KERN & SOHN VFS 2T1 Addendum - Manual (Page 13)

EPM205 - Technical reference - Rev. A Page 13
Advanced Printing Systems
4. STEPPER MOTOR
4.1. Stepper motor Timing
The paper feed pitch for stepper motor is 2 steps for one dot-line (0.125 mm). For good print quality it is
advised to keep the current into the windings between two successive dot-lines.
The timing diagram is then as follows:
PHASE 1
PHASE 2
PHASE 3
DOTLINE 1 2 3
PHASE 4
STEP
There are four different positions for the stepper motor. The driving is bipolar and can be achieved with
circuits like Rohm BA6845FS, Sanyo LB1836 or LB1838 or Hitachi HA13421. Please refer to the IC’s data
sheet for further information. It is recommended not to exceed 0.2v like voltage drop in the stepper motor
driver circuit.
Coil resistance is 12 Ω, rated current is 300 mA (5V) per phase while feeding at 10mm/s.
In case of high voltage or continuous printing application, contact APS for current application circuitry.