A memory circuit for a print component including a plurality of I/O pads, including an analog pad, to connect to a plurality of signal paths which communicate operating signals to the print component. The memory circuit includes a controllable selector connected in line with one of the signal paths via the I/O pads, the selector controllable to disconnect the corresponding signal path to the print component, and a memory component to store memory values associated with the print component. A control circuit, in response to a sequence of operating signals received by the I/O pads representing a memory read, to operate the controllable selector to disconnect the signal path to the print component to block the memory read of the print component, and provide an analog signal to the analog pad to provide an analog electrical value at the analog pad representing stored memory values selected by the memory read.

A liquid discharge apparatus is provided that includes a transport unit configured to transport a medium, a discharge unit configured to discharge a liquid onto the medium, a housing including therein the discharge unit, a humidifying unit configured to humidify an interior of the housing, and a humidity detection unit configured to detect a humidity. When the humidity detection unit detected a humidity less than a lower limit value (one example of a first predetermined value) (positive determination in step S12), the interior of the housing is humidified by the humidifying unit during transport by the transport unit or during discharge by the discharge unit (step S16).

An integrated circuit includes thermal tracking logic, control logic, and an output interface. The thermal tracking logic determines a temperature of a fluid ejection die. The control logic defines an emulated parameter of the fluid ejection die as a function of the temperature of the fluid ejection die. The output interface outputs the emulated parameter to a printer system based on the function and the temperature of the fluid ejection die.

A liquid discharge head includes a nozzle from which a liquid is dischargeable in a liquid discharge direction, an individual chamber communicating with the nozzle, a common chamber configured to store the liquid to be supplied to the individual chamber, a pressure generator configured to apply pressure to the liquid in the individual chamber, a holder holding the pressure generator, a first temperature detector adjacent to the common chamber, the first temperature detector configured to detect temperature proximate to the common chamber, and a second temperature detector held by the holder, the second temperature detector configured to detect temperature of the holder.

A liquid injection device includes a driving signal correction circuit correcting a reference driving signal based on a temperature detected by a temperature sensor. The driving signal correction circuit includes a first correction circuit that corrects injection pulses excluding a liquid drop injection speed-controlling injection pulse when the temperature detected by the temperature sensor is lower than or equal to a predetermined reference temperature, and a second correction circuit that corrects all of the injection pulses when the temperature detected by the temperature sensor is higher than the predetermined reference temperature.

A liquid ejecting head unit includes an ejecting surface in which nozzles for ejecting a liquid are formed, and a first and a second circuit substrates for ejecting the liquid from the nozzles, in which a planar shape of the ejecting surface includes a first, a second and a third portions. A center line parallel to a long side of a rectangle of a minimum area surrounding the ejecting surface passes the first portion but not the second and third portions. The second and third portions are arranged adjacently to the first portion interposed therebetween. The first circuit substrate is positioned in the first and second portions. The second circuit substrate is positioned in at least one of the first and third portions.

In order to keep possible local temperature differences in a liquid ejection head small to allow stable liquid ejection performance to be achieved, temperatures in a plurality of heating areas in a liquid ejection head are discretely controlled using heating elements and temperature detection elements.

A printer includes an ink ejecting section that ejects ink from a nozzle, an ink circulation path including an ink flow path through which the ink can be supplied to an ink ejecting section and an ink return path through which the ink supplied to the ink ejecting section is returned, a warming device including a temperature control module provided in the ink circulation path, where the warming device can heat the ink in the temperature control module, and a feed pump that can flow the ink in the ink circulation path, wherein the flow rate of the ink, in the ink circulation path, heated by the warming device is adjusted.

Ambient temperature based flow rates can in an example include a setting a flow rate of ink to a printhead mounted in a carriage based on an ambient temperature associated with the printhead, measuring a flow rate of ink to the printhead, and causing a decrease in a velocity of the carriage in response to the flow rate of ink satisfying the threshold flow rate.

Provided is a liquid ejection head including: a plurality of recording element substrates including energy generating elements that generate ejection energy for ejecting liquid from ejection orifices; a first support member that supports the plurality of recording element substrates such that the recording element substrates are arranged in one or more lines on a main surface of the first support member; and a second support member that supports the first support member on a surface opposite to the main surface. A first thermal resistance concerning an in-plane direction parallel to the main surface, of a region between the recording element substrates in the first support member is higher than a second thermal resistance concerning a thickness direction of the second support member, of a projection region that overlaps with each recording element substrate in the second support member.