Hello,
I'd like to know if there is a sort of trick for dealing with the driver DRV8843. I'm trying to use it with two DC Faulhaber Motors, but it never works entirely, just one channel works. I'm not using current limitations and, for test, i'm just putting high or low signals at the ports. The motors don't require the maximum current of the IC. Is there any special connection or signal beyond that ones specified in the datasheet?
Thank you.
Leonardo
Hi Leonardo,
You should be able to drive two DC motors simultaneously with no problems. Here are a few things I would check:
1. Make sure both AIx and BIx pins are LO for 100% current scale. If these two signals are HI, then the H bridge will be disabled.
2. Make sure you are connecting motor A to H Bridge A and motor B to H bridge B. It may look like you can combine outputs but this is not true of DRV8843. It will be true of another DRV88xx device which will come out in about a month, but certainly not DRV8843.
3. Make sure the AINx pins are not the same logic level (i.e. both LO or both HI).
I imagine you are making nRESET and nSLEEP HI as one of the H Bridges work. Is this with our EVM, or your own board? If it is your own board, feel free to send me your schematic (if you can) to jquinones@ti.com and I'll take a look at what else may be going on.
Best regards,
Jose Quinones