Circuit configuration for affecting the step frequency in the

Abstract

Bipolarity current-activated windings of powerful stepping motors for high step frequencies are to be indexed such that for each load condition the optimum motor torque is attained. The circuit configuration according to the invention comprises for this purpose chopped power output stages ((1, 2)) which are each activated by direction-dependent logic phase signals (PH12, PH34) of a signal generator (3) for the current feed into the motor windings of the stepping motor drive. Via a chopper pulse weighting circuit (4.2) winding indexing signals are supplied to the signal generator (3). To the chopper pulse weighting circuit (1,2) are supplied logic chopper signals (CH12, CH34) which can be tapped at the power output stages ((1, 2)) at the output side, and a device (7,14) connected to the chopper pulse weighting circuit (4.2) ensures that always only that chopper signal (CH12 CH34) is conducted to the chopper pulse weighting circuit (4.2), which is decisive for the next winding switch-over.