SimbaDogg

Anyone know if there is any way to increase the amperage that is capable of being output of the 12v DC socket in car? I bought a dual USB plug that is capable of outputting 5v at 1.3 or 1.5 amps for charging electronics (phones, gps, tablets etc), but I using a utility on my phone I've noticed that it only outputs something like .3 amps so phones charge very very slowly. Is there anyway to hardware a line so it can suck down more current when needed?

BlakeNFR

You might have better luck asking the electronics section.

loaferz

Correct me if I'm wrong, but I believe the accessory slot is already rated up to 10A, and a 5v usb charger running at 1.3/1.5a is going to be pulling a lot less current than that at 12v. I suspect it's something wrong with the charger (have you tried plugging it in to any other cigarette lighter and get the same results?), can also test this by hooking up 12v directly to it if you have some sort of variable PSU. Also check that the cable you're using to charge it is capable of delivering that much current (plug it into another usb outlet and see what you get), too thin of a wire or too long will limit the current it can carry, also there's the requirement that the two data pins D+ and D- be shorted on the usb so that the phone recognizes it as a high current charging cable/device.

SimbaDogg

I've looked into different cables, as well as different chargers, and I always run into the same limitation. For example, lots of smartphones now, when the battery completely dies, it needs to charge for a few minutes before it'll actually allow you to turn the device on. On a regular 1 amp charger, after being completely dead, it should take maybe about 3-4 minutes for this to happen. In my car the other day, after about 40 minutes of charging it still wouldn't turn on.

So yeah, all the microUSB cables that I have in my possession work just fine w/ 1 amp chargers, HTC, Nokia, Apple and many other OEMs (aside from samsung) support 1 amp+ for faster charging, but in every case cables that worked just fine in my house (1 amp, or 0.920 to 0.960 amps) would slow charge while in the car.

loaferz

then I suspect it's the dual USB plug that is faulty. I'm about to do this to my own car except that I'm going to hard-wire the adapter to the 12v line on my radio. That line is rated for 15A and the max that the radio can pull is 10 so I should be okay, I'll let you know if I run into the same problem.

SimbaDogg

I thought the same, but I've run into the problem w/ chargers that were rated at 800 milliamps, 1 amp, and 1.5 amp....all of those chargers only output a fraction of the percentage that they were quoted at when used in my car. And I know for sure it's not the testing device, because in my house it works to within 4-8 percent or so of that the charger is actually rate at. But keep me posted if you can, i'd appreciate it

skylinrcr01

I have had no problem with my high output charger (http://www.amazon.com/Original-Sony-...on+car+charger). It outputs the same as my wall charger (2 amps). So I'd guess it's the charger you are using.

loaferz

yep, I just got this in the mail today (http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1), getting high output (750mA) when charging my phone, im guessing it's your charger.

SimbaDogg

loaferz, you can verify that when charging you're getting 750mA to the device?

loaferz

I will admit I might have spoken too soon, when I looked at the battery menu on the phone I saw "AC Charging" which I assume to be high output as anything else (USB) should be only 500mA or less, however I downloaded battery monitor widget and noticed I was only getting at a max +356 mA. Whereas when plugged into the wall I was seeing closer to 750. When I plugged the USB cord into the usb slot on my head unit it detected it as "USB Charging" which I would expect, but battery monitor widget was only showing a measly +3 mA for charging. :/ I'm going to test this more extensively next week, I bought an alligator to cigarette lighter socket adapter so I'll hook the car charger directly to a 12v PSU and see how much current it can draw. I'm also a little weary of that battery monitor app as it won't update the charge rate until after a few minutes, what were you using to measure current in?