I just started experimenting with a micro-controller connected via a Texas DRV8833 Dual H Bridge Motor driver chip to a stepper motor. All was going well, I was measuring the output voltage from the H Bridges, until I connected up my actual stepper motor. I'm only using a 600mA Power supply, which I had lying about. As soon as I connected up the motor it's killing the voltage to the micro-controller.
So obviously my power supply ain't got the juice needed, but then I got to thinking I only want this to turn the needle on a gauge I'm making. So it's not like I need torque so I could limit the current to the stepper motor. I had a look around and found an article [1] which while through maybe raises as many questions as it answers for me. The problem is that the article talks about wasted heat which seems to be the way to limit current. Whilst that obviously works it seems like a bit of a waste to be burning off energy for a needle in a gauge.
It's not mentioned, as far as I can see in the DRV8833 datasheet, or [1] but can a resistor be put between the H Bridge output and the motor winding? Sounds simple so it's probably wrong but even if it is a stupid question I might learn something.
[1]
http://homepage.cs.uiowa.edu/~jones/step/current.html
Thanks a million for that I totally missed it.
