Asked — Edited

L298n With Separate Power Supply


The L298n video shows DJ attaching the bridge and ez-b to a single power supply and it looks like the ground for both circuits goes through the ez-b.

I need to use a 12V supply to the ez-b and a 7.2V supply to the bridge.

How does this wiring setup differ?



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Don't quote me on this as I haven't seen the schematic for it but I would assume that VCC & Ground which come from the battery would be taken from Supply #2 (Supply #1 being that for supplying the EZ-B). AFAIK that is how they generally work.


Let me put this a different way...

Is it possible to use two separate power sources with an h-bridge?

Specifically, I want my motors to be driven by a 7.2V power source while my ez-b is controlled by a 12V power source.

If I wire them using below diagram, I would be feeding 12V into the h-bridge. The problem is, I'm not sure the little motors in my OWI-535 robot arm can handle 12V but I'm pretty sure 7.2V will be okay.

Does my question even make sense?



So where is the ground connection for the EZ-B?


Connect the GND from the EZ-B Battery to the ground from the L298N Battery:)


I guess I need to brush up on my electronics.

I was afraid current might flow the wrong direction if I did that because there would be potential between the EZ-B ground and the 7.2V battery ground.

I guess I need to break out my multi-tester;)


Please keep one thread per topic.:)

Again, the answer is connect the GND of the two batteries together. That is the answer to your question

Also, the EZ-B does not require 12v. You can simply connect the EZ-B to the same power source as the motor and not need two power sources:)