Hey all, I'm having trouble with an L298N. When I connect a 12v power supply, using my Arduino Uno, I can run a stepper and/or dc motor with no problem. But, when I connect a 24v power supply to the L298N to run a 24v dc motor, it arcs and shorts out my power supply. I have removed the jumper on the L298N, I have a common ground with my Arduino Uno and I am supplying 5v to the L298N regulator from the Arduino. I have tried it with three different (of a three pack bought from Amazon) L298Ns, same result. I've searched the web, and looked here for a thread addressing the same type of problem. No luck. Are there variants of the L298N that won't accept >12v? Thanks for your thoughts.
The L298N chip works at over 40V. The L298N module you have is a completely different item. Please post a link to the module.
The L298N is not a stepper motor driver. It is intended for low power brushed D.C. motors.
And, of course, the ancient, extremely inefficient L298N chip has always been highly overrated by sellers, and can dissipate only a fraction of the power they would like you to believe. There are thousands of posts on this forum describing the troubles people have with them.
You would be much better off using a modern, efficient motor driver. Pololu has the best selection.
Thanks for the input. Here is a link to the three pack I bought.
They say 40 volts in the advert but it shows 35 volt caps.
Given that you may want to take some of the other claims with a pinch of salt too.
Did you not see this warning on the product page?
To avoid damage the voltage stabilizing chip, please use an external 5V logic supply when using more than 12V driving voltage
As I suspected, they used a cheap voltage regulator to supply 5V to the logic, and it has been destroyed.
In principle, you need to remove the "5V enable" jumper to prevent that from happening. An abysmally stupid design decision.
I did see that warning on the product page, and I did remove the jumper before I applied 24v. I am supplying the 5v to the logic from the 5v output on the Arduino. The L298N seems to work as advertised with <=12v, but anything above that it acts like it dead shorts the power supply. At any rate, I took your advice and ordered a few of Pololu MAX14870s, a couple singles and a double. I only need a single for this project but thought it would be good to have something on hand. Thanks for the help. 
It sounds like you got defective boards or counterfeit chips. Send them back to Amazon.
You might shorten the title of your post to L298N = trouble, which is generally true.