On Sun, 4 Aug 2002, Sean H. Breheny wrote:

>Hi Morgan,
>
>Thanks for the quick reply. As for bipolarity, I think that this is
>completely equivalent to a bipolar drive (just like feeding a brushed motor
>with an H bridge and flipping the polarity around). Of course you are
>right, it is probably more efficient if you include more points of the sine
>wave (you wouldn't really want off, you would want 0 volts, which is
>different), but I don't think that a square wave would cause 7 or 40 times
>more current.

Unless the original driver uses a chopper and/or a buck regulator to feed
power to the windings, which is highly likely because that's the state of
the art.

Peter

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