features:<br />1. 100%  and high quality.<br />2. bipolar constant current chopper<br />3. high-speed optocoupler signal isolation input<br />4. electrical input signal is ttl compatible<br />5. stationary current is automatically reduced by half<br />6. suitable for any small-and-medium automatic equipment with cnc controller， such as x-y-z tables， labeling hines， laser cutters， engraving hines， and pick-place devices.<br /><br />specifications:<br />1. supply voltage: 9~40vdc<br />2. input voltage: dc 12 ~ 48v<br />3. operating temperature: -10 to 45 ?c<br />4. storage temperature: -40 to 70 ?c<br />5. max drive current: 4a<br />6. chopping frequency: 20khz<br /><br />package included:<br />1 x 4a tb6600 stepper motor driver controller