A plurality of sub control circuits are connected to respective ones of a plurality of head units. One of the plurality of sub control circuits is connected to a main control circuit so as to perform communication. The plurality of sub control circuits include a first control circuit and a second control circuit. The second control circuit is connected to the first control circuit in series so as to perform communication. The first control circuit is configured to: receive first data, the first data including a first parameter and a second parameter, the first parameter corresponding to the first control circuit, the second parameter corresponding to the second control circuit; and transmit the first data to the second control circuit. The second control circuit is configured to: receive the first data from the first control circuit; and delete the first parameter from the first data.

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.

An integrated circuit to drive a plurality of fluid actuation devices includes a plurality of contact pads, a plurality of pulldown devices, and control logic. The plurality of contact pads include a first contact pad and a second contact pad. Each of the pulldown devices is electrically coupled to a corresponding contact pad. The control logic enables at least a portion of the pulldown devices in response to both a logic low signal on the first contact pad and a logic low signal on the second contact pad.

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 printer for printing on a print medium as said print medium advances through a print zone, the printer including a number of print heads extending over the print zone, each print head including at least one nozzle array wherein at least two adjacent nozzle arrays overlap forming at least one stitching zone in the overlap region; and a printer controller for generating a sequence of nozzle firing commands for each nozzle array to selectively deposit droplets of print fluid on said print medium from said nozzle arrays in accordance with an image to be printed, wherein the printer controller further applies masks having decorrelated patterns to said sequence of firing commands for at least those overlapping nozzles of the nozzle arrays coinciding with the at least one stitching zone to obtain a predetermined optical parameter of the printed image in the stitching zone, irrespective of an offset between two adjacent nozzle arrays.

In a droplet ejection control apparatus according to the invention, a judgment section judges, taking a dot position that is assigned by a predetermined nozzle (incorrect ejection position) as a reference, whether or not a printing state is such that a second proximity dot lands earlier than a first proximity dot. A changing section changes an ejection state, when the ejection state is judged to be such that the second proximity dot lands earlier than the first proximity dot, to another ejection state in which the first proximity dot lands earlier than the second proximity dot.

An ink printing process employs per-nozzle droplet volume measurement and processing software that plans droplet combinations to reach specific aggregate ink fills per target region, guaranteeing compliance with minimum and maximum ink fills set by specification. In various embodiments, different droplet combinations are produced through different printhead/substrate scan offsets, offsets between printheads, the use of different nozzle drive waveforms, and/or other techniques. These combinations can be based on repeated, rapid droplet measurements that develop understandings for each nozzle of means and spreads for expected droplet volume, velocity and trajectory, with combinations of droplets being planned based on these statistical parameters. Optionally, random fill variation can be introduced so as to mitigate Mura effects in a finished display device. The disclosed techniques have many possible applications.

An inkjet print head includes an ejection unit having a liquid chamber for holding an amount of liquid, a electromechanical transducer operatively coupled to the liquid chamber for generating a pressure wave in the amount of liquid and a nozzle in fluid communication with the liquid chamber for enabling a droplet of the amount of liquid to be ejected through the nozzle. A method for detecting an operating state of the ejection unit includes the consecutive steps of actuating the electromechanical transducer to generate a pressure wave in the liquid; actuating the electromechanical transducer to suppress a residual pressure wave in the liquid; sensing an amplitude of the residual pressure wave in the liquid; and based on the result of the sensing step determining that the ejection unit is (i) in an operative state if the amplitude of the residual pressure wave is below a threshold or (ii) in a malfunctioning state if the amplitude of the residual pressure wave is above the threshold.

Priming printheads can, in various examples, include moving a movable member of a printhead from a first position to a second position, measuring a response time of the movable member to move from the first position to the second position, and identifying the printhead as primed.

A correction data setting apparatus, which sets correction data in a memory for storing the correction data for correcting a pulse width of a drive pulse signal applied to each actuator corresponding to each nozzle of an inkjet head, comprises a generation section which sequentially generates a channel No. for individually identifying each nozzle; an output section which outputs a parameter required for arithmetic which represents a characteristic of a correction amount with respect to an arrangement direction of the nozzles; an arithmetic section which executes the arithmetic using the parameter output from the output section to calculate the correction amount for each channel No. generated from the generation section; a conversion section converts the correction amount calculated for each channel No. by the arithmetic section to the correction data; and a setting section sets the correction data obtained for each channel No. by the conversion section in the memory.