Circuit arrangement for powering control circuitry and driving an inductive load from a single DC source

A circuit arrangement for driving an inductive load having first and second windings which are electrically connected and magnetically coupled to form an autotransformer having a common terminal which is common to electrically connected ends of the windings and first and second terminals electrically connected to the respective windings remotely from said ends, in said arrangement:

• a. means is provided for electrically connecting the common terminal to a first pole of a DC power source;
• b. the first terminal is electrically connected through a first switch means to means for electrical connectiion to a second pole of the DC power source, said first switch means having a control electrode for effecting switching between conductive and non-conductive states;
• c. the second terminal is electrically connected through a second switch means to means for electrical connectiion to the second pole of the DC power source, said second switch means having a control electrode for effecting switching between conductive and non-conductive states;
• d. the control electrodes are operatively coupled to a control means for alternately effecting switching of the first and second switching means into the respective conductive states;
• e. the control means includes first and second power terminals for connection to a source of DC power;
• f. the first power terminal is electrically connected through first and second rectifiers to the first and second terminals, respectively, of the autotransformer, said first rectifier providing current to said first power terminal when the second switching means is conducting and said second rectifier providing current to said first power terminal when the first switching means is conducting;
• and
• g. the second power terminal is electrically connected to a second pole of the DC power source.