Provided is a printing apparatus configured to perform printing on a print medium by using a printing unit, the printing apparatus including: a power storage unit capable of storing power fed from an external power source connected via a USB cable; a measurement unit capable of measuring time based on power from the power storage unit; a control unit configured to execute predetermined processing based on a measurement result of the measurement unit; and a restriction unit capable of restricting power fed from the power storage unit. In a period in which power feed from the external power source is stopped, the restriction unit restricts feeding of power to units other than at least the measurement unit depending on a power storage amount of the power storage unit, and the measurement unit continues the measurement.

A recording device includes a facing section disposed facing a recording section and a movement unit configured to move the recording section by receiving power from a motor. A control section sets an origin position of the recording section in a movement direction based on a position of the recording section when a signal change of a linear encoder disappears in a state where a signal change of a rotary encoder exists while the recording section is being lowered toward the facing section or a position of the recording section when the signal change of the linear encoder appears in a state where the signal change of the rotary encoder exists while the recording section is being raised from a state of being placed on the facing section.

A liquid ejection system includes a first head unit and a second head unit. The first head unit includes a first determining circuit that determines whether a first power supply voltage is normal, a first drive circuit that outputs a first drive signal based on the first power supply voltage, and a first ejecting head that ejects liquid The second head unit includes a second determining circuit that determines whether a second power supply voltage is normal, a second drive circuit that outputs a second drive signal based on the second power supply voltage, and a second ejecting head that ejects liquid When the first determining circuit determines that the first power supply voltage is not normal, or when the second determining circuit determines that the second power supply voltage is not normal, the first ejecting head and the second ejecting head stop ejecting the liquid.

A method of driving a liquid ejecting apparatus including a piezoelectric element, and a pressure chamber. The method includes: generating a plurality of pairs of first drive signals and second drive signals, the first drive signals include electrical potential-changing elements that change in electrical potential, and the second drive signals that include electrical potential-maintained elements that maintain fixed electrical potentials, and detecting, as a plurality of residual vibration signals for the plurality of pairs, variations in electromotive force of the piezoelectric element according to variations in residual pressure that is applied to liquid in the pressure chamber after every supplying the electrical potential-changing element and the electrical potential-maintained element to the piezoelectric element for the plurality of the pairs, and identifying a first deformation property of the piezoelectric element based on the plurality of residual vibration signals for the plurality of pairs.

There is provided a liquid droplet ejecting apparatus including: a conveyor configured to convey a print medium in a conveying direction; a line head having a plurality of nozzles which is disposed side by side in the conveying direction and a crossing direction crossing the conveying direction and each of which is configured to eject a liquid droplet to the print medium; and a controller configured to increase an ejection velocity of the liquid droplet by an upstream nozzle, of the plurality of nozzles, located upstream in the conveying direction of a downstream nozzle being a part of the plurality of nozzles, to be higher than the ejection velocity of the liquid droplet by the downstream nozzle, or to delay an ejection timing of the liquid droplet by the upstream nozzle.

A power supply control apparatus comprises a first power supply supplying power to a controller and a second power supply supplying power to an operation unit and a power controller. The operation unit receives an operation for switching the first power supply on and off. The power controller is operable to turn on the first power supply according to the signal from a timer or the operation by the operation unit, and to turn off the first power supply according to a state of the controller. The controller, upon at least either of the operation by the operation unit or the signal from the timer, performs a setting to the timer of a time at which to turn on the power from the first power supply or a time at which to turn off the power from the first power supply.

Disclosed herein is a secure controller for a replaceable print apparatus component, circuitry for association with a replaceable print apparatus component, and a replaceable print apparatus component. The secure controller is to perform secure communication with a host apparatus via a serial data bus. The controller further is to, in response to a first command from the host apparatus, execute a first operation associated with the first command, wherein the controller is to consume power within a first range during execution of the first operation. The controller also is to, in response to a second command from the host apparatus specifying a dwell time, transition to a low-power state and consume power within a second range in the low-power state for a duration based on the dwell time, the second range being below and spaced apart from the first range.

An evaluation control portion, in which the evaluation control portion causes the detection circuit to detect, as first residual vibration, residual vibration caused by continuously performing jetting driving in which the piezoelectric element is driven with a vibration pulse for generating, at the vibration plate, vibration larger than vibration of the vibration plate caused by non-jetting driving in which the piezoelectric element is driven with a minute vibration pulse for not jetting an ink from the nozzle, causes the detection circuit to detect, as second residual vibration, residual vibration caused by continuously driving the piezoelectric element in order of the non-jetting driving and the jetting driving, and evaluates a variation in a jetting characteristic of the nozzle between a case where the jetting driving is continuous and a case where the jetting driving is not continuous based on the first residual vibration and the second residual vibration.

A print head includes a pressure chamber whose volume changes according to a drive signal, a nozzle communicating with the pressure chamber and configured to allow a liquid to be discharged, a piezoelectric element configured to output a residual vibration signal corresponding to a residual vibration caused by a change in the volume of the pressure chamber, a residual vibration detection circuit configured to receive the residual vibration signal and output a residual vibration detection signal corresponding to the residual vibration signal, and a first switch circuit configured to switch whether to supply the residual vibration signal to the residual vibration detection circuit. The first switch circuit is an N-channel type transistor.

An image forming apparatus includes a head unit, and a switching power supply. The head unit is configured to eject ink. The switching power supply is configured to supply electric power to the head unit. Further, the head unit includes an actuator unit to eject ink; and the switching power supply operates with a switching frequency different from a natural vibration frequency of the actuator unit.