Re: Bipolar H bridge switch
Posted by
Jon Elson
on 1999-07-11 21:56:18 UTC
TADGUNINC@... wrote:
leg a transistor, then you have 4 transistors. The horizontal bar
is the motor winding. The 2 transistors at the top are connected
to the power supply, the 2 at the bottom are connected to ground.
Now, you can turn on diagonally opposite transistors only, or it
will short out the power supply to ground. When you have the
upper left and lower right on, current flows left to right through
the winding. When you have the upper right and lower left on,
current flows right to left. This allows a single power supply
voltage to be applied with either polarity to a single motor winding.
It is also called a full-bridge switch. It is used to drive bipolar
windings on stepper motors, and gets the most performance
from most steppers, as opposed to unipolar drive systems.
It also uses twice as many transistors as unipolar, but that is
the tradeoff.
Jon
> From: TADGUNINC@...If you draw an H, and make the top and bottom of each vertical
>
> What is a bipolar H bridge, in relation to stepper motors?
leg a transistor, then you have 4 transistors. The horizontal bar
is the motor winding. The 2 transistors at the top are connected
to the power supply, the 2 at the bottom are connected to ground.
Now, you can turn on diagonally opposite transistors only, or it
will short out the power supply to ground. When you have the
upper left and lower right on, current flows left to right through
the winding. When you have the upper right and lower left on,
current flows right to left. This allows a single power supply
voltage to be applied with either polarity to a single motor winding.
It is also called a full-bridge switch. It is used to drive bipolar
windings on stepper motors, and gets the most performance
from most steppers, as opposed to unipolar drive systems.
It also uses twice as many transistors as unipolar, but that is
the tradeoff.
Jon