An aspect of the present disclosure is a liquid ejection apparatus including: a liquid ejection head including a conversion element that generates energy required to eject liquid, a first protection layer that blocks contact between the conversion element and the liquid, a second protection layer that partially covers the first protection layer and functions as a first electrode, a second electrode that is electrically connected to the first electrode through the liquid, and an ejection port that ejects the liquid, and a control unit configured to control a potential difference between the first electrode and the second electrode in printing to a predetermined value by changing at least one of potentials of the first electrode and the second electrode. The control unit sets the potential difference based on at least one of a condition and a configuration of the liquid ejection head.

An example provides a fluid ejection apparatus including a fluid feed slot along a length of a print head die of the fluid ejection apparatus to supply a fluid to a plurality of drop ejectors, control circuitry adjacent to at least one side of the fluid feed slot to control ejection of drops of fluid from the plurality of drop ejectors, and a single power supply connector at an end of the print head die to supply power to the control circuitry.

An example provides a fluid ejection apparatus including a fluid feed slot to supply a fluid to a plurality of drop ejectors, a first rib at a first side of the fluid feed slot and supporting drop ejection circuitry to control ejection of drops of the fluid from the plurality of drop ejectors, and a second rib at a second side, opposite the first side, of the fluid feed slot supporting a thermal sensor to facilitate determination of a temperature of the first rib and the second rib.

In some examples, a piezoelectric printhead assembly can include a plurality of piezoelectric micro-electro mechanical system (MEMS) dies, and application-specific integrated circuit (ASIC) dies electrically connected to the piezoelectric MEMS dies.

A die for a printhead is provided in examples. The die includes a number of fluidic actuator arrays. A data block is associated with each of the plurality of fluidic actuator arrays. The die includes an interface comprising a data pad and a clock pad, wherein a data bit value present at the data pad is loaded into a first data block corresponding to a first fluidic actuator array on a rising clock edge and loaded into a second data block corresponding to a second fluidic actuator array on a falling clock edge.

A wafer structure is disclosed and includes a chip substrate and a plurality of inkjet chips. The chip substrate is a silicon substrate which is fabricated by a semiconductor process on a wafer of at least 12 inches. The plurality of inkjet chips include at least one first inkjet chip and at least one second inkjet chip. The plurality of inkjet chips are directly formed on the chip substrate by the semiconductor process, respectively, and diced into the at least one first inkjet chip and the at least one second inkjet chip, to be implemented for inkjet printing.

A recording apparatus includes: a liquid ejection head including a heating element, a first protection layer that blocks contact between the heating element and liquid, a second protection layer that covers at least a portion of the first protection layer to be heated by the heating element and that functions as a first electrode, a second electrode that is electrically connected to the first electrode through the liquid, an ejection port that ejects the liquid, and a temperature detection element that corresponds to the heating element, and a detection unit configured to detect a feature point in a temperature curve that indicates a relationship between time and temperature, in which a combination of a potential set for the first electrode and a potential set for the second electrode in a case where printing is performed varies from that in a case where the detection unit detects the feature point.

There is provided a liquid discharge apparatus for forming an image on a medium by discharging a liquid, including: a first discharge head that discharges a liquid; and a first temperature indicating section provided in the first surface, in which the first temperature indicating section indicates that a temperature of the first temperature indicating section is lower than a first threshold value in a first state, and indicates that the temperature of the first temperature indicating section is equal to or higher than the first threshold value in a second state, and the first state and the second state change reversibly, and at least a part of the first temperature indicating section overlaps at least a part of the first propagation wiring in a normal direction of the wiring substrate.

In one example in accordance with the present disclosure, a fluidic die assembly is described. The fluidic die assembly includes a rigid substrate having a bend therein. A fluidic die is disposed on the rigid substrate. The fluidic die is to eject fluid from a reservoir fluidly coupled to the fluidic die. The fluidic die includes an array of ejection subassemblies. Each ejection subassembly includes an ejection chamber to hold a volume of fluid, an opening, and a fluid actuator to eject a portion of the volume of fluid through the opening. The fluidic die assembly also includes an electrical interface disposed on the rigid substrate to establish an electrical connection between the fluidic die and a controller. The fluidic die and the electrical interface are disposed on a same surface on opposite sides of the bend.

In some examples, a print bar fabrication method comprises placing printhead dies face down on a carrier, placing a printed circuit board on the carrier, wire bonding each printhead die of the printhead dies to the printed circuit board, and overmolding the printhead dies and the printed circuit board on the carrier, including fully encapsulating the wire bonds.