| 摘要 |
PROBLEM TO BE SOLVED: To reduce effects of radiation noise generated from a thermal head, a thermal head control part and a cable which connects them. SOLUTION: A system clock of 50 MHz is multiplied by two, thereby generating a clock of 100 MHz. Clocks of a plurality of frequencies are generated by dividing this clock. A data clock signal which changes to a plurality of frequencies is generated by sequentially selecting these clocks. Data turning on/off from a thermal head driving data generating part 14 is transferred by the data clock signal which changes to the plurality of frequencies, and is held at a position corresponding to each of heating resistors R1-Rn by a shift register 41. Each of the heating resistors R1-Rn is electrified by the on/off data held by the shift register 41. The energy of noise is dispersed because the frequency of the data clock signal changes within a single-strobe period of time, so that the effects of radiated noise can be reduced. COPYRIGHT: (C)2009,JPO&INPIT |
