MakerBot BotStep17 REVE

thingiverse

The BotStep17 connects to the MightyBoard for controlling MakerBot Replicator's stepper motors, designed by Harry Mulliken. This is part of The MakerBot Replicator, available at http://www.thingiverse.com/thing:18813. Key features include an Allegro A4928 controller chip, a max motor voltage VBB of 28V and a max logic voltage VDD of 5.5V. Max power dissipation without heatsink is 2W. Default Vref voltage is VDD x 0.267 ± 2%, with default motor current being Vref/2.16 ± 10%. The Rosc is GND, mixed decay mode. MS1 and MS2 control microstep resolution and excitation mode, ranging from Full Step to Sixteenth Step. Refer Table 1 for the Microstep Resolution Truth Table. Current is fixed by internal resistors (33K to VDD, 12K to GND), which can be changed on pin VR. For maximum current, Imax = Vref/(8x0.27). A 0 ohm resister fixes the connections (fixed).