In accordance with an embodiment, an inkjet head comprises a head section, a clock signal generator, a drive controller and a current measurement section. The head section applies a drive voltage to a wall surface of an ink chamber and ejects ink from the ink chamber. The clock signal generatorsends a clock signal to the head section. The drive controller stops the clock signal sent to the head section, and applies a predetermined drive voltage to the head section. The current measurement section measures a current flowing to the head section while the drive controller stops the clock signal sent to the head section.

A drive circuit that drives a piezoelectric device including a drive signal selection control circuit which controls supply of the drive signal to the piezoelectric element, the drive circuit including a drive signal output circuit that outputs the drive signal, a power supply voltage signal output circuit that outputs a power supply voltage signal, and a power supply voltage control circuit that controls supply of the power supply voltage signal to the drive signal selection control circuit, in which the drive signal output circuit includes a modulation circuit, an amplification circuit, a demodulation circuit, a feedback circuit, and a discharge circuit, a first wiring electrically couples the drive signal selection control circuit and the power supply voltage control circuit to each other, and the discharge circuit is electrically coupled to a second wiring through which the drive signal output from the demodulation circuit propagates, through the feedback circuit.

A memory circuit for a print component including a plurality of I/O pads, including an analog pad, to connect to a plurality of signals paths which communicate operating signals to the print component, and a memory component to store memory values associated with the print component. A control circuit to, in response to identifying a sequence of operating signals representing a memory read, provide a first analog signal on the analog pad in parallel with a second analog signal from the print component to provide an analog electrical value on the analog pad representing stored memory values selected by the memory read.

A firing circuit for a thermal inkjet-printing nozzle includes a heater resistor and a switch. The heater resistor heats ink to cause the ink to be ejected from the nozzle. The heater resistor has a first end and a second end, the second end connected to a ground. The switch controls activation of the heater resistor. The switch has a first end connected to a voltage source and a second end connected to the first end of the heater resistor. The switch operates in a constant current mode, such that an at least substantially constant current flows through the heater resistor upon activation.

A print element substrate, comprising a plurality of heating elements, a plurality of detection elements, each configured to detect a temperature of a corresponding heating element, a first current generation unit, a second current generation unit, and a signal output unit, wherein one of the first and second current generation units supplies a current to a first detection element, the other supplies a current to a second detection element, and the signal output unit outputs a signal according to a potential difference between one terminal of the first detection element on a side where a potential variation occurs upon supply of the current and one terminal of the second detection element on a side where a potential variation occurs upon supply of the current.

One example provides a fluidic die including a nozzle layer disposed on a substrate, the nozzle layer having an upper surface opposite the substrate and including a plurality of nozzles formed therein, each nozzle including a fluid chamber and a nozzle orifice extending through the nozzle layer from the upper surface to the fluid chamber. A conductive trace is exposed to the upper surface of the nozzle layer and extends proximate to a portion of the nozzle orifices, an impedance of the conductive trace indicative of a surface condition of the upper surface of the nozzle layer.

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.

A fluid ejection device includes a number of primitives, each receiving a same set of addresses and including a number of ejection chambers, each corresponding to a different address of the set of addresses and including a drive bubble formation mechanism and a drive bubble detect (DBD) mechanism. Input logic receives nozzle column data groups (NCG), each NCG including fire pulse groups (FPG), each FPG including DBD data having an enable value or disable value, and ejection data bits, each ejection data bit corresponding to a different one of the primitives. For each FPG of each NCG, activation logic identifies the FPG as a DBD FPG when the DBD data has the enable value and activates in each primitive the drive bubble formation mechanism and the DBD mechanism identified by the DBD FPG to perform a DBD measurement.

A print head that includes a drive element to be driven when a drive signal is supplied to the drive element and that ejects liquid by the driving of the drive element includes an ejecting module including the drive element and a nozzle from which the liquid is ejected, and a current detecting circuit that detects a drive current generated due to propagation of the drive signal. The current detecting circuit includes a current detector that detects the drive current as a current detection signal, and a processor that controls an operation of the current detecting circuit according to the current detection signal.

A liquid ejecting apparatus includes a driven element that is driven by a drive signal; an ejection head that ejects a liquid when the driven element is driven; a drive circuit that outputs the drive signal, the drive circuit including an amplifier circuit that includes a first transistor and amplifies, based on an amplification voltage and through an operation of the first transistor, a base drive signal based on which the drive signal is generated; and a leakage current detection circuit that detects a leakage current in the drive circuit. The leakage current detection circuit is electrically connected to the first transistor included in the amplifier circuit to which the amplification voltage is supplied.