In a setup with Leonardo + A4988, I am planning on powering the VMOT of the A49988 out of the VIN pin of the Leonardo. I have read somewhere that VIN can be a pin where you supply the main voltage or draw the main voltage.
Is this wrong?
I want to use a single power source that powers the VMOT and the Leonardo, so by powering Leonardo through its built-in barrel jack and then getting power out of VIN to the VMOT I am accomplishing that.
Attached is my current wiring diagram.
Thanks in advance.
You are correct. The VIN pin on the Arduino Leonardo can be used to supply voltage. You can find more information about that on the Arduino Leonardo page.
I understand a 100 uF capacitor is needed at the entry of power at VMOT and GND ports of the A4988.
I am planning to power the VMOT as well as the VDD out of the Arduino Leonardo (VIN and 5v). In this scenario would I still need a capacitor at VMOT?
Does this mean that the 5v pin can also be used as input and output as well?
It sounds like you are still asking questions about the same setup, so I merged your other post with this longer thread.
I recommend still placing a capacitor across VMOT and GND for the A4988. Also, you might want to consider adding another decoupling capacitor close to the Leonardo for extra protection. In general, having extra capacitors like that in your system should not hurt anything.
Your question is not clear to me, but it sounds like you are trying to use the 5V pin of the Leonardo to power VDD on the A4988. That should be fine.