Patent ID: 7198355

Claim:
A printhead assembly, comprising: at least one printead module comprising at least two printhead integrated circuits, each of which has nozzles formed therein for delivering printing fluid onto the surface of print media, a support member supporting and carrying the printing fluid for the at least two printhead integrated circuits, and an electrical connector for connecting electrical signals to the at least two printhead integrated circuits; a plurality of longitudinally extending electrical conductors arranged to provide power from a power supply to the at least two printhead integrated circuits via the electrical connector; a casing comprising a support frame on which the at least one printhead module and at least one mounting element are removably held, the at least one mounting element having formed therein a plurality of recessed channels for receiving and removably mounting individual ones of the plurality of electrical conductors; and a drive circuitry unit for removable mounting to the mounting element to control the operation of the at least two printhead integrated circuits, the drive circuitry unit having contacts for electrical connection to the electrical connector, input contacts for receiving print data from an external source or an adjacent drive circuitry unit controlling the printhead integrated circuits of an adjacent printhead module, and at least one print engine controller integrated circuit for processing the print data applicable to a predetermined number of the at least two printhead integrated circuits; wherein the drive circuitry unit is selected from a range of drive circuitry units, each having a different number of print engine controller integrated circuits such that the ratio of print engine controller integrated circuits to printhead integrated circuits can be varied to change the print speed of the printhead assembly.