Hi! I'm currently working on a project that requires 12 high-powered and fast servos.
I have selected the ds3218 servos(let me know if there's something better I should use instead), but I'm running into issues selecting a board to power these. I've seen people recommend PCA9685 but those don't seem to supply a max of 6.8Volts and enough amperage for the 12 motors(around 25-30Amps total, 1.8-2.0amps per servos). What should I do?
The PCA9685 PCB traces certainly cannot the total current draw of that many high powered servos.
You can wire the servos in parallel directly to the power supply, or use, for example, four PCA9685 PCBs to control and power the servos in subsets of three servos each.
You can reinforce the current carrying capacity of PCB power traces by soldering tinned solid wire on top of them.
I agree with above, reinforcing traces is the most practical solution.
If soldering is not your thing, you could power every 3 servos directly from power supply.
The DS3218 servo motor requires a start/stall current of at least 1.8 to 2.5 Amperes total. For 12 servos, you should size the power source for 25 to 30 Amperes. It's important to ensure your power supply can deliver this current to avoid performance issues.
The simplest would be to power the motors separate from the PCA9685 simply use the PWM output. Be sure all grounds are connected.
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A PCA9685 doesn't supply power to the servos at all.
The board simply passes power from the screw terminal to the servo power pins on the board, the PCA is only adding servo signals to the servo pins.
As others have said, the circuit board traces and mosfet, if fitted, are not capable of carrying that amount of servo current. @kmin gave you a good solution.
Leo..
Thank you for your replies! Is there any boards that can handle that much power? I want to make the overall wiring pretty simple. Thank you!
Likely not. But the wiring can be pretty simple overall...
12 high power 2Amp stall current servos will include some heavy gauge wiring to the 25+Amp power supply.This must be done right, with some soldering involved.
If not, then you will have weak and/or jittering servos.
Leo..