how to use hard disk spindle motors

[mrmmani22]

hi every one
i m need to use hard disk spindle motor for my proj bcos it gives constant high rpm like 5400 or 7200rpm. i have some dumb harddisk. pls tell me how to run them. is it possible to use normal power transisotr to drive those motors. samsung harddisk motor comes with 4 wires and seagate harddisk motor comes with 3 wires. if i give a voltage to any of those pin the motor just jerks and stops.

 

[Nigel Goodwin]

Presumably they are DC brushless motors?, and the electronics required to make them work will be on the PCB. I've just taken a number of Maxtor drives to pieces, and they have four surface-mount power transistors feeding the motor windings.

 

[maazbuzdar]

Hi every1....!!!
I've a maxtor 40GB HD's spindle motor(4 terminals). when i supplied 12volt & ground to its 4 terminals one by one....it jerked only. i know there must be a circuit running it properly but how can i make such a circuit (as the one in HD)...???
Also tell me how to identify the four terminals of motor..?
plz if anyone has some idea share it with me....

 

[Nigel Goodwin]

Try reading the previous post - you can't just supply power to it.

 

[Frankco]

Hi mrmmani22,

You can send a timed pulse to each of the windings using a 555 timer and a 8-bit shift register. It's not very efficient to turn it this way but it will work.

To find the common wire test the ohms across each of the three windings. One wire will give you a slight lower value. That's the center tap.

There are some new chips out on the market with emf back sensing that should work nicely. The benefit of them is that you have better control in speeding up and slowing down the drive. The problem is that I haven't found a source were you don't have to purchase a 1000 of them.

For the circut using the 555 timer:
(Howto) Walz a Hard Drive Spindle Motor | Let's Make Robots!

 

[Chippie]

Presumably they are DC brushless motors?, and the electronics required to make them work will be on the PCB.

In the R/C world, we have brushless 3 phase motors that are self starting...

The three phases are provided by sets of P and N channel mosfets driven by a microcontroller( usually Atmel )...To start the motor the micro energises 2 of the phases and measures the third for back emf...once started the phases are energised in turn and the emf from the offline phase is used to determine how fast the motor spins when compared to the r/c signal it receives...

Well summat along those lines..you get the gist...

Something like that could be cobbled together to spin up the hdd motor...Writing the code for the micro is the hardest part...

Have a look here...:
BLDC controller - RC Groups

 

[Nigel Goodwin]

In the R/C world, we have brushless 3 phase motors that are self starting...

Hardly 'self-starting'

You then go on to describe the processor based electronics that starts it and runs it.

 

[Chippie]

Hardly 'self-starting'

You then go on to describe the processor based electronics that starts it and runs it.

Awww.....stop nitpicking..

 

[be80be]

It's not hard at all to run a harddrive motor the 4 wire is easy to do never tried a 3 wire
the thing is it spins up to speed so you can't start at full speed i used 4 half bridges and switched from one to the next with a delay between each step

 

[Frankco]

Hard drive spindle motor - timing

Hi Burt,

What do you for the delay?

Frank

 

[be80be]

It was a 10ms delay I was going to make a clock with one and didn't want to use but the motor

 

[Frankco]

Hi Burt,

What chips or circuit did you use for the 10ms delay to drive the half bridges?

 

[Nigel Goodwin]

Hi Burt,

What chips or circuit did you use for the 10ms delay to drive the half bridges?

I would imagine he used a micro-controller to do it all?, it's the obvious and easiest way.

 

[maazbuzdar]

Well...i think now i have some clues to start work on that motor
It's my very first chance to deal with a spindle motor....
Thanks to everyone...

 

[Frankco]

Thanks Nigel. Nice tutorials on your web pages.

It's been a while since I played around with electronics. I'm getting back into it again. We're about the same age, (I'm a year older), and it was back when I was in my late 20s and 30s since the last time I put circuits together. So, I've got a bit of catching up to do
Respectfully bowing to my Sensei
Frank

 

[Nigel Goodwin]

It's been a while since I played around with electronics. I'm getting back into it again. We're about the same age, (I'm a year older)

So you're 22 then?

 

[Frankco]

Feel like it anyway, at least until I see someone who is 22

 

[be80be]

When i go to the shop today i'll post what code i used if i can find I made a board with a 12f675 to run the motor

 

[Frankco]

Thanks Burt.

I'm keeping an eye on your eBay store. I'm sure you'll have some stuff that will come in handy for projects as I go along.

Frank

 

[be80be]

Here a picture of the board still looking for code I think the code and circuit was on my
old harddrive that went bad **broken link removed**
What you do is set the common of the hard drive motor to + vdd and that gives you 3 wire
that you hook to Y1 Y2 Y3 set the bridge EN pin to low and switch A1 A2 A3 on and off in a row the motor will spin I used a I think 10mS delay to start the motor then after it was spining the code changed the delay to 5ms