DRV8835 and 3S LiPo power supply

Hi!

I’m using the DRV8835 board by Pololu to control 2x DC motors. Currently, the power for motors is supplied by a 2S LiPo battery so the maximum voltage is within the operating range. The VCC pin is connected to a separate power line, which is stabilized at 5V, so, luckily, I’m not facing any issues with DRV8835’s extreme sensivity to motors’ electical noise.

Now I’m exploring the option to increase the motors’ torque by upgrading the 2S battery to 3S.
This means that the voltage is going to be around 11.1V, and the 3S battery can be charged even up to 12.6V.

11.1V seem to be very close to the recommended 11V maximum and this is even below the absolute maximum of 12V (which is also specified in TI’s datasheet for DRV8835)

I know that following the datasheet limitations is definetely a good practice… But has anyone tested the DRV8835 with a 3S battery ? What are the real ranges for this chip ?

Good engineering practice is to never challenge the manufacturer’s “absolute maximum” ratings.

Your robot will probably work for a while if you decide to ignore that advice, but a much wiser path would be to choose the appropriate motors and driver for the project.

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