Points electronic reversing of BLDC and built-in Hall sensor reversing, the right chart is assembly diagram. The forth is integrated drive circuits, which can easy to control the speed ,etc, the latter need to driver to make up the servo system, so it be called brushless servo motor.

BLDC structure of electronic the reversing structure is simple, suitable for undemanding speed accuracy ,which need long continuous working application,such as fan ,water pump,etc.