Abstract: According to an example, a method for performing maintenance routines in a plurality of actuators comprises firing a set of actuators at different energies, determining turn on energy values for the set of actuators based on measurements measured via chamber sensors associated with the set of actuators at the different energies, determining turn on energy differences for the set of actuators based on the turn on energy values determined for the set of actuators and threshold turn on energy values associated with the set of actuators, and performing maintenance routines corresponding to the determined turn on energy differences.

Abstract: In some examples, a fluid ejection die includes a plurality of nozzles arranged in a plurality of nozzle columns, the plurality of nozzle columns distributed across a width of the fluid ejection die in a staggered manner, wherein nozzles of each respective nozzle column of the plurality of nozzle columns are spaced apart along a length of the fluid ejection die, wherein the plurality of nozzle columns includes a first pair of neighboring nozzle columns that are spaced by a first distance across the width. The plurality of nozzle columns includes a second pair of neighboring nozzle columns that are spaced by a second distance across the width, the second distance being larger than the first distance.

Abstract: In one example in accordance with the present disclosure, a fluidic die is described. The fluidic die includes a substrate and fluid actuators, the fluid actuators being disposed on the substrate. The fluidic die also includes a bond pad region defined on the substrate. The bond pad region includes a high aspect ratio power delivery bond pad with multiple bonding sites and a high aspect ratio power return bond pad with multiple bonding sites.

Abstract: In some examples, a fluidic die includes fluidic actuators, switches, and electrically conductive lines in an electrically conductive layer of the fluidic die. The electrically conductive lines electrically connect the switches to respective actuators. A first dimension of a first electrically conductive line is different from a second dimension of a second electrically conductive line to match a first resistance of the first electrically conductive line having a first length to a second resistance of the second electrically conductive line having a second length different from the first length.

Abstract: In some examples, a fluidic die includes an arrangement of fluidic elements to dispense a fluid, each fluidic element of the fluidic elements including a fluidic actuator and a fluid chamber. An array of fluid feed holes is arranged in a plurality of dimensions to communicate the fluid with the fluidic elements, where each of multiple fluid feed holes along a first dimension of the plurality of dimensions is distinct from multiple fluid feed holes along a second dimension of the plurality of dimensions. The fluidic die includes first circuit elements operable at a first power supply voltage, the first circuit elements interspersed in regions between the fluidic elements along different axes of the fluidic die.

Abstract: In some examples, a fluidic die includes an arrangement of fluidic elements to dispense a fluid, where each fluidic element of the fluidic elements includes a fluidic actuator and a fluid chamber. The fluidic die includes an array of fluid feed holes in a plurality of dimensions to communicate the fluid with the fluidic elements, where each of multiple fluid feed holes along a first dimension of the plurality of dimensions is distinct from multiple fluid feed holes along a second dimension of the plurality of dimensions. The fluidic die includes circuit elements interspersed in regions between the fluidic elements along different axes of the fluidic die, where each circuit element of the circuit elements includes an active device. The fluidic elements and the circuit elements are formed on a common substrate.

Abstract: According to examples, an apparatus may include a substrate having a fluid recirculation channel and a membrane adjacent to the fluid recirculation channel, in which the membrane is portion of the substrate having a smaller thickness than other portions of the substrate. The apparatus may also include a component layer, in which a fluid ejection chamber may be formed in the component layer. The fluid ejection chamber may include a nozzle and fluid may be received into the fluid ejection chamber through an inlet port and recirculated to the fluid recirculation channel through an outlet port. The apparatus may further include active circuit elements formed on the membrane, in which the active circuit elements may control ejection of fluid from the fluid ejection chamber through the nozzle.

Abstract: In some examples, a fluid ejection die includes a plurality of nozzles arranged in a plurality of nozzle columns, the plurality of nozzle columns distributed across a width of the fluid ejection die in a staggered manner, wherein nozzles of each respective nozzle column of the plurality of nozzle columns are spaced apart along a length of the fluid ejection die, wherein the plurality of nozzle columns includes a first pair of neighboring nozzle columns that are spaced by a first distance across the width. The plurality of nozzle columns includes a second pair of neighboring nozzle columns that are spaced by a second distance across the width, the second distance being larger than the first distance.

Abstract: An example fluid ejection device comprises a plurality of distinct fluid channels. Each fluid channel comprises a distinct fluid inlet to the ejection device. A subset of the plurality of distinct fluid channels comprises fluid recirculating fluid channels, and the remaining fluid channels comprising non-recirculating fluid channels.

Abstract: Examples include a fluid ejection device. The fluid ejection device includes a fluid ejection die with a die length and a die width, the fluid ejection die being coupled with a support structure having a fluid supply channel therethrough. The fluid ejection die includes a plurality of nozzles arranged in columns at die length positions along the die length and die width positions along the die width such that only one nozzle is positioned at each die length position. A fluid ejection chamber is coupled with each respective nozzle of the plurality of nozzles, and fluid feed hole fluidically coupled with the fluid supply channel and each respective ejection chamber.

Abstract: In some examples, a fluid ejection die includes a plurality of nozzles arranged in a plurality of nozzle columns, the plurality of nozzle columns distributed across a width of the fluid ejection die in a staggered manner, wherein nozzles of each respective nozzle column of the plurality of nozzle columns are spaced apart along a length of the fluid ejection die, wherein the plurality of nozzle columns includes a first pair of neighboring nozzle columns that are spaced by a first distance across the width. The plurality of nozzle columns includes a second pair of neighboring nozzle columns that are spaced by a second distance across the width, the second distance being larger than the first distance.

Abstract: In one example in accordance with the present disclosure, an additive manufacturing module is described. The additive manufacturing module includes an agent distributor to selectively distribute a fabrication agent onto layers of build material. The agent distributor includes at least one fluidic ejection die. Each fluidic ejection die includes a plurality of nozzles arranged along a die length and a die width, the plurality of nozzles arranged such that, for each set of neighboring nozzles, a respective subset of each set of neighboring nozzles are positioned at different die width positions along the width of the fluidic ejection die. The fluidic ejection die also includes, for each respective nozzle of the plurality of nozzles, a respective ejection chamber fluidically coupled to the respective nozzle and for each respective ejection chamber, at least one respective fluid feed hole fluidically coupled to the respective ejection chamber.

Abstract: One example of a fluid ejection system includes a plurality of fluid ejection devices, a corresponding plurality of indicators, an operator interface, and a controller. Each indicator is on a corresponding fluid ejection device. The operator interface is to select a fluid ejection device. The controller is to turn on the corresponding indicator for the selected fluid ejection device.

Abstract: Examples include a fluidic die. The fluidic die comprises an array of field effect transistors. Connecting members electrically connect at least some of the field effect transistors of the array of field effect transistors, and the field effect transistors of the array are arranged into respective sets of field effect transistors. The fluidic die further comprises a first fluid actuator connected to a first set of field effect transistors having a first number of field effect transistors. The die includes a second fluid actuator connected to a second respective set of field effect transistors having a second number of field effect transistors that is different than the first number of field effect transistors.

Abstract: In one example in accordance with the present disclosure, a fluidic die is described. The fluidic die includes a substrate and fluid actuators, the fluid actuators being disposed on the substrate. The fluidic die also includes a bond pad region defined on the substrate. The bond pad region includes a high aspect ratio power delivery bond pad with multiple bonding sites and a high aspect ratio power return bond pad with multiple bonding sites.

Abstract: One example provides a fluidic die including a nozzle layer disposed on a substrate, the nozzle layer having an upper surface opposite the substrate and including a plurality of nozzles formed therein, each nozzle including a fluid chamber and a nozzle orifice extending through the nozzle layer from the upper surface to the fluid chamber. A conductive trace is exposed to the upper surface of the nozzle layer and extends proximate to a portion of the nozzle orifices, an impedance of the conductive trace indicative of a surface condition of the upper surface of the nozzle layer.

Abstract: One example provides a fluidic die including a semiconductor substrate, and a nozzle layer disposed on the substrate, the nozzle layer having a top surface opposite the substrate and including a nozzle formed therein, the nozzle including a fluid chamber disposed below the top surface and a nozzle orifice extending through the nozzle layer from the top surface to the fluid chamber, the fluid chamber to hold fluid, and the nozzle to eject fluid drops from the fluid chamber via the nozzle orifice. An electrode is disposed in contact with the nozzle layer about a perimeter of the nozzle orifice, the electrode to carry an electrical charge to adjust movement of electrically charged components of the fluid.

Abstract: Examples include a fluid ejection device. The fluid ejection device includes a fluid ejection die with a die length and a die width, the fluid ejection die being coupled with a support structure having a fluid supply channel therethrough. The fluid ejection die includes a plurality of nozzles arranged in columns at die length positions along the die length and die width positions along the die width such that only one nozzle is positioned at each die length position. A fluid ejection chamber is coupled with each respective nozzle of the plurality of nozzles, and fluid feed hole fluidically coupled with the fluid supply channel and each respective ejection chamber.

Abstract: The fluid ejection device includes a plurality of nozzles and a plurality of ejection chambers that includes a respective ejection chamber fluidically coupled to a respective nozzle. A plurality of inlet passages are fluidically coupled to the ejection chambers and input fluid to the ejection chambers at a first pressure. A plurality of outlet passages are fluidically coupled to the ejection chambers and output fluid from the ejection chambers at a second pressure that is less than the first pressure. Fluid circulates through the ejection chambers based on the pressure difference between the first and second pressure. The fluid ejection device also includes at least one micropump fluidically coupled to at least one ejection chamber to pump fluid through the at least one ejection chamber.

Abstract: 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.