Thick film print head structure and control circuit

Abstract

A thick-film thermal printhead (FIG. 11) and a variety of implementation approaches for controlling such a printhead. The conductive lead at each end of the heater element is switched to either the power supply (Vhd) or ground, depending on the corresponding nib data bit with the advantage of eliminating leakage current completely. Thermal printhead control is based on the sequential exclusive-OR (XOR) logic operation applied to the shifted-in nib data bit stream. The XOR function may be within the driver IC, the raster data processing FPGA (Field Programming Gate Array), or in a lookup table in the memory block of a main processor system. A new driver IC is disclosed in which the outputs are SPDT (Single-Pole-Double-Throw) switches, and the built-in XOR gates are configured to act in the pass-through mode, so that the new driver IC may be used as a traditional driver IC.

Dependencies are inferred from the claim text.