nov. 03, 2009
John Robert Sheahan, Balmain, AU;
Mark Jackson Pulver, Balmain, AU;
Brian Christopher Morahan, Balmain, AU;
Alireza Moini, Balmain, AU;
Timothy Peter Gillespie, Balmain, AU;
Michael John Webb, Balmain, AU;
Marcelle Louisa Gannon, Balmain, AU;
Kia Silverbrook, Balmain, AU;
John Robert Sheahan, Balmain, AU;
Mark Jackson Pulver, Balmain, AU;
Brian Christopher Morahan, Balmain, AU;
Alireza Moini, Balmain, AU;
Timothy Peter Gillespie, Balmain, AU;
Michael John Webb, Balmain, AU;
Marcelle Louisa Gannon, Balmain, AU;
Kia Silverbrook, Balmain, AU;
Silverbrook Research Pty Ltd, Balmain, New South Wales, AU;
Abstract
Provided is a printhead integrated circuit for an inkjet printer that has a nozzle and a corresponding actuator for ejecting ink through the nozzle. The Printhea IC also has drive circuitry for controlling the operation of the actuator. The drive circuitry has an open actuator test circuit comprising an open actuator test input, a column enable input and a row enable input, a drive transistor operatively linking said actuator to a power supply, a bleed transistor arranged in parallel with the actuator, a sense transistor operatively linking an output of the drive transistor and inputs of the actuator and bleed transistor to a sensing node. Actuating the actuator to eject ink by enabling the column and row enable inputs, deactivates the bleed transistor and activates the drive transistor to link the actuator to the power supply. Testing the actuator involves enabling the open actuator test input to activate the sense transistor, so that the actuator is short-circuited and the sense node is pulled high if the actuator is open-circuit.