[Yaaarc] Suggestions for hacking an RC car

[Erik Kauppi]

How many amps do the motors draw?

Do you need forward and reverse, or just on and off?

The L298 is a cheap and easy H-bridge for a couple of amps, but you lose 
several volts through it, which is not so good.

The MOSFET circuit used in the Y3MD has very low losses.  With big heat 
sinks it can handle 30 amps or so, probably overkill for your 
application.  But the parts cost is only a few dollars and the engineering 
is already done so it might be a good solution.  If you built it without 
the heat sinks it could be pretty small.

If you don't need reverse you could use one MOSFET,  I like the IRLZ44N, 
you can drive it straight from a CPU pin.  Put it on the ground side of the 
motor and everything is easy.

We have a few of the MOSFETS laying around here if you want to pick them up 
at Corsa.  I don't think we have any complete Y3MD kits left though.

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At 09:26 PM 8/7/07, Sondra wrote:
>Hi all,
>
>I am hoping to hookup a Butterfly to an RC for the Sumo Contest.  The back 
>wheels have their own motor and I can do something very simple and ugly 
>like control relays or perhaps a small H-bridge.  Can anyone recommend a 
>small H-bridge, possibly to fit on a breadboard?
>
>For the front wheels' motor, would these take PWM?  I suppose I can try 
>that out as soon as we get our Butterfly dev environment setup.  I did 
>manage to get a "Hello World" message on a Butterfly, truly exciting, but 
>still need to get gcc setup for it.
>
>Thanks!
>-Chris O and 3 kids
>_______________________________________________
>Yaaarc mailing list
>Yaaarc at stilyagi.org
>http://stilyagi.org/mailman/listinfo/yaaarc

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There are 10 kinds of people: those who can count in binary, and those who 
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-- Erik Kauppi -- ekauppi (a) corsa-inst.com ------