The P315 stepper motor driver from Astrosyn is a low cost bipolar unit measuring only 86 mm x 55 mm x 20 mm. Seven selectable microstepping resolutions offer a range of motor increments, with up to 12,800 steps per revolution. The unit is simple to set up, helped by details of the switch settings printed on the front of the case. Internal jumpers enable the input frequency to be easily optimised.
Supply voltage is in the range 15 - 40 Vdc, and output current is adjustable from 0.1 - 1.5 A. The unit uses an inaudible chopping frequency of 20 kHz.
Other features include overcurrent, overvoltage and short circuit protection, and automatic idle current reduction. Mixed decay current control reduces motor overheating. Input signals are optically isolated and TTL compatible.