Hard dsk motor

[GreekPIC]

I dismantled a dead hard disk and I can't figure out the main motor. Is it a stepper? It has 4 contacts so I thought bipolar stepper. However if it was so, the two pairs should be isolated to eachother which is not the case. I tried to apply voltage in a sequence, it acts kind of like a low resolution stepper (~90

[GreekPIC]

Anyone?

Oh, BTW I meant disk, not dsk...

Maybe that's why I get no answers:

-Hard dsk? What is that? :)

Nikolas

[gsmaster]

check this http://home.cc.umanitoba.ca/~umparekh/hard_drive_clock.html

[audioguru]

I like the Stair Lights. The cat seems to be wondering how the light turn on by themselves.
I better not let my wifey see the video or I'll be working on my stairs for weeks. ;D

[GreekPIC]

check this http://home.cc.umanitoba.ca/~umparekh/hard_drive_clock.html

Well thanks but this doesn't really answer my question. This guy powers the HD and it spins up with it's own controller. But how can I use the motor alone with other electronics?

Nikolas

[ante]

The hard drive motor is not a stepper, however it is electronically commutated. The circuit is included in the drives electronics and varies between different manufacturers.

[Morpheus4893]

I have also been attempting to use hard disk motors for some time, have found the driver chip on the old board, got the datasheet for the chip & they are not easy to wire up - the driver IC seems to use some kind of serial interface to the main drive controller, But the motors themselves are virtually the same as the motor in a DC brushless fan, might even be able to use a driver chip from one of those... The possibilities are endless...