Patent attributes
An apparatus for controlling a temperature of an ink-jet printhead includes a heater driving field effect transistor (FET) connected to a heater, the heater driving FET for applying a heater voltage to the heater according to a waveform input to a gate of the heater driving FET, a current sensor for converting current flowing between a drain and a source of the heater driving FET into a voltage and for outputting the voltage, a comparator for comparing the voltage output from the current sensor with a predetermined reference voltage, a warming control signal generator for generating a warming control signal in a form of a pulse string, and a switching unit for receiving an output signal from the comparator and the warming control signal, and for outputting the warming control signal according to a level of the output signal from the comparator to the gate of the heater driving FET.
