We are using 4 DRV2605Ls to drive 4 LRA motors in open loop mode. In final assembly, motors are located in a wrist band. This is why we would like to run a diagnostic routine to examine motors against short, open or stuck rotor situations.
Since DIAG_RESULT bit only works either in closed loop or calibration mode, we have decided to run auto calibration routine to examine motors. Auto cal params are fine tuned to get more accurate results.
If there is problem with motor, it always returns failure that is 100% reliable. However, in some cases, although motors are okay, auto cal reports failure through DIAG_RESULT bit. I could say 9% it returns false failures. We wanted to use other outputs to judge the result of the auto calibration procedure but found that it does not matter if result reported as failed, false failed, or passed, BEMF_GAIN, A_CAL_COMP, and A_CAL_BEMF register values are getting pretty much the same or very close values. The only way left is to run diagnostic multiple times to mark a motor as okay if auto cal passes at least one time in X amount of iterations.
So the question is: is there another way to diagnose motors? We are also open for any suggestions to diagnose LRA motors in open loop mode.
