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Topic: Homebrew "Arduino" with integrated half-h-bridge, 5s LiPO VRM, etc (Read 1 time) previous topic - next topic


So after taking onboard advice from here more than a few months back now, I've had a couple of false starts, some fire, more smoke, a bit of luck, and a lot of excitement all come together into an Arduino Nano style device.. And it works well.

It's a shade larger than a Nano, but includes:
- Integrated half-h-bridge good for about 20a continuous / 80a motor stalls / 150a or so pulses across 2s - 5s LiPO batteries. PWM on the low side.
- VRM to supply MCU and accessories power off the LiPO with additional stuff to avoid brownouts
- Voltage divider to read the current battery voltage (for low voltage shutdown, as well as battery specific tuning)
- CH340 USB bridge
- Break-out pads for an external USB cord.

I have a set of libraries developed to handle things like the battery monitoring, half-bridge control (incl deadtime), etc. Plus example code of common usage scenarios.

The use case is primarily modified Nerf blasters. I tend to swap a variety of high kv BLDC flywheel motors into them and use a variety of high speed / high torque motors, or solenoids to provide auto cycling so it's a real time saver to have an integrated unit.. But having an integrated package available makes advanced mods more accessible for those who can solder up a switch, but feel intimidated by soldering up a pile of discrete semicondutors.

Here's the first samples of a running unit. A couple of small hardware niggles that will be resolved in my next run.

Comparison to a Nano clone

And a video demo

Thanks again for the help.

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