Problem with the vnhsp30 motor controller IC

Hi!

We’re currently developing a motor controller for a submarine robot. We’re using this IC to drive the motors but what we’re having some problems with our design.

We are following the electrical schema that’s posted here (https://www.pololu.com/picture/view/0J409) but we haven’t been able to make it work:

1 - We output a square signal with a 50Hz frequency but in the output we always measure the same voltage (1V). This is with and without any load to speak of, if we plug in the motor we’re trying to drive it doesn’t work. We checked at the input and the signal show up at pin 8 like it should but the IC doesn’t work.

2 - What should we do with the NC pins? At first we left them floating (not following the schema) but once we connected them the problem didn’t go away. Also, why is pin number 7 left unconnected? Shouldn’t it be connected to something? I understand it’s not connected to the neighbor pins because those are control signals…

Thanks!

Hello.

The NC pins can generally be left disconnected; you should refer to the datasheet for a typical application circuit, or just look at our schematic. If your board isn’t working, there could be all sorts of problems ranging from how you are using it to the board itself. Is there a reason why you aren’t just using our carrier board?

- Ben