US Patent 7175248 Fluid ejection device with feedback circuit

A fluid ejection device includes a plurality of fluid ejecting elements, each fluid ejecting element controllable to conduct electrical current between a supply voltage and a reference voltage. Up to all fluid ejecting elements of a group of the plurality of fluid ejecting elements are configured to conduct during a time period. Each conducting fluid ejecting element has a corresponding fluid ejecting voltage when conducting. A feedback circuit is configured to provide a feedback voltage substantially equal to an average of corresponding fluid ejecting voltages at the fluid ejecting elements that are conducting.