Abstract: A fluid printhead including at least one fluid ejection element. The fluid ejection element includes a fluid chamber, a throat portion through which fluid is provided to the fluid chamber, and a heater element disposed within the fluid chamber. The fluid ejection element also includes a printhead condition detection system. The printhead condition detection system includes a first electrode at least a portion of which is disposed within the fluid chamber, the first electrode configured to receive a step voltage, a second electrode disposed within the throat portion, and a sense circuit electrically connected to the second electrode that generates an output based on the application of the step voltage to the first electrode as an indication of printhead condition.

Abstract: A fluid printhead including at least one fluid ejection element. The fluid ejection element includes a fluid chamber, a throat portion through which fluid is provided to the fluid chamber, and a heater element disposed within the fluid chamber. The fluid ejection element also includes a printhead condition detection system. The printhead condition detection system includes a first electrode at least a portion of which is disposed within the fluid chamber, the first electrode configured to receive a step voltage, a second electrode disposed within the throat portion, and a sense circuit electrically connected to the second electrode that generates an output based on the application of the step voltage to the first electrode as an indication of printhead condition.

Abstract: A fluid printhead including at least one fluid ejection element. The fluid ejection element includes a fluid chamber, a throat portion through which fluid is provided to the fluid chamber, and a heater element disposed within the fluid chamber. The fluid ejection element also includes a printhead condition detection system. The printhead condition detection system includes a first electrode at least a portion of which is disposed within the fluid chamber, the first electrode configured to receive a step voltage, a second electrode disposed within the throat portion, and a sense circuit electrically connected to the second electrode that generates an output based on the application of the step voltage to the first electrode as an indication of printhead condition.

Abstract: A fluid printhead including a plurality of heater elements that are driven to nucleate bubbles in fluid so that the fluid is ejected from the printhead in the form of drops, a plurality of drive elements, each drive element selectively driving a corresponding one of the plurality of heater elements in accordance with a printer controller, and a drop detection system that includes a plurality of drop detection cells, each drop detection cell detecting a change in electrical resistance of a corresponding one of the plurality of heater elements that occurs upon drop formation.

Abstract: A fluid printhead including a plurality of heater elements that are driven to nucleate bubbles in fluid so that the fluid is ejected from the printhead in the form of drops, a plurality of drive elements, each drive element selectively driving a corresponding one of the plurality of heater elements in accordance with a printer controller, and a drop detection system that includes a plurality of drop detection cells, each drop detection cell detecting a change in electrical resistance of a corresponding one of the plurality of heater elements that occurs upon drop formation.

Abstract: A fluid printhead including a plurality of heater elements that are driven to nucleate bubbles in fluid so that the fluid is ejected from the printhead in the form of drops, a plurality of drive elements, each drive element selectively driving a corresponding one of the plurality of heater elements in accordance with a printer controller, and a drop detection system that includes a plurality of drop detection cells, each drop detection cell detecting a change in electrical resistance of a corresponding one of the plurality of heater elements that occurs upon drop formation.

Abstract: A fluid printhead including a plurality of heater elements that are driven to nucleate bubbles in fluid so that the fluid is ejected from the printhead in the form of drops, a plurality of drive elements, each drive element selectively driving a corresponding one of the plurality of heater elements in accordance with a printer controller, and a drop detection system that includes a plurality of drop detection cells, each drop detection cell detecting a change in electrical resistance of a corresponding one of the plurality of heater elements that occurs upon drop formation.

Abstract: A fluid printhead including at least one fluid ejection element. The fluid ejection element includes a fluid chamber, a throat portion through which fluid is provided to the fluid chamber, and a heater element disposed within the fluid chamber. The fluid ejection element also includes a printhead condition detection system. The printhead condition detection system includes a first electrode at least a portion of which is disposed within the fluid chamber, the first electrode configured to receive a step voltage, a second electrode disposed within the throat portion, and a sense circuit electrically connected to the second electrode that generates an output based on the application of the step voltage to the first electrode as an indication of printhead condition.

Abstract: A fluid printhead including at least one fluid ejection element. The fluid ejection element includes a fluid chamber, a throat portion through which fluid is provided to the fluid chamber, and a heater element disposed within the fluid chamber. The fluid ejection element also includes a printhead condition detection system. The printhead condition detection system includes a first electrode at least a portion of which is disposed within the fluid chamber, the first electrode configured to receive a step voltage, a second electrode disposed within the throat portion, and a sense circuit electrically connected to the second electrode that generates an output based on the application of the step voltage to the first electrode as an indication of printhead condition.

Abstract: A fluid printhead including at least one fluid ejection element. The fluid ejection element includes a fluid chamber, a throat portion through which fluid is provided to the fluid chamber, and a heater element disposed within the fluid chamber. The fluid ejection element also includes a printhead condition detection system. The printhead condition detection system includes a first electrode at least a portion of which is disposed within the fluid chamber, the first electrode configured to receive a step voltage, a second electrode disposed within the throat portion, and a sense circuit electrically connected to the second electrode that generates an output based on the application of the step voltage to the first electrode as an indication of printhead condition.

Abstract: A flowmeter including a fluid flow channel formed on a substrate that directs a fluid from an upstream position to a downstream position. A heater is disposed between the upstream and downstream positions. A first temperature sensor detects temperature of the fluid at the upstream position and a second temperature sensor detects temperature of the fluid at the downstream position. At least one third temperature sensor detects temperature of the heater. A controller maintains the heater at a predetermined temperature based on the temperature sensed by the at least one third temperature sensor. A flow measurement output circuit generates a gain stage output of a temperature differential between the temperature detected by the first temperature sensor and the temperature detected by the second temperature sensor.

Abstract: A temperature control circuit for an inkjet printhead including a temperature sensor portion that generates an output current made up of the sum of a current proportional to a sensed temperature on the inkjet printhead and an offset current, and an offset current correction portion that generates a correction current that is subtracted from the output current to at least partially compensate for the offset current, the output current as compensated by the correction current being output as a temperature control circuit output current.