3.3PAPER FEED CHARACTERISTICS

zThe bipolar chopper driving method should be used for driving.

zAny type of design for the drive circuit other than the example described in Section 3.4.1 may affect the standard function of the printer.

zPaper is fed in the forward direction when the motor shaft is rotating anticlockwise as seen from the motor gear side.

zThe motor is driven by a 2-2 phase excitation method and feeds paper by 0.125 mm (equivalent to a single dot pitch) every one step of the motor drive signal.

zTo prevent deterioration in print quality due to backlash of the paper feed system, the motor should be rotated 16 steps in the reverse direction, then 16 steps in the normal direction during initialization.

zDuring paper feed, the motor should be driven at 1760 pps through the motor acceleration control. As exceptions, when using the LTPF347 under 0°C to 10°C in temperature, drive it at 1200 pps or less. At dynamic division driving, do not use it more than 1200 pps.

zDuring printing, the motor drive frequency should be adjusted so that the head activation pulse width does not exceed the motor step time. (For details, see CHAPTER 5 DRIVE METHOD.)

zIf the motor is continuously driven at less than 450 pps continuously, noise and/or paper sticking may occur.

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