12V DC to Variable DC, Off-the-shelf solutions?

[tx2sturgis]

A lot of electronic devices that operate on DC, and some devices that operate from wall-warts or power bricks automatically adjust to the input voltage. It's quite common for laptop bricks to even state on the label something like "Input Voltage 110-240 VAC". 

Many solar controllers test the voltage of the battery bank when first hooked up to determine if its a 12v or 24v bank. 

Lots of modern high brightness LED emitters have small built-in regulators that regulate the voltage on the chip to exactly what it needs, no matter if the input is 5 volts or up to maybe 15-20 volts. 

Of course the assumption here is that the devices you want to power, want what they want...and nothing else will do.

If you accidentally feed 20 volts directly into the bottom of that expensive iPhone, it probably won't like it very much!

 

[B and C]

Your list is similar so far to the DC devices I'd want to power, though mine includes some other things to charge like hair clippers (4.5V/1A), a VHF radio (6V/0.5A), maybe a wireless router (9V/0.6A), and perhaps a few more.

What do you still run off the inverter?

My small (550 watts MSW inverter) supplies a power strip that my FRS radio charger base, hair trimmer, satellite receiver, etc. are plugged into.  These are all small loads and I could have gone with a smaller inverter, but doesn't seem to be a problem as I have 250Ah of battery and 400 watts of solar and a generator to back it all up if needed.  My suggestion is buy the biggest solar system/battery setup you can afford and don't sweat it.  Just try to run as much of the stuff as you can with least amount of step up/down of voltages.  The double conversion process is wasteful.  Here is the desktop I carry, https://www.amazon.com/HP-EliteDesk-800-G2-Desktop/dp/B01MR5NFHW .  It runs off the laptop 12VDC adapter that converts to 19.5 VDC.  

"...maybe a wireless router (9V/0.6A)...".  My hotspots have routers built into them with a maximum of 5 devices (ip addresses) connected, but this is all wifi connections.  If you need the faster ethernet ports for moving large amounts of data, a seperate router is feasible.  You are talking very small power loads.

No need to reinvent the wheel when the technology is mature on what works now.  I do believe that in the future, there may end up being the technology to plug in devices that would communicate to the source what they require for power.  Not there yet.  Invent it and become rich beyond your wildest dreams.

Good luck.

 

[MrAlvinDude]

The output has only two, 

Actually some of those DC plugs has three connections. 

The outside of the big round ring, the inside of the big round ring, and a center pin. 


So on those units the PC and the power supply actually talk to each other. I don't know the protocol or what they talk about, but I do know that it usually is more advanced than the Apple style where it is just measuring a resistor.