Powerstep01 power supply manangement

[Sams]

Hi Guys,

I'm using external 3.3V to supply permanently the powerstep01 logic and would like to supply VS (24V) only when I need the motor (I put the schematic in attachment).

The problem is the logic does not work without VS.

Everything works fine if VS is supplied permanently. But if we supply first 3.3V and the 24V a bit later (when I need the motor), the motor does not run. I have already tried to clear UVLO error flag through CmdGetstatus command after connecting VS but it didn't help. A reset by setting low then resetting high the reset pin didn't help neither.

Thanks in advance for your help

[CTapp.1]

Is the way you are managing the power supply pins compatible with the restrictions in Section 7.19 (Supply management and internal voltage regulators) of the datasheet?

[Sams]

Thanks for you reply @CTapp.1 

I think so, I have already checked the datasheet several times but I could not find a response to my problem. I have shared my schematic diagram in my post, I would appreciate any review.