On-die actuator evaluation with pre-charged thresholds
AssigneeHewlett-Packard Development Company, L.P.
InventorsDaryl E Anderson, Eric Martin, James Michael Gardner
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Abstract
A fluid ejection die includes a number of actuator sensors to sense a characteristic of a corresponding actuator and to output a first voltage corresponding to the sensed characteristic. Multiple coupled actuator sensors and actuators are grouped as primitives on the fluid ejection die. The die also includes a pre-charge device per primitive to pre-charge a corresponding threshold voltage storage device to a threshold voltage. The die also includes an actuator evaluation die per primitive to evaluate an actuator characteristic of any actuator within the primitive.
Claims15
A fluid ejection die comprising:
- a number of actuator sensors disposed on the fluid ejection die to sense a characteristic of a corresponding actuator and output a first voltage corresponding to the sensed characteristic, wherein:
- each actuator sensor is coupled to a respective actuator;
- and
- multiple coupled actuator sensors and actuators are grouped as primitives on the fluid ejection die;
- a pre-charge device per primitive to pre-charge a corresponding threshold voltage storage device to a threshold voltage;
- and
- an actuator evaluation device per primitive to evaluate an actuator characteristic of any actuator within the primitive based on the first voltage and a pre-charged threshold voltage.
A fluid ejection system comprising:
- multiple fluid ejection dies, wherein a fluid ejection die comprises:
- a number of drive bubble detection devices to output a first voltage indicative of a state of a corresponding actuator, wherein:
- each drive bubble detection device is coupled to a respective actuator;
- and
- multiple coupled drive bubble detection devices and actuators are grouped as primitives on the fluid ejection die;
- a pre-charge device per primitive to pre-charge a corresponding threshold voltage storage device to a threshold voltage;
- and
- an actuator evaluation device per primitive to evaluate an actuator characteristic of the actuator based at least in part on a comparison of the first voltage and a threshold voltage.
A method comprising:
- selectively pre-charging a threshold voltage storage device to a threshold voltage;
- receiving an activation pulse for activating an actuator of a primitive on a fluid ejection die;
- activating the actuator based on the activation pulse to generate a first voltage measured at a corresponding actuator sensor, wherein the corresponding actuator sensor:
- is disposed on the fluid ejection die;
- and
- is coupled to the actuator;
- and
- evaluating an actuator characteristic of the actuator based at least in part on a comparison of the first voltage and a pre-charged threshold voltage.
Dependencies are inferred from the claim text.