Device configuration

UM1685

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DocID025458 Rev 2

In conclusion the suggested configuration for the demonstration boards is following:



VCC value = 15 V.



UVLO threshold = 11 V (10 V on boot).



Gate current = 64 mA.



Controlled current time = 1

s.



Dead time = 250 ns.



Blanking time = 500 ns.



Turn OFF boost time = disabled.

3.4

Overcurrent and stall detection thresholds

The overcurrent protection and the stall detection (EVAL6480H only) are implemented by

measuring the drain-source voltage of the MOSFETs, hence their value is a voltage and not

a current.

The protection thresholds are set according to the voltage drop caused by the target

parameter increases with temperature).

During the preliminary stages of evaluation, the max. value of 1000 mV can be set for both

protections. The default value of 281.25 mV has a good probability to trigger the overcurrent

alarm.

Warning:

Important - it is strongly discouraged to disable the

overcurrent shutdown. It may result in critical failures.

3.5

Speed profile

The max. speed parameter is the maximum speed the motor will run. By default, it is about

1000 step/s. That means, if you send a command to run at 2000 step/s, the motor speed is

limited at 1000 step/s.

This is an important safety feature in the final application, but not necessarily useful to

evaluate the device performances. Setting the parameter to high values (e.g. 6000 step/s)

allows evaluating the maximum speed which can be achieved by the application under test

through the speed tracking command (Run), but it probably limits the possibility to use

positioning commands (Move, GoTo, etc.).

The Full-step speed parameter indicates the speed at which the system switches from

microstepping to full step operation.

In voltage mode driving devices (EVAL6480H), it is always recommended to operate in

microstepping and not to switch to the full step. Hence, this parameter should be greater

than the maximum speed.