DRV8833 Not Providing Enough Current

Hello, I have a question about the current being drawn through my motors when hooked up to the DRV8833. If I connect the motor directly to my battery (3.7-4.2 V LiPo), I pull about 1.2 A, which is about what I need. When I connect through the motor driver, I only pull about 0.8 A, which is not giving me quite enough power for my application. For testing the maximum current output I am not using a PWM signal for the motor input channel, I just have A1 hooked up to VIN and A2 to ground.

Is the lack of current simply a limitation of the motors I have chosen or is there something I can do to draw the current I need? The 0.4 amps really makes the difference in my application. I can run the circuit with a 2 cell lipo at around 8v, but then I run into the opposite problem, the motors try to draw too much current and end up barely spinning, which i’m guessing is a result of the drv8833 attempting to protect the circuit from too much current.

Hello.

I am not sure why connecting a 1S LiPo to VIN and AIN1 like that did not work for you. (Brushed DC motors will draw current proportional to the voltage applied across their motor leads, so I do not think it is a limitation of the motor.) However, connecting a 2S LiPo to AIN1 might have damaged that pin, since its absolute maximum rating is 7V.

Can you try connecting the 1S LiPo to BIN1 and BIN2, and switching your motor over to BOUT1 and BOUT2, and see if you observe the same behavior? If so, can you post pictures of your setup that show how you have everything connected?

-Jon