Hello Esteemed Folks! I'll try to be direct and clear with my question, I'm open to feedback for future posts. I'm new to this whole Arduino thing, but I am really enjoying it!
For a personal project, I'd like to create a little walking robot using 8 MG996R servo motors. The MG996R reportedly peaks at a 2.5A current draw, with an operating voltage of 4.8-6V. Running 8 together, I'm looking at 20A peak current draw, which is more than most driver boards want to supply. So I want to make my own PCB (or proto-board) that connects the 8 servos to a regulated current source at 5V with a max of 40A.
I found a DC DC Converter on Digi-Key, used mostly for IT applications, but it runs on the voltage and current I'm looking for. The min and max input voltage are 6 and 15V, respectively. The output voltage can be set to 0.6-5V, I'll be using 5V. The max output current is 40A. Here's a link to the part on Digi-Key.
Below is a crude schematic of my circuit setup (I used TinkerCAD, if there's a better schematic drawer you like, let me know), with some notes. I also plan to power the Arduino or ESP32 on a separate circuit, just to avoid issues with power surges (let me know if this necessary or avoidable).
The idea is feasible and the DC-DC converter looks like a reasonable choice, but an off the shelf or an amateur-designed PCB carrying up to 40 Amperes is out of the question.
Best to split the design into several sections connected by suitably heavy power leads, after consulting a professional engineer with demonstrated skills in high-current PCB design.
Alternatively, each servo could be individually connected to a 3A step down regulator, like these. Then you can use just about any reasonable voltage to power the setup (the higher the source voltage, the lower the source current required).
That's the kind of thing I would have never thought of. Thank you. I think running multiple lines/batteries for servo power will be a better (safer) move. Just as a follow up, do you know of any good boards for powering multiple systems? I've seen different relay and mosfet boards and wondered if those would be a good option.
Another great consideration. The converter uses PMBus for communication (which I'll admit I'm not familiar with), but I couldn't find any information about programming the device.
I've looked at step down buck converters, like this one, would that be a better option?
As an update for any folks reading this with the same needs, I found a good solution. GoBilda makes an 8 channel servo power supply with up to 30A capacity, and I'll be running that with 2 of their 6V nimh batteries in parallel.
