TMC603A Datasheet, PDF (25/44 Pages) TRINAMIC Motion Control GmbH & Co. KG. – Three phase motor driver with BLDC back EMF commutation hallFX™ and current sensing

TMC603A DATA SHEET (V. 1.15 / 2009-Nov-19)
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Turn the motor up to a minimum velocity, where you safely get correct hallFX™ signals. Since rotation
of the motor can not be measured during this phase, the motor needs to be current controlled, with a
current which in every case is high enough to turn the mechanical load. Current control can be done
by feedback control, or by adapting the duty cycle to the motor characteristics. Further, the minimum
starting speed and acceleration needs to be set matching the application. For sample code, please
see www.trinamic.com. Upon reaching the threshold for hallFX™ operation, a valid hall signal
becomes available and allows checking success of the starting phase. The turning direction of the
start-up sequence automatically determines the direction of motor operation with hallFX™. You can
check velocity and direction, as soon as valid hallFX™ signals are available.
When you experience commutation sequence errors during motor operation, probably motor velocity
has dropped below the lower threshold. In this case, the motor could be restarted in forward control
mode, or you could switch to forward control mode on the fly.
Copyright © 2009 TRINAMIC Motion Control GmbH & Co. KG