A liquid ejection head unit includes an ejection unit that ejects a liquid, a first wire configured to supply a fixed potential used for driving the ejection unit, a second wire configured to transmit a pulse signal that defines an ejection timing of the liquid in the ejection unit, a first counter whose count value changes based on a potential change in the first wire, a second counter whose count value changes based on a potential change in the second wire, and an ejection restriction unit that restricts an ejection operation of the liquid in the ejection unit according to a count value of the first counter and a count value of the second counter.

An integrated circuit is disclosed. The integrated circuit includes an actuator to eject a fluid in response to a fire signal. The integrated circuit also includes a monitor circuit set by the fire signal to block the fire signal to the actuator circuit after a selected duration.

A fluidic die including fluid chambers, each including an electrode exposed to an interior of the fluid chamber and each having a corresponding fluid actuator operating at a first voltage level. Monitoring circuitry, operating at a second voltage level lower than the first voltage level, includes a select transistor and a pulldown transistor for each fluid chamber to selectively couple to the electrode, at least the select transistor being a high voltage tolerant transistor to operate at the second voltage in a normal operating condition and having a breakdown voltage level greater than the first voltage level to prevent a fault current from flowing into the select transistor from the electrode in a fault condition if the fluid actuator short-circuits to the electrode.

An integrated circuit to drive a number of fluid actuation devices, comprising a circuit configured to have a memory access state which can be set to one of an enabled state and disabled state. The integrated circuit to include a fluid actuation circuit to transmit selection information for a fluid actuation device, the selection information comprising a data state bit. The integrated circuit to include a memory cell array, configured so that each memory cell is accessible by the memory access state being enabled, and the data state bit being set.

In one example in accordance with the present disclosure, a fluidic die is described. The fluidic die includes an array of firing subassemblies grouped into zones. Each firing subassembly includes 1) a firing chamber, 2) a fluid actuator, and 3) a sensor plate. The fluidic die also includes a measurement device per zone to measure a voltage indicative of an impedance within a selected firing chamber. The fluidic die includes a selector per firing subassembly to couple a selected sensor plate to the measurement device. A selector is adjacent a respective firing subassembly and a distance between the selector and the measurement device is different as compared to other selectors.

Example implementations relate to current leakage testing of a fluid ejection die. For example, a fluid ejection die may include plurality of nozzles, each nozzle among the plurality of nozzles including a nozzle sensor and a fluid ejector. The plurality of nozzle sensors may comprise a first subset and a second subset, each nozzle sensor among the plurality of nozzle sensors of the first subset may be electrically coupled to a first control line by a respective switch among a first group of switches, and each nozzle sensor among the plurality of nozzle sensors of the second subset may be electrically coupled to a second control line by a respective switch among a second group of switches. The fluid ejection die may include a control circuit to perform a current leakage test of the plurality of nozzles using the first control line and the second control line.

An integrated circuit to drive a number of fluid actuation devices, comprising a circuit configured to have a memory access state which can be set to one of an enabled state and disabled state. The integrated circuit to include a fluid actuation circuit to transmit selection information for a fluid actuation device, the selection information comprising a data state bit. The integrated circuit to include a memory cell array, configured so that each memory cell is accessible by the memory access state being enabled, and the data state bit being set.

A communicating print component a print head comprising a number of memory bits and a single lane analog bus conductively coupling the number of memory bits to a pad located on the exterior of the print head. The pad is to transmit an electrical signal from the number of memory bits, wherein the electrical signal indicates a combination of all selected bits of the number of memory bits.

In some examples, a controller includes an interface to receive an indication based on an electrical current through a device, and a processor to send control data to the device to operate the device, detect a measurement based on the indication that is responsive to an operation of the device according to the control data, and determine whether an issue exists in the device responsive to determining whether the measurement satisfies an expected property based on the control data.

A fluidic die includes a plurality of fluid chambers, each fluid chamber including an electrode exposed to an interior of the fluid chamber and having a corresponding fluid actuator operating a high voltage separated from the fluid chamber and electrode by an insulating material, and monitoring circuitry, operating at a low voltage, to monitor a condition of each fluid chamber. For each fluid chamber the monitoring circuitry includes a sense node and a conductor connecting the electrode to the sense node, the conductor having a geometry to form at least one region of higher current density relative to remaining portions of the conductor, the at least one region of higher current density to fail and create an open to protect the low-voltage monitoring circuitry in response to a fault current caused by a short circuit of the high voltage fluid actuator to the electrode.