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Accessories I recommend this car charger

Indeed, very confusing. The one I received explicitly had USB12V2A and 1A x 2 printed on the box and included instructions with the same. BUT the top of the box had only reVIVE rather than reVIVE II.
 
OK, I'm starting to believe that the temperature does make a big difference (as would be expected), but not 100% as I have been having some battery issues for the past couple days.

Here's some of details:
Griffin PowerJolt 2, 15' USB extension, 6' micro USB cable, Moto car dock
Time 1hr 10 mins.
52 miles
94 degrees out
Heading west at 6:00 PM (i.e. the sun is beating down on the back of the phone)
Phone temp 94.1 degrees
Battery 30%
GPS enabled and using navigation
Bluetooth enabled, no calls as BT headset started beeping low battery but it stayed on
Streamed radio for 1/2 hour and played mp3 for other 1/2 hour

End of trip:
Phone reads 120.2 degrees
84 degrees outside
Battery went up to 50%, but from 40% to 50% took almost the whole drive

Within 2 1/2 hours my phone was back to 30% without doing anything on the phone. The battery percentage only reads 10's so I don't think it was actually at 50%.

I was going to do the round trip but as I said my battery (really my phone) has been acting up the past couple days so I was not sure how reliable my battery usage is.
 
I received my Scosche today. I think I may have found the source of some of the confusion.

My unit has a model number of USB12V2. The box says Scosche reVIVE and the box and unit itself say Output 5V, 1A.

I did not get any slip of paper in the box.

Scosche site lists a model USB12V2A and says reVIVE II.

Looks like they might have added an A to the end of the model and made it a 2A total unit.

What model numbers do you all have, where did you order from and what's written on the unit itself as far as total output amps?

Bummer, looks like I got the wrong one. The buy.com link I ordered from doesn't have the A at the end, so looks like I'd have little recourse.

Very observant. I am in the same boat (no "A") -- and I can't return it either as I only had 14 days.

But this begs the question, should we have purchased the:

USB12V2A

or the:

USBC3

And, does it maybe make more sense to purchase the USBC3 if the phone, with everything turned-on and running (gps, music, phone), actually requires more power to charge than a 1amp power supply can deliver.

I'm assuming that like other electrical equipment, you can feed the Droid X 2.1amps without being concerned about damaging the phone or the battery -- as it will only consume what it needs at the time.

Is there a consensus regarding the validity of that statement?
 
I'm a little annoyed that the lack of documentation and minor change of model number for a major change in product has caused this confusion.

I did email scosche for confirmation so we'll see what they sassy, but probably not much recourse.

I really need a 2x1A unit this week though. Are there any B&M stores that carry a unit that will give 2 devices 1A EACH when plugged in together?
 
When you charging battery overnight, unless you are using some unreliable after-market charger instead of original OEM, the charging up should be fast even with a number of live-update widgets if you use any. I don't expect you using GPS/NAV or BT to make calls while sleeping :) If battery is being drained I assume charger should pick it up and charge it up. Unless there is some heavy duty use by some unknown app you installed which doing something fishy in the background. I would minimize use of installed apps, cut down on widgets, get free Advanced Task Killer and than see if you still have a problem. If you do, better head back to your wireless store and let them look at the phone and the battery in case there is a hardware issue.
 
I ordered the Sc unit described on this post. Not sure which model I recvd bec as stated...the box did not tell me much. Any way, plugged it in, turned on gps, screen to 100% brightness, did not charge the phone..but did not drain the phone. Held steady at 50% whole time. Are we uncertain that we should have recvd the 1000 per side? I was hoping this unit would not only power phone in gps mode but charge as well.
 
Oh it is charging the phone up but you reached an equilibrium where everything else you have turned on draining the battery at the same rate. And as others, including myself, noticed with extra heat from outside battery efficiency goes down and it drains faster. Based on my observation I found 2.1A dedicated iPad chargers, such as Griffin PowerJolt2, to work better with DX. Scosche has its own dual charger with 2.1A and 1A ports, but it was sold out. Between USB12V2A and PowerJolt2 I have now, Schosche unit is going back to Amazon.
 
Nice find. I have a USB port on my CD player that I plug my phone into sometimes...but when it dies its not even enough to turn the phone back on after 15 minutes.....I think i may purchase one of these.
 
I did fail to mention..as stated before..I to found the phone to be hot while gps turned on and charging with SC unit. The phone read 137 degrees. I am in Fla, it was a mild 96 outside with 180% humidity(not really). Is there a boiling point with the phone? Thinking 137 is high, could have cooked an egg on it. Seems normal temp is approx 80-90 degrees. If I am not getting 1a, don't really know if any higher would literally cook the phone?
 
For what its worth, looks like the item here is the revive 1...tech said only diff btw it and revive 2 is cosmetic...he said the revive 1 when connected to 1 side it is 2a, when 2 devises connected...1a on left, 1a on right...no wonder my battery was reading 137 degrees...serious charging...I agree to what yall have said...the X must have a charge shut down feature when it gets hot...at 2a it aught to take 5 minutes to fully charge if not cause flames to shoot out the back.
 
I will keep on monitoring the bat temp while charging at home and in the car. But 2A supply should not be a problem. Rating of the supply means max amount of current it can "supply". If the source doesn't need that much, it will pull as much as it required. We just hope that once this requirement is met, battery will shut down.
 
IMO, I doubt it it would be the cable. I am using the 2.1A charger with a 15' USB extension cable into a 6' USB to micro into the Moto car dock.:eek: Both of the cables I purchased were the least expensive ones found on Amazon.

Amazon.com: RiteAV - USB A to Micro-B Cable 6 ft.: Electronics

Amazon.com: 15 Foot USB 2.0 Extension Cable: Electronics

Yes but at 21 feet of cord if your cheap cables have 26 or less gauge wires you could have added enough resistance (and through 2 different junctions) that you have lessened the supplied voltage to where you aren't getting as much charge as possible.

Remember, To charge the battery you must first have enough voltage differential to get the current into the battery. This is why I am using the standard moto cable. if I get another it will be the larger monoprice one with 24awg power wires. and Don't go through any extra connection. Remember Less is more.

I did fail to mention..as stated before..I to found the phone to be hot while gps turned on and charging with SC unit. The phone read 137 degrees. I am in Fla, it was a mild 96 outside with 180% humidity(not really). Is there a boiling point with the phone? Thinking 137 is high, could have cooked an egg on it. Seems normal temp is approx 80-90 degrees. If I am not getting 1a, don't really know if any higher would literally cook the phone?

mine hit 132 the other day, IIRC it should shut it down somewhere near 170. need to look up LI-Ion/polymer battery limits. But the phone most likely stops charging around 150 as a safety precaution.

A silly question, where/how do you read temp internal to DX?

I got a battery meter app that included it. Looking for one that does battery capacity in finer detail than 10% increments. That's too coarse for testing purposes. I drove 30 minutes the other day with GPS and phone and didn't even get a 10% rise. Or maybe, don't know for certain. It could have been 9.8% increase and I wouldn't see it.

Meanwhile. are any of you seriously streaming audio off the network as you drive on a regular basis? Damn. I just intend to use the audio out to the car stereo with MP3's I put on the memory card.

Just curious as that seems like trying to do too much at one time. Maybe its just me.
 
FYI guys. The Micro USB specification only allows for 500 mA of current. However, a device can accept more current if it is connected to a dedicated charger. The device itself, in such a case will limit the amount of current it can take in to 500 mA unless it sees a short in the data terminals with a total resistance to the device of no more than 200 ohms.

That said, I have two Scosche chargers that are rated at 1 A each. The data terminals are not shorted so the phone will only charge at 500 mA. I only played with this with my girlfriend's Incredible but on it, the battery status under the settings menu will tell you if its charging via USB or charging via AC. I would think its the same for the DX but I won't have mine until tomorrow so I can't say for sure.

I have done modifications to a few old chargers I have and verified that shorting the data terminal within the charger will cause the phone to charge under AC power. If you are not afraid to open up a charger and solder the connections on the board, its an easy mod. The Scosche chargers I have though are not easy to disassemble though but their form factor has not been replicated by other companies AFAIK so I simply soldered the data pins inside the USB connection itself and it works fine. Assuming the charger's specs are accurate, I should be getting a full 1A current to the phone. I would not recommend soldering the USB terminals themselves unless you are pretty good with soldering quickly. Extended application of heat can melt the plastic tab inside and you need to keep the solder small or it might prevent the USB cable from plugging in.

I actually posted this before in this thread but that was right before the forums had issues and the restoration was from a point in time before I posted it. There was a discussion in the Incredible section that provided the initial info and I found the USB specifications sheet in a subsequent search but I don't feel like finding it again at the moment.

I only state this because it is quite possible that many of you have chargers that don't have their data connections shorted so the phone may be accepting only 500 mA of current. If the status message is similar to the Incredible, it would be easy to check.
 
CK...makes sense...My SC unit does not appear to be charging any faster than the stock china unit. The SC unit does not charge the phone while running gps or animated weather radar. It does seem to keep the phone from dischr. I expected that almost doubling from 500 to 1000 would charge the phone is quick order. I put phone on charge with SC, unit screen off, for 1 hour and only charged 10%. That does not seem to be right? So...what you are saying sounds right to me.
 
Can't say for sure about Scosche since I didn't test it for that long, but PowerJolt2 should meet all the requirements such as 200ohm termination mentioned above. I had that charger with GPS off and it charges up very fast, 3x or 4x faster than from my laptop's USB port and at the same rate as OEM wall charger supplied with DX.

Regarding battery temperature, unfortunately I only got that widget today when our Jersey temperature dropped by 30deg. Through my morning 1hr30min trip and afternoon 1hr15min trip with GPS on and plenty of calls I was able to arrive at the end with 100% battery charge using 28/24 cable and PowerJolt2. Temperature never exceeded 37degC so I was nowhere near what you guys have seen. BUT, in the last couple of days when we had 100+ degF heat outside, my battery was charging up OK in the morning when it was cool, and not as good on a way back when battery cover felt way too overheated to the touch.
 
FYI guys. The Micro USB specification only allows for 500 mA of current. However, a device can accept more current if it is connected to a dedicated charger. The device itself, in such a case will limit the amount of current it can take in to 500 mA unless it sees a short in the data terminals with a total resistance to the device of no more than 200 ohms.

That said, I have two Scosche chargers that are rated at 1 A each. The data terminals are not shorted so the phone will only charge at 500 mA. I only played with this with my girlfriend's Incredible but on it, the battery status under the settings menu will tell you if its charging via USB or charging via AC. I would think its the same for the DX but I won't have mine until tomorrow so I can't say for sure.

I have done modifications to a few old chargers I have and verified that shorting the data terminal within the charger will cause the phone to charge under AC power. If you are not afraid to open up a charger and solder the connections on the board, its an easy mod. The Scosche chargers I have though are not easy to disassemble though but their form factor has not been replicated by other companies AFAIK so I simply soldered the data pins inside the USB connection itself and it works fine. Assuming the charger's specs are accurate, I should be getting a full 1A current to the phone. I would not recommend soldering the USB terminals themselves unless you are pretty good with soldering quickly. Extended application of heat can melt the plastic tab inside and you need to keep the solder small or it might prevent the USB cable from plugging in.

I actually posted this before in this thread but that was right before the forums had issues and the restoration was from a point in time before I posted it. There was a discussion in the Incredible section that provided the initial info and I found the USB specifications sheet in a subsequent search but I don't feel like finding it again at the moment.

I only state this because it is quite possible that many of you have chargers that don't have their data connections shorted so the phone may be accepting only 500 mA of current. If the status message is similar to the Incredible, it would be easy to check.

Exactly. I mentioned before that some cables that come with phones, have resistors in the cable so that the phone knows it can charge from it. Like you said spec requirements. This is also why that one micro-usb cable with the 24 ga wires is important to have. (or the orginal).

Didn't know they shorted the terminals on the USB A side, will have to check mine when I get home. Thanks.
 
Exactly. I mentioned before that some cables that come with phones, have resistors in the cable so that the phone knows it can charge from it. Like you said spec requirements. This is also why that one micro-usb cable with the 24 ga wires is important to have. (or the orginal).

Didn't know they shorted the terminals on the USB A side, will have to check mine when I get home. Thanks.

I tore apart an older Motorola Micro USB car charger and found the short was in the micro USB end of the cable. I could see a lot of chargers being built this way, but for a charger that has a USB port I would imagine they would short the connections within the charger so that one could use their existing data cables. When I tested the wall charger for the Incredible, the data ports in the charger are shorted. And it would have to be otherwise we would not be able to make a data connection with the included cable.
 
I tore apart an older Motorola Micro USB car charger and found the short was in the micro USB end of the cable. I could see a lot of chargers being built this way, but for a charger that has a USB port I would imagine they would short the connections within the charger so that one could use their existing data cables. When I tested the wall charger for the Incredible, the data ports in the charger are shorted. And it would have to be otherwise we would not be able to make a data connection with the included cable.

Yes I should have clarified. The short would be on the chargers usb terminal.

And BTW, my Scoche unit, does register as charging by AC. so it is shorted on both terminals. And again, need to have that 24awg wire or bigger.
 
Yes I should have clarified. The short would be on the chargers usb terminal.

And BTW, my Scoche unit, does register as charging by AC. so it is shorted on both terminals. And again, need to have that 24awg wire or bigger.

I wasn't familiar with the "awg" abbreviation and since you've been putting quite a bit of emphasis on it, I did a google search. I came up with the following page: American wire gauge - Wikipedia, the free encyclopedia

Basically it sounds like awg is a measure of cable thickness/circumference, is that correct? As the wiki entry states, as the awg number decreases, the thickness increases. Thus, a translation of what you're suggesting is "buy USB A to microUSB B cables with a thickness of 24 awg or thicker (lower awg number)". Right?


Can you please answer two questions:

1) Why are you recommending this? (aka, what is the benefit of having a thicker wire besides durability?)

2) How can you tell what the thickness of a wire is if the item listing doesn't specifically give the awg? I was browsing amazon, newegg: most listings don't specify the awg....

If you're feeling generous, perhaps you could provide some links to cables you deem suitable.... :)
 
What you need to look for is 28/24 cable; what it means that for data it uses 28 gauge wires and for power (+5V and GND) it uses a thicker 24 gauge wire. Two things about thinner versus thicker wire. First of all thin wire can not handle too much current and will overheat. If I'm not mistaken 28 gauge wire can handle a max of 1.4A while 24 gauge wire can handle about 3A. You always want to have margin of 2x when dealing with current rating. Another important point, thin wire will have a bigger voltage drop due to higher resistance (Voltage = Resistance * Current). So if you are passing the same amount of current through a wire that has higher vs lower resistance you will have a higher voltage drop. For example, if you are starting with 5V at the output of your charger and will have a big voltage drop, lets say 0.5V, you will end up with 4.5V going into your phone which is too low. The longer your usb cable and the thinner the wire (higher resistance) the more voltage drop you are going to have up to the point where its going to fall off below acceptable low limit threshold. This is just a basic EE101 :)

Regarding wire labels when buying online, they have to explicitly state that. If not, most likely it will be 28gauge typical thin usb cable wires. Dedicated USB chargers with a coiled built-in cable are probably thicker because those are AC charge cables rather than usb-pc cables. I also suspect that a short usb OEM cable from Moto we got with our DX is 28/24.

So far the only 28/24 usb cable I found was from monoprice which I previously listed in this thread, but here is a link again: For only $1.34 each when QTY 50+ purchased - USB 2.0 A Male to Micro 5pin Male 28/24AWG Cable w/ Ferrite Core - (Gold Plated) - 10ft | USB 2.0 Cables - Micro-B Type , this one is 10ft, but they also have 6ft and 3ft. Just have to look for a specific 28/24AWG rating.
 
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