DRV8424E: Parallel DC Motor Operation

Nicholas,

For parallel operation, please consider the DRV8256E/P.

https://www.ti.com/product/DRV8256

Regards,

Ryan

I see that there are higher current options available with approximately the same footprint, but I'm working with an existing PCB that I may not have time to order additional parts. Is the original part able to be paralleled?

Also, is the part you are suggesting able to parallel its outputs as well? The datasheet doesn't seem to make any mention of it.

Nicholas,

No, we can't recommend this.  Due to timing variations between the two channels, a direct shoot thru from power to GND can occur when outputs switch.

For DRV82xx parts, part is designed to drive a single H-bridge.  These outputs can't be paralleled either.

Regards,

Ryan

OK that makes more sense. However, we would be using it in a single-directional pump motor (can't run backwards, so no reason to ever toggle the PH pin).

Would it be possible, then, to parallel them if we did not switch the H-bridge polarity? Or, more specifically, is the direct shoot-through the only reason as to why the H-bridges cannot be paralleled?

I realize this is NOT recommended by TI at all, but I'm trying to narrow down exactly why.

Thanks for breaking it down a bit further, what I'm referring to is keeping PH = 0 and only toggling the EN from 0->1->0 so that the output only transitions from Hi-Z to L. So for example,

• AOUT1 and BOUT1 tied together
• AOUT2 and BOUT2 tied together
• APH and BPH = 0, always
• AEN and BEN can toggle either independently or together

Then,

• AOUT1 is then either Hi-Z or L
• BOUT1 is then either Hi-Z or L
• AOUT2 is then either Hi-Z or H
• BOUT2 is then either Hi-Z or H

In any state for this setup, there should be no possibility of shoot-through. Does that make sense?

OK great. That simplifies things quite a bit on our end.