Crack sensing for printhead having multiple printhead die
AssigneeHewlett-Packard Development Company, L.P.
InventorsDaryl E Anderson, George H Corrigan, Scott A Linn
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Abstract
An inkjet printhead including a plurality of printhead dies, each printhead die including at least one crack sense resistor, at least one analog bus connected to each printhead die, and a controller separate from the plurality of printhead dies. The controller is configured to provide a known current to the at least one crack sense resistor of each printhead die in a selectable pattern via the at least one analog bus and to determine whether the printhead dies are cracked based on resulting voltages produced on the at least one analog bus.
Claims15
An inkjet printhead comprising:
- a plurality of printhead dies, each printhead die including at least one crack sense resistor;
- at least one analog bus connected to each printhead die;
- and
- a controller, separate from the plurality of printhead dies, configured to provide a known current to the at least one crack sense resistor of each printhead die in a selectable pattern via the at least one analog bus and to determine whether the printhead dies are cracked based on resulting voltages produced on the at least one analog bus.
A wide array inkjet printhead assembly comprising:
- a plurality of printhead dies disposed on a substrate, each printhead die including as least one crack sense resistor;
- at least one analog bus disposed on the substrate and electrically coupled to the at least one crack sensor resistor of each printhead die;
- and
- an ASIC, separate from the plurality printhead dies, disposed on the substrate and configured to configured to provide a known current to the at least one crack sense resistor of each printhead die in a selectable pattern via the at least one analog bus and to determine whether the printhead dies are cracked based on resulting voltages produced on the at least one analog bus.
A method of detecting cracks in a plurality of printhead dies disposed on a substrate of an inkjet printhead, the method including:
- disposing at least one crack sense resistor on each printhead die of the plurality of printhead dies;
- disposing at least one analog bus on the substrate which is electrically coupled to the at least one crack sense resistor of each printhead die;
- disposing an application specific integrated circuit on the substrate separate from the plurality of printhead dies;
- providing, with the ASIC, a known current via the at least one analog bus to the at least one crack sense resistor of each printhead die according to a selectable pattern;
- comparing, with the ASIC, a resulting voltage produced on the analog bus in response to the known current being provided to the at least one crack sense resistor of each printhead die to a predetermined threshold to determine whether the printhead die is cracked.
Dependencies are inferred from the claim text.