Stepper Motor Driver

This stepper motor driver is simple without compromising versatility. It has a conventional computer interface, an optional on-board clock generator, and integrated motor control and driver stages. The board can drive dual-stator motors, i.e., motors with two bipolar, or four unipolar, phases. Maximum current per phase is 2A. The circuit diagram of Fig. 2 shows that the circuit is designed around chip set L297-L298 from SGS. The block diagram of the L297 is given in Fig. 1. This IC generates control signals for a dual-stator motor, and enables selecting direction of travel and full or half-step operation by appro- priate programming of its TLL- compatible inputs. One full or half step is performed on the trailing edge of the signal applied to the clock input (CLK). When the enable input, E, is held logic low, the motor is not energized, so that the spindle can be rotated freely. Driv- 1 A !NM B C INH2 D STEPPER MOTOR DRIVER HALF/FULL STEP RESET DIRECTION CLOCK HOME ENABLE CON TROL...