Hi all can ı make design 1/10 or 1/20 microstep resulation with stspin820 stepper motor driver of st microelectronic by manipulate vref input and R current sensing resistance

[ASayd.1]

I wanna step motor driver by stpin820 device without 1/2 ....1/256 for example 1/20 e.t.c manupilate resistance for ıc current sensing and vref input thanks

[Cristiana SCARAMEL · Accepted solution]

Hello @ASayd.1​,

no it is not possible implement microstep resolution different from the one settable trough the MODEx inputs.

In theory you could set the full step mode and generate the proper reference waveforms as the reference voltage (rectified sine-wave voltages). The two references, one for each full-bridge, must have a phase delay of 90°. The "limit" of STPIN820 is due to the single voltage reference (REF pin) for both full bridge.

I can suggest as alternative the STSPIN840 that have two separated reference voltage pins for the PWM current control circuitry. With this device you have the complete flexibility to manage the desired microstepping mode.

I hope this post can help you; if so, consider to mark it as best answer by clicking the label "Select as Best".