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Accessories Chargers compatibility

Alonzzo2

Well-Known Member
Nov 23, 2009
106
3
Up until now i had the samsung galaxy (i7500), which i charged using the usb port.
Can i charge the desire z with any usb charger? or do i need the specific usb charger of the desire z? what about the car charger? can i use my old nokia car charger?
 
Up until now i had the samsung galaxy (i7500), which i charged using the usb port.
Can i charge the desire z with any usb charger? or do i need the specific usb charger of the desire z? what about the car charger? can i use my old nokia car charger?
I just upgraded from an I7500 also and yes both the wall charger and the usb cord from the I7500 work with the Z.
 
Upvote 0
You can charge it with a usb port, but your charge time will be a lot longer than it would be if you use the high voltage wall charger it comes with. Think two hours vs five or so hours.

*High current wall charger.

----

[Rant about USB]
USB2 's max voltage is 5volts.
Max current is 500mA, and is divided into 5 units / devices.
By default, a device can get 100mA maximum, if it doesn't need more, or is a so called 'dummy' device (USB light or fan etc).
An intelligent device can tell a computer to give it more slots, to the maximum of 5, giving it 500mA.

This is why some devices, i.e a portable HDD, may require 2 USB cables.
This gives it the possibility to ask to take 10 units, or 1A.
If that is not enough, external power is needed.

For USB3, one unit is 150mA and there are 6 slots, giving the maximum of 900mA.

The Desire Z will get between 100mA and 500mA from an USB2 port.
[/Rant]


The chargers seem to be rated for 5Volts/1Amp, and the battery is 3.7V / 1300mA.
Lithium-ion batteries can be charged with a current of 1C, where C is the current it takes the battery one hour to be depleted (1300mA, or 1.3A here).

A optimum charger would be 1C, 1.3A, and would take around 1hour 10minutes.
A 1Amp charger would take 1h35min.
A 500mA charger (USB2 5 units) would take 3h 5min
a 100mA charger (USB2 1 unit) would take around 15h 35min

Now, these are not the true charging times obviously (1hour 10minutes full charge would rock!), but should give some scale to how the currents matter :)

Also, the important part about the info on chargers:
VOLTAGE is important,NEVER EVER use a charger with a higher VOLT rating than 5 (FIVE) VOLTS. NEVER. NO.
CURRENT is just how much the charger can GIVE, the charging circuits 'ask' for current. More is better, too much is just a waste of money.
 
Upvote 0
Do you know why there's a 1A limit?

That was me having a "senior moment" :oops:

The USB 2.0 specs are 5V/0.5A (500mA). I have slapped myself on the back of the head several times. ;)

All computer USB ports conform to this, as do all generic (and properly designed) chargers. We'll ignore the ultra-cheap Far East knock-offs as nobody who values their smartphone should be buying one of those. :) However the important figure is the voltage - that should never exceed 5V. Amperage is secondary.

Given the above restriction, lithium-ion batteries incorporate (or should - see "ultra-cheap Far Eastern knockoffs above) sophisticated protection circuitry which prevents over-charging. The battery itself says "enough" when it's near full capacity. One cannot overcharge a Li-Ion (or Li-Poly) battery pack... provided it's manufactured correctly.

Modern devices also limit the current draw as required. A smartphone with a near-depleted battery will draw the maximum current (amperage) provided by the charger until it reaches near-full capacity, at which time it says "enough!" and prevents further charging. If the device is powered on, this will result in gradual depletion until such time as a threshold is reached, at which time charging will re-commence to the previous point. There's no "trickle charging". A device may ask for 2.0A, but if the charger can only provide 1.0A then 1.0A is all that it will receive. Note that the device is in control, not the charger.

TL:DR version:
Amps don't matter, voltage does.
If its 5V or less... good. More? Bin it!
Less amps than stock = slower charging time
More amps than stock = same charging time

Real World(tm) example:
My Sony Xperia Z takes ~2hrs to charge from "low battery" (20%) to 100% with stock 1.5A charger.
It takes the same time to charge using a 2.1A car charger, as the handset itself limits the current draw to 1.5A.
It requires over 3hrs to reach 100% using the HTC 1A charger on the other bedside table.

I hope this clears up any confusion?
 
Upvote 0
That was me having a "senior moment" :oops:

The USB 2.0 specs are 5V/0.5A (500mA). I have slapped myself on the back of the head several times. ;)

All computer USB ports conform to this, as do all generic (and properly designed) chargers. We'll ignore the ultra-cheap Far East knock-offs as nobody who values their smartphone should be buying one of those. :) However the important figure is the voltage - that should never exceed 5V. Amperage is secondary.

Given the above restriction, lithium-ion batteries incorporate (or should - see "ultra-cheap Far Eastern knockoffs above) sophisticated protection circuitry which prevents over-charging. The battery itself says "enough" when it's near full capacity. One cannot overcharge a Li-Ion (or Li-Poly) battery pack... provided it's manufactured correctly.

Modern devices also limit the current draw as required. A smartphone with a near-depleted battery will draw the maximum current (amperage) provided by the charger until it reaches near-full capacity, at which time it says "enough!" and prevents further charging. If the device is powered on, this will result in gradual depletion until such time as a threshold is reached, at which time charging will re-commence to the previous point. There's no "trickle charging". A device may ask for 2.0A, but if the charger can only provide 1.0A then 1.0A is all that it will receive. Note that the device is in control, not the charger.

TL:DR version:
Amps don't matter, voltage does.
If its 5V or less... good. More? Bin it!
Less amps than stock = slower charging time
More amps than stock = same charging time

Real World(tm) example:
My Sony Xperia Z takes ~2hrs to charge from "low battery" (20%) to 100% with stock 1.5A charger.
It takes the same time to charge using a 2.1A car charger, as the handset itself limits the current draw to 1.5A.
It requires over 3hrs to reach 100% using the HTC 1A charger on the other bedside table.

I hope this clears up any confusion?

Dang! I just bought an ultra-cheap Far East charger. Cost less than a pound including free delivery (cheaper than a single stamp in my country; how is that even possible).

http://www.ebay.com/itm/Universal-U...rger-EU-US-Plug-For-Smart-Phone-/161451846121

Know what kinda trouble one could get charing with those? It said 2A, so I figured it'd be fine.
 
Upvote 0
Know what kinda trouble one could get charing with those? It said 2A, so I figured it'd be fine.

Worst case scenario? You could send mains AC voltage and current straight into your device. Not good for it or anything nearby.

I know a bargain is always tempting (I'm a Scotsman!), but when it comes to electricity I won't use anything that doesn't have at least a 'CE' mark and cert. number stamped on it. That stuff can kill.
 
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Thanks for the reply. I am adding this link for later reference.

http://lifehacker.com/5957596/tests-show-why-you-should-stay-away-from-knockoff-usb-chargers
http://www.bbc.co.uk/news/uk-27390466

"Mark Gardiner, joint lead officer for product safety at the Trading Standards Institute (TSI). (...)
Battery overheating
A central part of the safety concerns experts have with products bought online focuses on generic chargers - advertised as being compatible with a number of devices.

Mr Gardiner says that because different devices require different levels of charge, generic chargers run the risk of putting too much energy into a device, causing the battery to overheat.

Branded chargers are less likely to cause that problem because they are specifically designed for each particular device, Mr Gardiner said.
 
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