L298P on RoMeo BLE v1.0 Overheating

Help & Support Robot Parts
1

I’m building a remote controlled car. There are two problems I am having which I think may be related. Problem 1 the motor doesn’t run. Problem 2 is the L298P IC is overheating.

Part List:
Microcontroller: RoMeo BLE v1.0
Motor: 12T 550 Traxxas, 8.4V DC
Battery: 1S Tutti LiPo
Basic Car Set up:
image5
Batteries are hooked up to the external power and the motor pulls current in parallel from the motor driver.
At 11.1V the motor pulls 3.8A, at 7.4V the motor pulls 3A, and at 3.7V the motor pulls 2.4A
The batteries are hooked up so theres two sets of batteries in parallel and within each set there are two batteries in series. Each battery is a 1 cell LiPo so there is 7.4V entering the system.

Description for Problem 1:
In general the motor has not run when I press the button to run. The microcontroller is receiving a signal because I can turn the LED on the board on and off. The last time the motor turned on was when I was doing some troubleshooting and after pressing the button that should have turned the motor off the motor began running for several seconds then stopped.
Description of Problem 2:
Whenever I try to run the motor whether it’s at low or high voltage the L298P chip overheats. It gets hot fast and burns at a touch. I’ve checked the data sheet and I do not appear to be surpassing the current limit of the chip. I even pull current from two motor drivers for one motor to limit the amount of current pulled from each driver.

2

This is the issue. The L298 is meant for 2A max current, and better at 1A continuous. The motor you are using is too powerful for this chip.

2 Likes
3

This would be a problem if I was supplying all current from the motor from one driver but I’m using two drivers effectively decreasing the current flow from each channel by half. At 3.7 V each channel outputs 1.2A, still under the 2A/channel limit.

4

My apologies for not seing that. It really does seem to be a current issue somewhere.

Motor:
https://traxxas.com/products/parts/motors/titan12T
No specs, so can only assume the ideal

Motor Driver:

Note that DFRobot suggests an input range of 5V to 23V. It might be the inefficiency at 3.7V causing the issue.
Can you try with a higher voltage? It makes sense to use a 2S LiPo.

5

I have tried using a 2S lipo battery. The current is 1.5 per channel but the chip still gets insanely hot. Ive even sent a voltage lower than that of the battery via the program updated to the microcontroller and even with 0.6A leaving each channel the L298 chip still overheats. Ill consider trying a different motor

6

The L298 series is incredibly popular for hobby robotics, and although the chip does get really hot when handling higher current, what you describe and the way you describe it, it might be handling too much current or something is wrong. If you tell us more about the application, perhaps we can suggest another motor. You can also add a heat sink to the driver to help dissipate the heat.