Looking for AVR brushed motor controller kit

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Hi guys

As the headline says, I'm looking for an AVR brushed motor controller kit.
I'd like to make the board myself, but I'm both too strapped of time and a little too poor at the moment to go through the whole prototyping phase.

The kit needs to be programmable (of course), able to drive a regular brushed motor, have the possibility of active breaking and be able to deal with peak currents (0.5 - 1 sec) of up to 40-50A. Continuous current of ~20A.
Supply is from a 2S, 3S or 4S LiPo (4S only of the others aren't possible).
Also, it should be compact-ish.

Do any of you know of such kits?
I've checked various sites like Sparkfun and Atmel's own shop, but only found boards based either on those nasty PICs or full H-bridge controllers.

Any help will be greatly appreciated.
Cheers :)

EDIT: The motor needs only to run in one direction, so H-bridge isn't necessary.

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Most of my projects are capable of active breaking. Usually involves large current flowing through places it wasnt designed to flow through, resulting in emmision of smoke. I think you want active braking, but it is also called dynamic braking (shorting motor to ground) or regenerative breaking (letting motor charge a cap through a pwm controller for a variable load). I'd get a big IGBT or a big mosfet and use it to switch the motor to ground. This gives the speed control and is simple. I'll let a smarter dude than me suggest how to do the braking.

Imagecraft compiler user

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I do not know of anything that would precisely match your requirements. If you want to do active braking you will need, at least, a half-bridge ( to switch the motor back to ground. If you wanted regenerative capability you'd need a full H-bridge anyway. I'm not sure there's much to be gained by staying with a single direction system.

If it were me, if designing the board isn't viable, I would just use one of the available H-bridge controllers and take the cost/complexity hit. Of course, if the quantity required is large, it may make more sense to keep searching or to find a way that designing a board becomes possible.

Martin Jay McKee

As with most things in engineering, the answer is an unabashed, "It depends."

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If you haven't already checked out some electric car/bike forums and websites, you might find some ideas there.

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Thank you for your answers.
The requirements are flexible. The half bridge was what I was looking for, so I can short the motor to ground, I just didn't word it very well.
I was thinking something like this:
http://www.electrozone.dk/roboti...
Only with a FET for shorting the motor to ground (half bridge?) and AVR rather than PIC.

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BTW - you probably don't want to actually short the motor for braking. That's the same as short-circuiting a dynamo while it's running, and that usually leads to some unpleasantness.

You might want to dissipate the kinetic energy in a suitably sized resistor bank rather than in the armature windings.

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Just a quick update for anyone searching for the same type of solution:

I ended up buying a 30A Turnigy brushed motor ESC from Hobbyking at 7.12 USD.
I'll interface to that instead :)