Four inch print head assembly

Abstract

An apparatus and method allow for assembly of a print head apparatus for an ink jet printer. The apparatus comprises control capability for controlling the flow of fluid to the droplet generator and for controlling transfer of data to the droplet charging and collecting element. The control capability for controlling transfer of data to the droplet charging and collecting element is a motherboard containing various elements. The motherboard includes a microcontroller and fiber optics for receiving data and control signals and providing the signals to an input buffer. A RAM provides data memory, and a latch and shift register latch and shift the data from the RAM. A high voltage driver receive data from the latch and shift register. A control state machine communicates with the microcontroller, for handling generation of all control signals for the input buffer, the RAM, and the latch and shift register. Finally, opto couplers buffer the low voltage circuitry from high voltage circuitry in the print head apparatus. The print head apparatus is capable of providing diagnostic functions, and is self-contained in a field-replaceable housing.