New Stepper Drive Boards Ready
Posted by retromaster on January 26, 2010
I’ve finished building the new bipolar stepper driver. I’ve tested it, and it works, with a big speed/torque increase. There are two boards, a parallel port breakout board (with optical isolation) and the actual stepper driver board that accepts step and direction pulses. As I’ve mentioned in previous posts, I’ve gotten rid of the current sensing resistors and gone for a fixed frequency PWM chopper scheme instead. This seems to be sufficient for the motors I currently use, but I am definitely interested in trying out more elaborate driving schemes with more capable (higher current, lower voltage) motors in the future.
Both boards are designed to be mounted in the plastic enclosures as shown in the photo. There will be a 4-pin round connector for each axis and a power led on the front side of the box. On the back side will be the parallel port and power connectors as well as a power switch. I might also put some ventilation holes somewhere on the box but I am not sure that they will be necessary. Cutting the plastic plates for the sides of the enclosure will be the first order of business for the new drives.