TMC5160 DATASHEET (Rev. 1.08 / 2018-NOV-19)
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7 stealthChop™
stealthChop is an extremely quiet mode of operation for stepper motors. It is based on a
voltage mode PWM. In case of standstill and at low velocities, the motor is absolutely
noiseless. Thus, stealthChop operated stepper motor applications are very suitable for
indoor or home use. The motor operates absolutely free of vibration at low velocities.
With stealthChop, the motor current is applied by driving a certain effective voltage into the coil,
using a voltage mode PWM. With the enhanced stealthChop2, the driver automatically adapts to the
application for best performance. No more configurations are required. Optional configuration allows
for tuning the setting in special cases, or for storing initial values for the automatic adaptation
algorithm. For high velocity drives spreadCycle should be considered in combination with stealthChop.
Figure 7.1 Motor coil sine wave current with stealthChop (measured with current probe)
7.1 Automatic Tuning
stealthChop2 integrates an automatic tuning procedure (AT), which adapts the most important
operating parameters to the motor automatically. This way, stealthChop2 allows high motor dynamics
and supports powering down the motor to very low currents. Just two steps have to be respected by
the motion controller for best results: Start with the motor in standstill, but powered with nominal
run current (AT#1). Move the motor at a medium velocity, e.g. as part of a homing procedure (AT#2).
Figure 7.2 shows the tuning procedure.
Border conditions for AT#1 and AT#2 are shown in the following table:
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