| 摘要 |
The present invention is a switch mode current control circuit which is particulary useful with step motors. The circuit has a first transistor, a coil and a first resistor connected in a series with a first voltage source. An optocoupler having a light emitting diode and a second transistor therein has the light emitting diode connected across the first resistor and the second transistor is connected across the base emitter junction of the first transistor. A second resistor is connected to the base of the first transistor and to the second voltage source. A diode is connected across the coil.
|
