Patent ID: 7175248
Filing Date: 2007-02-13
Classification: B41J

Abstract:
1. A fluid ejection device comprising: a plurality of fluid ejecting elements, each fluid ejecting element coupled between a shared supply path at a supply voltage and a shared return path at a reference voltage and to a separate control line, and controllable to conduct electrical current from the shared supply path to the shared return path in response to a fire signal received via the separate control line, wherein up to all fluid ejecting elements of a group of the plurality of fluid ejecting elements are configured to conduct during a time period, with each conducting fluid ejecting element having a corresponding fluid ejecting voltage when conducting; and a feedback circuit configured to provide a feedback voltage substantially equal to an average of corresponding fluid ejecting voltages at the fluid ejecting elements that are conducting, the feedback circuit comprising: a plurality of supply sense switches each corresponding to a different one of the fluid ejecting elements and coupled be a supply sense line and the shared supply path; and a plurality of reference sense switches each corresponding to a different one of the fluid ejecting elements and coupled between a reference sense line and the shared return path, wherein each supply sense switch and reference sense switch respectively ties the supply sense line to the shared supply path and the reference sense line to the shared return path in response to the fire signal received via the separate control line.