Other Parts Discussed in Thread: DRV8300
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We are having some trouble using the DRV8300DRGE to drive a BLDC motor (schematic shown below). We are using a 12V GVDD supply with a battery voltage of ~40V. I'm not sure if we are misinterpreting the datasheet but it seems like our high side gate outputs never actually turn off even when their inputs are grounded. The datasheet shows a high-side gate low level voltage of 0-0.35V but we are seeing about 10.5-11V when the high-side input is grounded or left open (grounded through internal 200k pulldown). It seems like this 10.5-11V is keeping the high side in a partially on state where current leaks through when the low side is active. On one of the samples tested, turning on the low side of phase A does bring the phase A high-side gate drive down to 0V, however, phases B and C don't do the same and grounding the high side inputs seems to have no effect on any phase with the gate drive voltage staying around 10.5-11V. Could you please inform us if we are interpreting something wrong or if there is an error in the schematic?
