Hi guys,
this is just to thank you all.
I've got the SG3525 part. My motor was running using Logic-level rated mosfet. The IRF740 did not produced any result. Motor not running but it make noise like a whistle. Pretty normal, but no turning of the shaft.
Once substituted with a P30N06 logic level mosfet, then voila. Motor running and SG3525 able to regulate the speed up and down.

Thanks again.