MTD2005F pdf data: http://www.chinaicmart.com/series-MTD/MTD2005F.html
FEATURES
Constant-current chopping function
(Frequency fixed, separate-oscillation)
2-phase input
(ENA input is useful for half step drive)
Selectable slow/fast current decay for improved micro stepping
A noise cancel function is provided
(No externally attached filter needed)Protection for penetration currentBuilt-in thermal alarmBuilt-in flywheel diodes