How to use 2 H-Bridges L298N in one Dc Motor, as if they were one

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LeoDysarsz

Joined Jul 27, 2018
1
Hi everyone! I’m new to eletronics and I’ve got this project with a big robot that uses strong motors, though the thing is, I’ve got to control them using Arduino and H-Bridges L298N which work (well, they almost do). My main issue is that if I use only one H-Bridge for each motor it gets super hot, so I wonder if it’s possible to divide that heat to a second H-Bridge using both as if they were one, just like when you use L298N to control a Stepper Motor but using a second H-Bridge instead. I posted some pictures to explain my ideas even better. The first picture is the H-Bridge I’m using, the second picture is how you control a stepped motor with it, I want to know if it is possible to intead of connecting the four wires of the stepper motor in one H-Bridge , can I connect two in one and the rest in another? And how should I program it afterwards?
 
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danadak

Joined Mar 10, 2018
4,057
Sounds like your H Bridge is having its ratings exceeded or its not properly
heatsunk.

The application note says you can parallel to 3.5A. Eg. you are not going to
double the current capability, because power transistors are not matched,
have (probably) pretty sloppy ratings of sat beta and sat R effective. Page 2.

https://www.st.com/content/ccc/reso...df/jcr:content/translations/en.CD00003776.pdf

You could use 1/2 of one, say lowside, 1/2 of the other, highside, and that would
cut the power down in the respective package/dies. But thats tricky because of
timing consideration if you are NOT using deadband PWMs.

Either get a more capable part, do a discrete design, or better heatsinking. In
any case make sure you are not exceeding any ratings.

Regards, Dana.
 
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