Re: Reversing motor polarity ?

grubertm@xxxxxxxxx wrote:
I just finished assembling a tracked base on which I hope to eventually
mount my MCU. Each motor requires 3V and if my multimeter did not fool
me draws 300mA max. Direction of rotation depends on the polarity and
the bare bones base has a simple manual switch for flipping polarity.
Now what's the best way to control motor operation and direction
electronically from a 3V, max. 20mA output ? Use a relay (coil or solid
state) ? Mosfets? If this was unidirectional I would probably add a
mosfet as switch, but I don't know how it would deal with reverse
polarity...

You do it with 4 mosfets in an H-Bridge configuration.

This guy has a lot of good basic information on his web site about how it
works as well as a speed controller you can build:

http://www.mcmanis.com/chuck/Robotics/tutorial/h-bridge/index.html

--
Curt Welch http://CurtWelch.Com/
curt@xxxxxxxx http://NewsReader.Com/
.

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