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I'm currently attempting to convert my son's broken 1:14 scale R/C Bugatti Veyron (similar to this) into an app-controlled car using an Onion Omega with a servo/PWM expansion. However, I am having difficulties powering the main drive motor effectively.

Specifically, I have tried 2 different H-bridges connected to the servo expansion - first was an L293D, then an L298N. In both cases, I just can't get anywhere near the torque that I get just by connecting the battery (5 x rechargeable AA cells as per the original vehicle) directly to the motor, and consequently, I can't get the thing moving.

I followed the wiring as described here, with the addition that I have also connected the external battery to the 12V and GND pins of the L298N. With the wheels lifted off the desk and the appropriate PWM inputs at 100% duty cycle (using 50Hz), they spin, but once I put it down, it has about as much push as a fly's fart.

Should I be looking at a MOSFET instead, or should I be able to get this working with the H-bridges I have? I'm a software engineer and have pretty limited electrical engineering knowledge at present.

John Rix
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    The L293 and L298 and all Darlington bridges are notoriously lossy as has been covered in many questions you will see linked to the right. You need an RC ESC made of FETs. And you don't want that Onion absurdity or "app control" which is laggy marketing-department-cost-cutting-nonsense, you want cheap responsive real time MCUs (likely ARM or ATmega, but may others would work) with something like nRF24 radios and proper physical controls with tactile feedback so you can keep you eyes on the model and not on the phone screen – Chris Stratton Mar 25 '19 at 01:10
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    [How crappy are L298 and L293](https://electronics.stackexchange.com/questions/108686/l293-l298-and-sn754410-h-bridge-drivers-on-low-voltage-power-supply) – Andy aka Mar 25 '19 at 11:53
  • Appreciate the comments guys. Am exploring all sorts of interesting tutorials now and learning a lot! Incidentally, I wasn't following any marketing nonsense per se... my son wanted to resurrect his car (and add a camera to it) and I had an Onion that I bought on the original kickstarter campaign and never found a use for. :-) If it's the wrong tool for the job, that's fine though! – John Rix Mar 26 '19 at 23:33

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