DM860 Fully Digital Stepper Drive Manual V1.0
7
Selecting Supply Voltage
The power MOSFETS inside the DM860 can actually operate within +24 ~ +110VDC, including power input
fluctuation and back EMF voltage generated by motor coils during motor shaft deceleration. Higher supply voltage can
increase motor torque at higher speeds, thus helpful for avoiding losing steps. However, higher voltage may cause
bigger motor vibration at lower speed, and it may also cause over-voltage protection or even driver damage. Therefore,
it is suggested to choose only sufficiently high supply voltage for intended applications, and it is suggested to use
power supplies with theoretical output voltage of +20 ~ +68VDC, leaving room for power fluctuation and back-EMF.
7. Selecting Microstep Resolution and Driver Output Current
This driver uses an 8-bit DIP switch to set microstep resolution, and motor operating current, as shown below:
Microstep Resolution Selection
Microstep resolution is set by SW5, 6, 7, 8 of the DIP switch as shown in the following table:
Microstep Steps/rev.(for 1.8°motor) SW5 SW6 SW7 SW8
2 400 ON ON ON ON
4 800 OFF ON ON ON
8 1600 ON OFF ON ON
16 3200 OFF OFF ON ON
32 6400 ON ON OFF ON
64 12800 OFF ON OFF ON
128 25600 ON OFF OFF ON
256 51200 OFF OFF OFF ON
5 1000 ON ON ON OFF
10 2000 OFF ON ON OFF
20 4000 ON OFF ON OFF
25 5000 OFF OFF ON OFF
40 8000 ON ON OFF OFF
50 10000 OFF ON OFF OFF
100 20000 ON OFF OFF OFF
200 40000 OFF OFF OFF OFF
Current Settings
For a given motor, higher driver current will make the motor to output more torque, but at the same time causes more
heating in the motor and driver. Therefore, output current is generally set to be such that the motor will not overheat for
long time operation.