A liquid jetting apparatus includes: a liquid jetting head having individual channels, first and second common channels connected to the individual channels, the individual channels having nozzles respectively; a pump which circulates liquid inside the liquid jetting head; and a controller. The controller is configured to: reduce a unit circulation amount of the liquid in stages as standby time becomes longer, the unit circulation amount being a circulation amount of the liquid per unit time by the pump, the standby time being a length of time during which a standby state is continued, the standby state being a state in which the liquid jetting head is ready without jetting the liquid; and in a case of shifting the liquid jetting head from the standby state to a jetting operation, determine a type of recovery operations in accordance with the standby time.

A print head control circuit controls an operation of a print head that includes a nozzle plate and has a self-diagnosis function performed based on signals input from a first coupling point, a second coupling point, a third coupling point, and a fourth coupling point. The print head control circuit includes a first cable that includes a first power voltage signal propagation wiring for propagating a first power voltage signal, and a second cable that includes a first diagnosis signal propagation wiring for propagating a first diagnosis signal input to the first coupling point. A shortest distance between the nozzle plate and the first cable is longer than a shortest distance between the nozzle plate and the second cable.

A drop ejector array device includes a first plurality and a second plurality of drop ejectors that are alternatingly disposed along an array direction on the substrate surface. A voltage input terminal and a current return terminal are disposed on the substrate surface. A first power bus line connects the first plurality to the voltage input terminal. A second power bus line connects the second plurality to the voltage input terminal. The second power bus line is electrically connected to the first power bus line by a primary power bus connector line. A first current return bus line connects the first plurality to the current return terminal. A second current return bus line connects the second plurality to the current return terminal. The second current return bus line is electrically connected to the first current return bus line by a primary current return bus connector line.

A head unit control circuit controls a head unit. The head unit includes an ejector, a determination circuit, and an ejection limit circuit. The ejector includes a displaceable piezoelectric element for controlling the liquid ejection. The piezoelectric element is displaced by changing a drive signal potential. The determination circuit determines whether the piezoelectric element has a predetermined electrical storage capability. The ejection limit circuit stops the drive signal to limit the ejection of the liquid based on the determination. The head unit control circuit includes: a first terminal that outputs an instruction signal instructing the head unit to execute the determination; a second terminal that outputs the drive signal; and a third terminal that is between the first terminal and the second terminal. The third terminal has a smaller potential change width than the second terminal when the ejecting section ejects the liquid.

A liquid-droplet ejecting apparatus includes: N nozzles; N driving elements; M power supply circuits that create a driving signal to be selectively supplied to the N driving elements; and N selecting circuits that selectively connect one of the M power supply circuits to a corresponding one of the N driving elements. The N driving elements are connected to the M power supply circuits in a first combination until a particular condition is satisfied. The first combination is a combination between the M power supply circuits and an M driving element groups, into which the N driving elements are divided based on a voltage of the supplied driving signal. The N driving elements are connected to the M power supply circuits in a second combination after the particular condition is satisfied. The second combination is another combination between the M driving element groups and the M power supply circuits.

An intermediate transfer body is efficiently heated, and thus, transfer properties of an image and durability of the intermediate transfer body are ensured. A heating unit heats the intermediate transfer body by using a plurality of heating sources which are positioned by being shifted, with respect to a rotation direction of the intermediate transfer body. The plurality of heating sources includes a first heating source and a second heating source. A degree of heating the intermediate transfer body by the second heating source is greater than a degree of heating the intermediate transfer body by the first heating source. The second heating source is positioned on an upstream side, with respect to the rotation direction of the intermediate transfer body, from the first heating source.

Heating is conducted sequentially by dividing a heating operation into first heating control and second heating control consuming higher electric power than that in the first heating control.

A second power is lower than a first power to be supplied during a printing operation. In a case where the second power is supplied to a print head through a cable as a drive power for the nozzles in the print head, the change in voltage of the second power is detected. The nozzles in the nozzle arrays are driven on an array-by-array basis with the second power on the basis of a control signal, and whether there is breakage in the cable is detected on the basis of the result of the detection of the change in voltage of the second power during the driving of the nozzles.

In a print element substrate: if an amount of a voltage drop when the number of print elements driven simultaneously in a state in which the predetermined voltage is applied with respect to one print element array is largest is set as an amount of a voltage drop of the print element array, and a sum of amounts of voltage drops of the print element arrays assigned to one group is set as an amount of a voltage drop of the group, a difference between a largest value and a smallest value of the amounts of the voltage drops of the M groups is smaller than a largest value of the amounts of the voltage drops of the N print element arrays.

An inkjet recording apparatus has a head, a first board, and a second board. The head has a plurality of nozzles and a plurality of driving elements. The first board includes a control circuit and a sensing circuit unit. The second board includes a driving voltage generator and a driver circuit. The driver circuit makes ink ejected. The driving voltage generator and the driver circuit are connected together via a first power supply line. The sensing circuit unit is connected to the first power supply line and outputs a first sensing signal. Based on the first sensing signal, the control circuit senses an abnormality in power supply on the second board.