THERMAL INK JET PRINTING HEAD SYSTEM EQUIPPED WITH MULTI- OUTPUT DRIVER CIRCUIT FOR SUPPLYING POWER TO HEATING ELEMENT AND METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide a multi-output driver circuit for a thermal ink jet printing head simplified in a structure so as to dispense with one amplifier circuit per each power output transistor. SOLUTION: A monolithically integrated multi-output power driver circuit 66 is formed as a semiconductor integrated circuit to be connected to the respective heating elements in a printing head 50 and has the power MOS transistor connected to the respective heating elements. A reference circuit is operationally connected to the respective gates of the power MOS transistor and has a reference transistor equipped with gates and a reference amplifier receiving a reference voltage and current supply source as input. The output of the amplifier is operationally connected to the gates of the power output transistor and the gates of the reference transistor. The reference amplifier adjusts the reference transistor directly and adjusts the power MOS transistor by matching.