For every board failure I’ve seen here on the forum, Carbide’s been on top of it with a replacement.
Did look a little at it but I know they’ve done a newer board since the v4.3 I have. I have heard that it has more IC’s on it, but I haven’t seen one myself. I’m guessing it has a separate driver per phase on the new one. I didn’t think it was worth messing with until I had a real problem. I’ve stalled the spindle a few times, which has put the driver into overload (I think…it’s either that or the phase detectors are out of whack with the software), but you can recover from it by removing all the power from the board and restarting things. When I looked at the spindle driver vs. the new motor, it’s well within spec. I would take a better part without much argument, but there isn’t anything pin compatible, so it would take building a new board…that I just really wasn’t up to doing.
Another one to look at is the lack of snubber diodes on the servo drivers. That one in particular I don’t quite understand, and sort of bothers me. In the demo board for that driver there are optional snubbers, but they aren’t in the reference schematic in the data sheet at all. In every one of the “open” boards with that chip I can find they don’t include the snubbers. For the 20 cents it would add to the board, would probably make it a lot more robust. I’ve asked around, and can’t seem to find a reasonable answer to why they aren’t there on any of the open boards (I’ve heard a few “because they aren’t on the schematic” answers, and a few “I don’t know, it seems to work fine without them”) The bigger the servo, the bigger problem it would be I think. I hardly do anything electromechanical for my day job, so I’m sure there are plenty of others out there with better area knowledge on this.
If you come up with something, would like to see how it goes.