A4983 stepper carrier (p/n 1201) shorted vdd-gnd?


I recently got four of the 1201 stepper driver carriers for use in a RepRap. Today I got my breadboard set up to test just one carrier, and when I applied power to the setup, my (separate) 5V reg shut down for overcurrent.

I had the Rep Rap mother board connected for step, dir, enable, and I had the stepper connected to the motor outputs. The motor was jittering but not really doing anything else. Turning the 1201’s pot didn’t seem to make a difference.

Tracing the VDD and GND showed I have a 1.5 ohm short between VDD and GND on the carrier board. This exists even when the carrier is entirely disconnected from the circuit. I dropped in one of the other carriers without changing anything on the breadboard and it works fine.

Is this carrier screwed? Could it have come that way, or did I do something to cause it? Have you folks seen this sort of thing before? I looked at it under magnification but I can’t see anything amiss.




Do the other boards work? Do you not see that 1.5 ohm short on the other boards when you make the same measurement?

- Jan


I’ve only powered on one of the remaining 3, but I’ve measured all 3 of them. The one I’ve powered on works fine, and there is no 1.5 ohm short between the VDD and GND pins on any of the 3 boards (they read as open circuit).


You should email us directly (make sure you include your order number) for an RMA number.

- Jan

ok, cool. Any particular address like sales@ or www@? (I couldn’t find a specific rma address on the contact page)



The www address would be fine.

- Jan