Patent ID: 6817690
Filing Date: 2004-11-16
Classification: B41J

Abstract:
A printing apparatus for printing on a printing medium by moving a printhead including a plurality of printing elements, comprising:input means for inputting print data transmitted from an external device; a carriage, in which the printhead is mounted and a voltage control unit that supplies a controlled voltage for driving the plurality of printing elements of the printhead is provided, for moving the printhead; counting means for counting a number of printing elements of the printhead to be driven based on the print data input by said input means; evaluation means for evaluating an extent of a load of a succeeding print cycle to be applied to the printhead based on a count result by said counting means; and control means for inputting an evaluation signal indicating an evaluation result by said evaluation means to the voltage control unit, and controlling the voltage based on the evaluation signals, wherein the voltage control unit is a DC/DC converter, and wherein the DC/DC converter includes: a differential circuit that detects a signal change in the evaluation signal; and an adder circuit that adds an output from the differential circuit to a reference voltage of the DC/DC converter.