Driving six steppers with one driver and multiplexor

Other Hardware Motors, Mechanics, Power and CNC
1

I'm trying to control six small steppers, the type out of a cd drive.

I need the controls to take up as little space as possible, right now i'm thinking I can get away with using 1 driver with a multiplexor but haven't been able to find anything on the subject.

Is there any method to this using least amount of space possible and as little power as possible?

I would only be moving one motor at a time and it doesn't need to be particularly fast

2

This gets asked about every 6 months here. 'No' is the answer - you don't multiplex power because
a power multiplexer is already a power driver - you gain nothing.

You are looking for compact multiple drivers.

Can you explain exactly what kind of steppers you mean (are they micro-minature bipolars
or something else?) Need to know number of wires, current, resistance.

3

The steppers are 4-wire bipolars, 10ohm.

Here is the link for where I bought them:

I suppose the question I should have asked is how small can I make the processing/power delivery to the six motors?

Ideally I'd like to keep the driver/processor within a 40mm^3 volume

4

What current are they? Can't seem to find any good data there...

How's your surface mount soldering? You can get very small transistors and MOSFETs - one
sort I used recently was a dual n-p-channel DMG6602 http://www.mouser.com/ds/2/115/DMG6602SVTQ-536621.pdf

This can be configured as a 1/2 H-bridge in one package and is 3mmx3mm. So 4 of them will drive one
stepper at about 8mmx8mm of PCB area.

If you want to use chopper drive then there are various (surface mount) chips for that.

If the current requirements are low enough MOSFET-driver chips could provide a reasonable approach,
for instance this is a quad driver: http://www.farnell.com/datasheets/32331.pdf that would be enough for one stepper so long as you add freewheel diodes
(the most compact way to do that is with one of these I think: http://uk.farnell.com/texas-instruments/uc3611n/diode-rect-schottky-3a-1-2v-dip/dp/2406737?ost=quad+schotky&selectedCategoryId=&categoryId=700000043508 or http://www.diodes.com/_files/datasheets/ds30195.pdf

5

Surface mount is a breeze,

I'll do some more research on these motors to see if I can find anything else.

Thanks you very much for this info, I'll post back once I start working on it and once I finish

Cheers!