I’ve currently made an arduino project that powers 4 servos (this will expand to 6 servos and include a display modeule however in the future) that works off of 1x 9V battery (powers AtMega328) and 4x AA batteries (powers the servos). This all works fine, however I wanted to make changes so that I can power the servos off the mains electricity so I don’t have to maintain the AA batteries (as it means I need 4x AA alkaline batteries or 6x AA NiMH batteries to power this many servos with adequate current).
(I’ve attached what I believe my circuit should resemble at the end of getting the circuit changed for using with a wall wart. Please note, I’ve moved the AtMega328 chip from the Uno board to the breadboard as in theory I’ll be doing this at the end of the project).
So I begun looking into how to do this and I figured I could get a wallwart that could provide 5A-6A of current (this is because the servos can draw up to 1A each depending on the load; unlikely to need that much but of course you should try to budget for this eventuality) and 6V.
I also looked into DC-DC switch converters to step down the voltage if need be from the wall wart (link below to one of those I found). Introducing a DC-DC converter seems to add a bottleneck where I can only draw 2A at most without a heatsink, so this raises an issue I’ll probably put in another post.
Unfortunatly, I’ve not had uch luck in finding a wall wart that can supply adequate current, the closest I could find was a laptop charger but that was more money than what I wanted to spend and also seemed a bit overkill.
That’s the background spiel, finally, on to the questions!
Can anyone reccomend a wall wart that would provide at least 3A (the closer to 6A the better), at least 6V and is also not too pricey or bulky?
I havent got any available wall warts around the house, but I have been looking at ones being used and am left slightly confused. Most of my wall warts only have an output of 2A at the very most (the majority are actually 1A or 1.5A) and they power things I would consider quite power intensive. Am I just completely overestimating the max current on the servos or is there a trick I’m missing to boost the current in the circuit without having the power supply provide the current?
I did check the current on the multimeter when each micro servo was under a heavy load (standard servos wil lbe added once they arrive in the mail) and it came to around 800 mA.
If you have multiple power supplies in a circuit you need to connect the grounds, if I do this with a battery and the mains power, will this cause issues (i.e. cause the battery to explode!)?
Thanks as always, I really appreciate any help anyone can provide this newbie