| 摘要 |
PROBLEM TO BE SOLVED: To prevent rise in supply voltage in kickback without fail. SOLUTION: When any of the connecting ends Uout, Vout, and Wout of a motor is brought into high voltage, any of transistors Q10, Q11, and Q12 is turned on. When any of the connecting ends Uout, Vout, and Wout (Uout in the case of the figure) is brought into low voltage in this state, a transistor Q14 is turned on and the output of a flip flop FF1 is brought into LOW. As a result, the corresponding upstream power transistor is turned on and the connecting end Uout at low voltage is connected with supply voltage. Thus, rise in supply voltage is prevented. The output of the flip flop FF1 is transmitted to flip flops FF2 and FF3. During a period for which the inverted Q output of the flip flops 2 and 3 is at LOW, the downstream power transistor connected to the power transistor which is turned on by the above operation is turned off. Thus, the production of feedthrough current is prevented. |
