> Can anyone help me figure out a DC motor that I took from an old CDrom 
> drive?  It seems to be a brushless DC motor and was the one used to
spin 
> the CD.  It is mounted on a small PC board attached to a narrow ribbon 
> cable.
> 
> The question is that this ribbon cable that attaches to the PC board
has 
> 11 leads.  My question is what are all those leads for?  I've googled 
> for answers but haven't found any.  Stepper motors, yes.  But this one 
> not yet.

The usual answer with these is that those extra leads are for the hall
effect sensors.  Most of these low-cost brushless motors are not
commutated at the motor; there is a controller chip somewhere else that
does the job. To get the information about the rotationnal position of
the windings, you can either use Hall sensors or do some back-emf
detection. Hall is usually cheaper. 

So the cable would break down like this:
3 coils @ 2 ea = 6 wires
3 Halls @ 1 ea = 3 wires
Hall + & - = 2 wires

Note that often the Halls run on less than 5V, derived from the 5V rail
via a (very important) current-limiting resistor.

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