BLDC motor from a floppy drive

[tbj]

Hi.

I salvaged this BLDC motor from a floppy drive and it doesn't appear to have a hall sensor. I'm wondering if the axial inductor is used to sense rotor position instead?



Any ideas?

Cheers

[SeanB]

There will be 3 hall sensors there, probably buried under the steel backing plate. The axial inductor around the edge is there for the rotational velocity feedback loop only, and the tacho pulse.