in line 12v>220/40v inverter

my .02cents worth of experience...

NOT that easy.
I mean easy enough to connect terminals 1 and 4 on a data USB socket to any ebay 12-35V ->5V chip/board.
However, your devices will only see it as a slow .1A or .5A charger. Samsungs are happy and do charge (slowly) high end Sonys will just charge at a silly rate and probably become fully charged in a couple of days. Iphones don't bother. So YMMV...

Didn't realise you have to do something more than that, hence bought a second and a third batch of droppers each batch with higher Amps and the last batch with trimmable/variable output so I could keep it slightly higher and test (at say 5.2V). Same result!

Noelex I think in an earlier thread (again by WL?) pointed out to a solution which probably means more boards and extra H/W.
Didn't have time to investigate further, although I just googled and found a decent article which means it will take me an hour to test one of these wirings and report back. Basically a few voltage dividers to get the Data pins some current and negotiate with the device 2.1A charging.
https://electronics.stackexchange.c...more-power-supply-for-my-consumer-usb-devices

diagram here:
NQSOa.png


I've also have an inverter permanently on when on board, feeding 10A two pin sockets on the Vimars (1U) so ppl use them with a proper charger, however I'd much prefer to skip that and use the USBs for that.
If I get some time in the afternoon I'll give it a shot!

cheers

V.
 
Simply fit a cable with USB plug behind the btinco then plug that into your 12v charger of choice behind the scenes. Then you can swap the charger in future, etc.

I would get a decent charger that supports quickcharge, 2A etc. Not any ebay 5v supply.
Anker is a premium "Apple-like" brand in this area - happy customer with only about 20 of their chargers. ��
 
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well, I'm very impressed!

Went out shopping for other things and picked up some 5.1KΩ, 4.3ΚΩ & 7.5ΚΩ in odd combos of values as I didn't have my voltage divider spreadsheet with me and couldn't be arsed to find one online... Tried it out and it does work.

So my -0.1 or so Amp charging on my XPerformance smartphone (with the screen on and backlight on) went up to 1.1Amp (again screen and backlight on) using the "chipped" version :D
Daughter's Samsung is happy (but was with the previous setup as well...)
Wife's Icrap 6S also charges, wouldn't even register a charger on the previous setup!
So seems that a simple data USB a small dropper and 4 resistors are enough to get 2A out of a USB plug.


Going for easier and simpler values I'll get myself enough to built the dozen or so USB ports onboard MiToS!

R1 = 2.7KΩ
R2 = 3.3KΩ

R3 = 2.7KΩ
R4 = 1.8KΩ

Or ιf you want to have the same value on the (-) R3 = 5.1ΚΩ (but not very accurate..) and R4 3.3KΩ

cheers

V.
 
doh!

went through the doc I linked to two posts above, noticed there's this USB-IF BC 1.2 standard which works if you short the two Data cables together with a piece of wire.
Did that and amazingly all devices work and charge exactly as with the mess of all these resistors in place. Even wifes iphone and pad charge just fine.

So guess which one I'll use :D

cheers

V.
 
I remember, back in the day, putting an invertor into a Disco3 so the third-row passengers could run their laptops. I feel you are moving towards a better solution :encouragement:
 
benjenbav said:
I remember, back in the day, putting an invertor into a Disco3 so the third-row passengers could run their laptops. I feel you are moving towards a better solution :encouragement:
Click to expand...

true but a solution with all sorts of odd hurdles!

WARNING:

before dismissing a chip/charger/combo as bad or not performing well, CHECK THE BLOODY CABLE!!!!

Ripped 3 wall plugs and 4 USB sockets from MiToS this morning as I went to wire the 2-3 pins in order to get 1A+ charging and realised than NONE was working, and they were charging/discharging rather with -200mA with the mobile screen on.

Brought them home, ready for some testing only to realise that using another cable they were all fine!

So now testing in my desk I have 6 Vimar IDEA USB plugs, and 4 cables two that I had at home and two I brought back from the boat.
On the XProfessional with Charger Tester, I get 1.2A on the one cable, 0.9A on the other, 0.3A on the one from the boat and -0.2A on the crappy one...

Wonder how I can get decent USB cables for charging androids!
So later on I'm going to refit them all back onboard, nice...

cheers

V.
 
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