| 摘要 |
PURPOSE:To enable the output terminals of a driving device to be reduced by halves, and enable a detection current value to be controlled to come to a desired current value by arranging the mutual jointing points of two output transistors which are to-tem-pole-jointed to each other, and current detecting resistors between the mutual jointing points of the output transistors and output terminals, and by detecting bidirectional current independently via the output terminals. CONSTITUTION:By setting CR 24-26 between mutual jointing points 37-39 with three sets of totem-pole-jointed transistors(Tr) 31, 32, and 33, 34, and 35, 36, and output terminals 9-11, bidirectional current flowing to star-connection stator coils U, V, W respectively can be separately detected. For example, both end potentials of the current detecting resistor(CR)24 are detected by differential circuits 92, 95. The input of the output of the differential circuits 92, 93, to comparators 81, 82 is provided. besides, the input of desired current values ADUH, ADUL, to the comparators is provided. The output of the comparators 81, 82 is applied to the bases of the Trs 31, 32. Accordingly, the output terminals of a driving gear can be reduced by halves, and two sets of the Trs can be controlled with constant current. |
