L6470 vibration

[srg0016]

Posted on November 16, 2012 at 22:38

Hello! My question is in follows:

I got L6470 working, but not in a desirable way. Stepper motor vibrates in all speed range. It seems that phase current form distorted as shown in Fig. 15 (Section 7.3, p. 35 of datasheet), because motor pulses each time when electrical position corresponds the full step. Low Speed Optimization option really reduces this effect at low speed but it still remain in all range causing the vibration. Is it normal operation state or I just haven't adjust driver properly? What I have to do in this case? Hope, somebody will help me..

[Enrico Poli]

Posted on December 04, 2012 at 16:13

Hello,

The vibration of the motor could be related to different causes:- Device is working in full-step cause the FS_SPEED threshold: the voltage mode doesn't give the best when used in full-step, you should set the full-step speed value above the maximum speed, in this way the device always uses the microstepping.- Motor resonances: stepper motors could have strong resonance issues when they are driven without nay load. I always suggest to add a small load on the motor shaft (e.g. a little disc) in order to damp a bit the resonances.Kind RegardsEnrico