Driving circuit capable of maintaining heat equilibrium of a print head nozzle

A driving circuit for driving an ink jet print head of a printing device to print data onto a medium, the driving circuit having a plurality of nozzles and corresponding hearing elements, the driving circuit being capable of individually providing energy to the heating elements such that the nozzles are capable of jetting ink drops onto the medium, the driving circuit comprising:

• a latch for latching and storing data;
• and
• a driving signal generator for providing a first driving signal and a second driving signal to heat a first set of the heating elements and a second set of the heating elements respectively, the driving signal generator comprising:
• a multiplexer having at least one selection unit for providing the first driving signal and at least one selection unit for providing the second driving signal both according to data received from the latch;
• wherein when the first set of the heating elements receives the first driving signal and simultaneously the second set of the heating elements receives the second driving signal, the first set of the heating elements will be heated to a level above a threshold so as to cause corresponding nozzles to jet ink drops onto the medium, and the second set of the heating elements will be heated to a level below the threshold so as to avoid corresponding nozzles from jetting ink drops onto the medium.