I have a Nema 17 stepper motor which I want to control using a TMC2209. I managed to get it working but now its stop working and I don't know why. I have replaced the TMC2209, stepper motor, wiring, power supply and Arduino board. The only thing I can think of is that I have the AMPS set incorrectly. I set the AMPS based on an instructional video I saw online - stating stepper motor rated amps (1.5) x 0.71 / 2 =2.13 volts, which I done connecting my multi meter to GND & VREF on the TMC2209 and turning the dial to get the voltage of 2.13. This is so annoying why it is not working anymore, I'm sure it is related to the amp setting but I am not an electronic expert and I'm struggling troubleshooting this.
These are my components;
TMC2209 stepper driver
Nema 17 stepper motor rated at 1.5A-3.8V
24v 5amp power supply
Power converter buck steps down 24v to 3.8v
What is the usage of this buck converter? Please show a schematic how everything is connected.
You must not connect a buck converter between the PSU and the TMC2209. The TMC is your 'buck-converter' to control the current through the coils. The 3.8V of your stepper is irrelevant, only the rated current is important. The TMC must be supplied with much higher voltage than the rated voltage of the stepper.
I am using a LM2596S DC-DC Buck Converter because I assumed it would pass 24v straight from the power supply to the stepper driver and motor unless I did. I was worried about things getting fried. I confess that I an not an electronic expert, it just seemed like the logical thing to so that I don't have 24v going straight to the stepper driver and motor. As you mentioned " The TMC is your 'buck-converter' ", this did not cross my mind.
The only thing I changed from my drawing in the last attempt to get it working was to add another Buck Converter which is set to 5v and I connected it to the TMC2209 logic, just in case the Arduino board was being overloaded, I also connected the 5v Buck Converter GND to Arduino GND. However, the schematic drawing is my original setup before I got desperate trying different things.
Thank you MicroBahner. Removing the buck converter was the solution (which Stefan also suggested). I can stop hitting my head against a brick wall now!
