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How to provide power to 6V HP Gear Motor



I am currently using a Dual VNH5019 motor driver carrier and TWO HP 6V 34:1 Metal Gearmotors. I am going to use a 3S battery to power my setup, so I will have to step down the voltage to 6V to power the motors.
My problem is that, these motors have a current rating of 6.5A at stall, and I cannot seem to find a linear regulator that can provided the required current for BOTH motors (which is around 12A)

Can I provide the voltage directly from the battery? (which is greater than the rated voltage of the motors)
Are there any methods that I can emply to step down the voltage but still supply the same high current to the motors?


Here are some options, but they’re pretty expensive. It would probably be cheaper to get the right battery.


Linear regulators convert one voltage to a lower voltage by dissipating the excess power as heat, so there is a limit of how much current they can handle without becoming very large. As dano mentioned you could use a switching regulator instead (they are much more efficient), but a regulator that handles 12A would likely be much more expensive than getting a 6V battery pack.

You could also supply your motor power directly from the 3S battery you have, and limit the effective voltage the motors see to around 6V by limiting the duty cycle you send to the VNH5019 driver to around 50%.



Thank you for your replies! :smiley:

I have also noticed another thing. When using a switching regulator, the motor is non responsive at low PWM. So I’m switching to a 2S Lipo Battery.