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Hey I built a tanks and it runs on dc motors. I am powering these motors through my arduino but my arduino doesn't give off enough amps. How do I increase the amps?

Oh and i'm looking for the easiest way so please no expensive motor drivers.

Thanks smiley
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Use high current logic level N-channel mosfet transistors to switch motors on and off or variable speed with PWM commands. Arduino can drive the transistors but doesn't have to supply the high current the motors require. If however you require bidirectional motor control, forward and backwards, then there is a need to have H-drive motor controller.

It's hard to give specific device recommendations without knowing the motor voltage and maximum current requirements and how many motors are involved.

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Oh and i'm looking for the easiest way so please no expensive motor drivers.

Guess that just leaves the inexpensive motor drivers....
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Guess that just leaves the inexpensive motor drivers....

The cost of H-drive motor controllers is proportional to the power of the motor to be controlled. Without your motor's voltage and maximum current requirements known, it's hard for anyone to recommend anything.


Lefty

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ok well the motor is the standard toy dc motor but i don't know the specifics heres a pic


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ok well the motor is the standard toy dc motor but i don't know the specifics heres a pic

You could probably get away with an L293 (~ 600 mA) or L298 (~ 2 Amp) h-bridge IC based controller. These ICs can drive up to two DC motors; the L293 can source up to 600 mA per motor, and can't be bridged (that is, you can only run two motors off one chip - you can use a single chip to drive a single motor such that you get double the current rating. However, I have heard of people "stacking" L293's to double the current, if needed.

The L298 can source up to 2 Amps per motor (depending on the variant - check the datasheet; IIRC, the L298N does 2 Amps) - or you can bridge the two outputs (thus only driving one motor) for up to 4 Amps, if needed. Note that it is best to get the L298 as a pre-built controller, it doesn't have a standard 0.1" pinout and -will not- fit on a breadboard (there are adaptors for it, though - see http://www.jrhackett.net/L298adapter.shtml).

To figure out what you need - first look on the motor (the plastic end-bell where the terminals are, mainly) - there may be a manufacturer name and model number there; these motors look like cheap Mabuchi hobby motors though, likely rated 3-6 volts DC at an outside max of 1 Amp stall current.

Put your multimeter in current measurement mode, and place the leads inline on the motor (DO NOT DO THIS IN VOLTAGE MODE!), then apply 3-6 volts and note the current consumption - that's your running current. Do the same, but grab the shaft to stall it - that's the "stall current" - or the maximum current you need to be able to supply. If it it greater than 600 mA, use an L298, otherwise use a L293.

Note, also, that you may need a heatsink on the motor driver IC if you are going to run the chips at anywhere near their maximum output - so keep that in mind as you test and shop.
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