E-TEA3718DP Datasheet, PDF (19/26 Pages) STMicroelectronics – Stepper motor driver

6
Application notes
Application notes
6.1
Motor selection
Some stepper motors are not designed for continuous operation at maximum current. As the
circuit drives a constant current through the motor, its temperature might increase
excessively both at low and high speed operation.
Also, some stepper motors have such high core losses that they are not suited for switch
mode current regulation.
6.2
Unused inputs
Unused inputs should be connected to proper voltage levels in order to get the highest noise
immunity.
6.3
Interference
As the circuit operates with switch mode current regulation, interference generation
problems might arise in some applications. A good measure might then be to decouple the
circuit with a 15 nF ceramic capacitor, located near the package between power
line VS and ground. The ground lead between R_S, C_C and circuit GND should be kept as
short as possible. This applies also to the lead between the sensing resistor R_S and point S.
See Section 4: Functional blocks.
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