Sprint store employee claims: car charger works 3x faster

**jeeplj8** · 11-03-2010, 03:07 PM

So I was in the Sprint store and the store employee tells me that the car charger charges an Evo 3x faster than a wall charger.

So the question is: how true is that stetement?

**seraphemz** · 11-03-2010, 03:08 PM

Lol...he must have been trying really hard to get some commision.

**Verdes8891** · 11-03-2010, 03:09 PM

ummm, my guess is it would charger a little bit faster, if onyl because the voltage produced by the car would be greater then your wall outlet and home. But as far as 3x faster, i dont know about that.

**xtn** · 11-03-2010, 03:32 PM

Originally Posted by Verdes8891

ummm, my guess is it would charger a little bit faster, if onyl because the voltage produced by the car would be greater then your wall outlet and home. But as far as 3x faster, i dont know about that.

Um... Your car produces about twelve volts and your wall outlet at home should be around 110-120 volts.

**seraphemz** · 11-03-2010, 03:45 PM

Originally Posted by xtn

Um... Your car produces about twelve volts and your wall outlet at home should be around 110-120 volts.

depends where he lives...lol..

**mmcnamara43** · 11-03-2010, 04:10 PM

Originally Posted by seraphemz

depends where he lives...lol..

well here in the states, the car produces 12v and home about 120v...just saying

**workindev** · 11-03-2010, 04:20 PM

Actually, both are going to be converted to 5V DC per the USB power spec.

The included wall charger is rated at 1A, so if the car charger is rated at 3A it would charge 3x faster. I highly doubt that it is rated at 3A, however, as that would heat the battery up considerably while charging and would be a safety risk.

**clairegrrl** · 11-03-2010, 04:39 PM

My car charger is actually 3x slower.

claire

**treotraveler** · 11-03-2010, 04:47 PM

I think the DC charges 4 and a 1/2 times faster in a Kenworth BIG TRUCK only because I have 4 BIG batteries, and a battery in the reefer unit on the front of my reefer.

Not scientific at all, just a wild guess......

**Caitlyn McKenzie** · 11-03-2010, 04:57 PM

Originally Posted by workindev

Actually, both are going to be converted to 5V DC per the USB power spec.

The included wall charger is rated at 1A, so if the car charger is rated at 3A it would charge 3x faster. I highly doubt that it is rated at 3A, however, as that would heat the battery up considerably while charging and would be a safety risk.

It won't draw 3A, even if it's there. If it were possible to draw more than 1A for charging, HTC would have shipped a wall charger capable of it. (And people using iPad chargers would be raving about the charging speed differences)

**truslide** · 11-03-2010, 06:57 PM

Originally Posted by vincent law

(and people using ipad chargers would be raving about the charging speed differences)

rotflmfao

**deaofly** · 11-03-2010, 09:21 PM

Lol that made me lmao cuz its true about it being 3x slower

**xpanmanx** · 11-04-2010, 06:27 AM

In my car, I have a Kensington PowerBolt 2.1a USB power source/charger, and a modified USB cable which tricks my EVO into thinking it's on an AC charger. So......my EVO charges fastest in the car.

In the house, I have a 1.2a wall-wart USB power source/charger. Not too shabby either. But the charger in the car definitely outpaces it.

**frankiepapa** · 11-04-2010, 06:50 AM

Not sure about exact times and such, but I picked up a car charger from a non-corporate Sprint store for $10 and I think it was an AT&T branded micro usb and it is very fast....I can get from 20% to 80% from a trip from NJ to Brooklyn (40 minutes)..would recommend the AT&T car charger in an instant

**Mustachio** · 11-04-2010, 07:43 AM

Regardless, a slower charge is better for the battery.

**Caitlyn McKenzie** · 11-04-2010, 08:15 AM

Guys, all you need is a 1 amp charger. Period. Anything over 1 amp will not go faster, and anything under 1 amp will charge slower than the HTC AC charger. I know you all like to provide your own experiences, but there's really no reason to discuss it further, because this is the exact specs and design used on the EVO. It cannot, and will not draw more than 1 amp.

**Gekko** · 11-04-2010, 08:41 AM

these people working in Sprint stores don't have PhDs. take everything they say with a grain of salt.

81 · 11-04-2010, 08:56 AM

agreed with gekko.

i have a 1A usb adapter for my truck. without testing, i would assume it's the same speed as the 1A wall adapter

**NicksGarage** · 11-04-2010, 02:09 PM

I tested this with mine using an app that actually shows how many mah are being used. The car chargers were less than half of the wall charger consistently. My EVO charges much faster with the wall charger than it does with any USB charger, car or otherwise regardless of the charger's rating.

**npark** · 11-04-2010, 03:26 PM

Folks... it does NOT matter what the power SOURCE is.

DC 12v, DC 18v, AC 110v, AC 220v... all of that matters not a whit. There are only two things that matter:

DC 5 volt is being fed to the phone. All else is irrelevant wherever it comes from. Hence, why voltage doesn't matter--the phone can only use DC 5 volt.

Amperage: this determine how much "juice" is being drawn. Now folks, the power is not "pushed" to the device. The device "draws" the power from the available power source. The phone will draw only up to 1 amp. It was designed that. So, if you plug the phone into a DC 5V/10Amp source, it will only draw 1amp. If you plug the phone into the iPad's wall charger which is a 5v/2a source, it will still only continue to draw 1 amp. However, if you plug the phone into your computer's USB port, USB ports only have .5 Amp of 5v DC current. As a result, the phone can only draw .5 amps (or 500 miliamps) since that is all that is available.

Back the original question: Can a car charger charge 3x faster than the wall charger? Impossible. The phone will only draw 1amp of power, it matters not a whit if more juice is available.

**Trust** · 11-04-2010, 05:16 PM

my car charger is as fast as my wall charger.

**xpanmanx** · 11-05-2010, 02:29 AM

Something else to think about: A crap 5vdc 1a power source may put out less amperage than the label would lead you to believe.

**xpanmanx** · 11-05-2010, 02:32 AM

Originally Posted by Vincent Law

Guys, all you need is a 1 amp charger. Period. Anything over 1 amp will not go faster, and anything under 1 amp will charge slower than the HTC AC charger. I know you all like to provide your own experiences, but there's really no reason to discuss it further, because this is the exact specs and design used on the EVO. It cannot, and will not draw more than 1 amp.

By chance do you have any documention which describes the tolerance of the current-limiting system?

**xpanmanx** · 11-05-2010, 02:40 AM

Originally Posted by Trust

my car charger is as fast as my wall charger.

You bet it is, if it's kicking the EVO into fast charge, which allows the handset to draw ~1a. Want to know for sure? Check out the Spare Parts app, battery info page.

A normal USB connection is limited to ~500ma, and unfortunately a great many chargers fit the spec. When the EVO senses a USB connection, it kicks down into slow charge.

You can hack a cable or a whole charger such that the EVO kicks into fast charge, but if the charger can't supply the 1a current, your fancy soldering will be for naught.

**xpanmanx** · 11-05-2010, 02:49 AM

Originally Posted by npark

However, if you plug the phone into your computer's USB port, USB ports only have .5 Amp of 5v DC current. As a result, the phone can only draw .5 amps (or 500 miliamps) since that is all that is available.

When it detects a 4-wire USB connection, the EVO will also limit its current draw to 500ma to protect the supply circuit. Just on the off chance that some cheapo motherboard could fry itself sending too much amperage down the traces to the USB port, you understand

The hardware hacks I've been referring to involve tying pin 2&3 of a USB cable together. Obviously, you must never use such a cable with a data-capable USB port,but when used with a properly designed power source, all kinds of goodness happens.

(I take no responsibility if anyone tries this and blows up their junk. YMMV CYA TYVM)