Hi,
I've been using the DRV8312 for the past few months to drive motors with the standard PWM scheme with no problems...
However, I recently changed the control scheme to complementary PWM in order to use the CBC current limiting. This also works fine but I've noticed that the motors get hot when they are not moving.. It amounts to about 80mA of current being drawn when they are being driven with a 50% duty cycle.
There was no extra current or heat generated when using the standard PWM control scheme so it's definitely something to do with the complementary scheme - Is this to be expected with this method or am I doing something wrong?
I've attached a screenshot of the scope trace - this motor is a brushed dc motor so I'm only using 2 phases but we experience the same behaviour with 3phase bldc motors as well.
Any help would be greatly appreciated!
Thanks & Regards,
Rob Maguire