STMicro's L6470 (a.k.a "dSPIN") is a 3A, 8-45V bipolar stepper motor driver. It has built-in overcurrent detection, undervoltage detection, overtemperature detection, stall detection, a 5-bit ADC, and a switch input that can be used for either user jog control or as a hard stop function. As if that weren't enough, it also features microstepping support (up to 128 microsteps per full step) and PWM drive voltage limiting. Project description, more information and ordering can be found at https://www.sparkfun.com/products/10859 Datasheet: http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Robotics/dSPIN.pdf Example Sketch: http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Robotics/dsPin_example.zip Product Video: http://youtu.be/3Ve1dsLf364?t=1m10s