Printheads and methods of operation. In one embodiment, a printhead includes a plurality of jetting channels comprising first jetting channels configured to jet a first print fluid and second jetting channels configured to jet a second print fluid, and a driver circuit communicatively coupled to actuators of the jetting channels. The driver circuit receives a drive waveform comprising first jetting pulses provisioned for the first print fluid and second jetting pulses provisioned for the second print fluid, and gating signals comprising a first active gating signal designated for jetting the first print fluid and a second active gating signal designated for jetting the second print fluid. The driver circuit selectively applies the first jetting pulses to actuators of the first jetting channels based on the first active gating signal, and selectively applies the second jetting pulses to actuators of the second jetting channels based on the second active gating signal.

A liquid discharge apparatus includes a head and a switching device. The head includes a piezoelectric element and a pressure chamber configured to discharge liquid. The switching device is configured to select application or non-application of a drive voltage waveform to the piezoelectric element. The drive voltage waveform includes a discharge waveform to pressurize and discharge the liquid in the pressure chamber and a damping waveform to suppress residual vibration in the pressure chamber. The damping waveform is disposed after the discharge waveform in time series. The switching device includes a switch and a diode. The switch is configured to be turned on in a falling waveform element of each of the discharge waveform and the damping waveform. The diode is connected in parallel with the switch in a direction opposite to the falling waveform element of each of the discharge waveform and the damping waveform.

There is provided a method for controlling driving of an inkjet head including recording elements each including a nozzle and a driving element. The method includes a pulse width setting step. In this step, when a predetermined number of ink droplets ejected according to the predetermined number of driving pulses are made to land in the same pixel range, the predetermined number of first driving pulses each having a pulse width longer than a reference pulse width and the predetermined number of second driving pulses each having a pulse width shorter than the reference pulse width are combined for each of the recording elements and obtained combinations are respectively output to the recording elements. The predetermined number is two or more.

A piezoelectric device includes a substrate on which a plurality of recesses are arranged in a first direction, a vibration plate, and a piezoelectric actuator having a first electrode, a second electrode and a third electrode, a fourth electrode, and a piezoelectric layer, in which a plurality of active portions are provided, the second electrode and the third electrode are provided from an edge of a region facing a recess to an outside of the recess, the first electrode is formed between the second electrode and the third electrode, the second electrode, the third electrode, and the fourth electrode configure common electrodes for the plurality of active portions, and the first electrode configures an individual electrode provided independently for each of the active portions.

A liquid ejecting apparatus includes a drive element, and a drive circuit that outputs a drive signal that drives the drive element, wherein the drive circuit includes a modulation circuit that modulates a base drive signal to output a modulation signal, an amplifier circuit that amplifies the modulation signal to output an amplified modulation signal, a demodulation circuit that demodulates the amplified modulation signal to output the drive signal, and a substrate on which the modulation circuit, the amplifier circuit, and the demodulation circuit are provided, wherein the substrate includes a base material includes a metal and a first layer laminated on the base material, wherein the first layer includes a first propagation wire through which at least one of the amplified modulation signal and the drive signal propagates, and wherein the base material has a thickness greater than a thickness of the first layer.

A liquid discharging apparatus includes: a channel unit having a nozzle and an individual channel; an actuator applying pressure to liquid in the individual channel to discharge the liquid from the nozzle; a driving circuit electrically connected to the actuator and supplying driving signal to the actuator; and a controller. In a case of determining that a single-sided recording is to be executed, the controller supplies the driving signal corresponding to each of gradation values for each of pixels when discharging the liquid toward one of a first surface and a second surface of a recording medium; in a case of determining that the double-sided recording is to be executed, the controller supplies the driving signal corresponding to each of the gradation values for each of the pixels when discharging the liquid toward the first surface and when discharging the liquid toward the second surface.

A print head having an ejection portion that ejects a liquid includes a determination portion that executes a first determination process of determining whether or not a first error occurs in which replacement of the print head or replacement of a hardware coupled to the print head is required and a second determination process of determining whether or not a second error occurs in which neither the replacement of the print head nor the replacement of the hardware coupled to the print head is required, and a light emitting portion that emits light according to a result of determination in the determination portion.

There is provided a liquid discharge apparatus including: an amplifier circuit that outputs an amplified modulated signal by driving a transistor; a demodulation circuit that includes an inductance element and outputs the driving signal, in which the inductance element includes a first side portion provided with a first terminal, a second side portion positioned facing the first side portion and provided with the second terminal, a third side portion intersecting with the first side portion and the second side portion, a lead member coupled to the first terminal and the second terminal, and a shortest distance between the transistor and the third side portion is equal to or shorter than a shortest distance between the transistor and the first side portion, and is equal to or shorter than a shortest distance between the transistor and the second side portion.

There is provided a maintenance method of a head unit including a first nozzle array and a second nozzle array, the method including: in a first period, supplying a first driving signal having a first waveform to one first driving element corresponding to one first nozzle belonging to the first nozzle array to eject the liquid from one first nozzle; and supplying a second driving signal having a second waveform to one second driving element corresponding to one second nozzle belonging to the second nozzle array to eject the liquid from one second nozzle; and in a second period, supplying a third driving signal having a third waveform to the one first driving element to eject the liquid from the one first nozzle; and supplying a fourth driving signal having a fourth waveform to the one second driving element to eject the liquid from the one second nozzle.

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.