Zum ElDef Bit
7.2 General problems when getting started
Q: What is the meaning of ElDef?
A: The ElDef flag (‘Electrical Defect’) is the logical ORing of the OVC1 and OVC2 flags. OVC1 is set to
one in case of an overcurrent (coil short) or open load condition (selected coil current is not reached)
for coil A. OVC2 is the equivalent for coil B.
Q: What could be the reason for ElDef / OVC1 / OVC2 being set to one?
A: There are a number of possible causes:
• Motor not connected (􀃆 open load)
• Connected motor has shorted coils (􀃆 overcurrent) or broken coils (􀃆 open load)
• Motor coils connected to the wrong device pins
• Selected coil current can not be reached (􀃆 open load) due to high coil impedance or low
supply voltage. Solution: Select a lower coil run/hold current or rise the supply voltage.
Generally: the calculated voltage required to reach a desired coil current at a given coil
resistance (V = I • R) must be significantly lower than actual supply voltage due to the coil
inductivity.

Auf Deutsch: Die Ströme dürfen nicht zu gross Dimensioniert werden. Der IC will den Strom immer begrenzen(regeln nicht schalten). -> Grosser Motor = grosser Strom, IC läuft; kleiner Motor, Stom wird nicht erreicht -> "Elektrischer Defekt" -> ElDef Bit wird gesetzt. -> Haltestrom Ihold und Irun (Laufstrom) anpassen.