CIRCUITRY FOR SUPPLYING A CONTROLLED SIGNAL TO A DRIVE SYSTEM.

摘要

Circuitry (163) that provides alternating current to a load (104) from a unipolar power supply having a current source (333) that controls the amount of current applied to said load. A first switch (301) and a second switch (302) in the circuitry are connected between the load and the current source (333) and allow current to flow from the current source (333) to the load (104) in a first direction responsive to the first switch and the second switch being closed. A third switch (303) and a fourth switch (304) are connected between the load and the current source (333) and allow current to flow from said current source (333) to the load in a second direction responsive to the third switch and the fourth switch being closed.