Develop Bugs

400mAH ZAP POrtable Energy BAttery for the Universal

Just got the 4000mAH ZAP Portable Energy battery.
The provided adapters do NOT have a Standard USB-to-mini 5-pin USB all male adapter which is required for charging the Universal from the ZAP battery. You'll require this piece which costs a few dollars only.
Specs here:-
http://www.zapworld.com/PE/ZAPd14.asp
Under Additional Info you can see that the USB output current is 700mA with 4 - 6 V. The AC adapter output DC voltage and current to the Universal is 5V 1A. Hence, the ZAP battery is usable although the compatible PDA list does not show.
Here:-
http://www.zapworld.com/PE/pe_pr.asp
I'm using it. USE AT YOUR OWN RISK!!

RE
Sorry, subject should read 4000mAH instead of 400mAH
Can the mod please correct it. Thanks

RE : 4000mAH is NOT at 5V
Just to make some clarification
The 4000mAH is at 3.7V
So, at 5V the mAH would be much smaller

[Q] Charging Speed - Different from a/c than from USB?

So I was wondering: is there a difference in charging speed between the a/c wall charger and charging from my computer's USB port? Also, what's the difference between different chargers? For example, the Desire comes with a charger that puts out 1 amp. My girlfriend's BlackBerry has a micro USB charger as well, but the output is 700 mAh, or 0.7 amp. I've seen chargers ranging from 500 mAh (0.5 amp) to 1200 mAh (1.2 amp). How does this equate to charge time? Does it even? Or does the phone regulate the charge rate?

Benny_L said:
So I was wondering: is there a difference in charging speed between the a/c wall charger and charging from my computer's USB port? Also, what's the difference between different chargers? For example, the Desire comes with a charger that puts out 1 amp. My girlfriend's BlackBerry has a micro USB charger as well, but the output is 700 mAh, or 0.7 amp. I've seen chargers ranging from 500 mAh (0.5 amp) to 1200 mAh (1.2 amp). How does this equate to charge time? Does it even? Or does the phone regulate the charge rate?
Click to expand...
Click to collapse
You've pretty much answer your own question!
The current supplied by a charger/USB port determines how fast it can charge the battery, which is why the wall charger (1amp) charges much faster than a PC USB port (0.5 amps).
Regards,
Dave

It's almost completely logical.. say you have a 1.5A battery (1500mA) and a 500mAh charger (ie USB) then it will take 3 hours for it to charge but with a 1000mAh charger it will take an hour and a half.
Can't really explain it more than that, so hth.

Well , Yes and No
This is only partly true ......
If you charge it on the PC , max output is 0.5 amps , and data is possible while charging .
Now with Desktop and car charger , the amp can be anything the manufacturer likes but you have to keep the following in mind :
USB Specs state the following :
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In Battery Charging Specification,[32] new powering modes are added to the USB specification. A host or hub Charging Downstream Port can supply a maximum of 1.5 A when communicating at low-bandwidth or full-bandwidth, a maximum of 900 mA when communicating at high-bandwidth, and as much current as the connector will safely handle when no communication is taking place; USB 2.0 standard-A connectors are rated at 1500 mA by default. A Dedicated Charging Port can supply a maximum of 1.8 A of current at 5.25 V. A portable device can draw up to 1.8 A from a Dedicated Charging Port. The Dedicated Charging Port shorts the D+ and D- pins with a resistance of at most 200Ω. The short disables data transfer, but allows devices to detect the Dedicated Charging Port and allows very simple, high current chargers to be manufactured. The increased current (faster, 9 W charging) will occur once both the host/hub and devices support the new charging specification.
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So if your Desire ( Yes , the Desire supports these specs ) detects the short , it will switch to fast charging mode otherwise it will limit the charging current .
Unfortunately , there's no way to know , just by looking at a charger, if it respects the specs or is just a low cost 5V powersupply . I've encountered quite a few ( mostly lowcost) desktop and car chargers that are rated between 1 and 2 amps , but still take bl**dy ages to charge the phone . Checking those with a measuring tool , you usually see the data pins are "Not Connected" instead of being shortened :-(((
Final Word .... don't try to save some money on a cheap charger , you'll regret it Genuine HTC works great , others do the same , but don't expect a $1 charger from Hongkong or whereever to do it !

These are the theoretical specs. Keep an eye on charger efficiency ratings and battery charge absorption won't be 100% in any case. Also bare in mind the charge is not linear, it will trickle after approx 80-90% with this phone.
-----------------------------------
- Sent via my HTC Desire -

th3 said:
These are the theoretical specs. Keep an eye on charger efficiency ratings and battery charge absorption won't be 100% in any case. Also bare in mind the charge is not linear, it will trickle after approx 80-90% with this phone.
-----------------------------------
- Sent via my HTC Desire -
Click to expand...
Click to collapse
Ya, I noticed the charge slows down considerably for the final 10-15 %
I find myself charging my Desire more than I actually use it, lol.

I found now the answer to this problem: I use a Nokia charger (5v and 890 mA) with a microusb adapter. You can find one on eBay at ~2$
Now it takes about 2 hours from 20% to 100%
Lets hope nothing wrong happens to my precious Desire

look here for a method to charge at ac speed from usb, explains a few things too.

Highest output car charger

Is this the highest?
http://www.seidioonline.com/product-p/pmc.htm
Post links if you know of higher ones, thank you.
Sent from my ADR6400L using XDA App

There are 2.1A usb adapters, but I don't think microUSB can take advantage of it. The one you linked is a 1A, which is the same as the wall charger HTC gave with the phone. I'm currently using a 1A usb adapter in my truck.

Ok that's probably what I'm looking for then. Are there wall chargers greater than what came with the phone that I can take advantage of?

Your best bet would be to try the USB adapters made for iPads. The Apple products can utilize the 2.1A chargers with their sync cables, but I'm not sure if a microUSB cable can though. I have some 2.1A wallchargers from some of my Apple products, I'll test them later and let you know what I find out.

http://www.verizonwireless.com/b2c/...ryDetails&archetypeId=12299&accessoryId=46370

I just got an Enercell from Radio Shack with dual usbs. Max output is 2.5A divided between the two ports.
http://www.radioshack.com/product/index.jsp?productId=11329448
on sale now for only $14.99. Seems to be of good quality.

The Motorola rapid chargers rock.

Guys, unless you mod the usb adapter 5V spec, you aren't doing squat with a "high power" adapter. The device has an input impedence that will draw a certain amount of current at 5v., and that's it.
Standard battery: 1400 mAh
Time to charge: 4 hrs (according to manual)
That's 1400/4 = 350 mA.
Most adapters on the market spec more than that, they're usually 500 mA or above. And again, unless you boost the volts, you're not going to be able to push more than 350 mA or so.
So don't waste you're money.
On the other hand, if your going to share a car outlet with another device like mp3 or ipod, then yeah, you'll need a higher output, two port, adapter.
Edit: It just occurred to me that if you're using the phone heavily while charging, then yeah you may need more than 500 mA. My currrent widget shows the phone can draw another 250 mA or so during use. That plus the charge totals to around 600 mA. But depending upon design, the phone may not be able to pull in all 600 mA. A test with a current meter would be real interesting.

The charger shipped with the Thunderbolt is a 1 Amp charger.
If I use a 500 mA charger the Current Widget shows a +450mA charge current. However if I use the 1A charger, I get a charge current of about +850mA.
Given that the google navigation gobbles over 400mA when running, you need a car charger with greater than 500mA capacity of you want the phone to charge at the same time.
Sent from my ADR6400L using XDA App

boingboingbilly said:
The Motorola rapid chargers rock.
Click to expand...
Click to collapse
Good to hear, I ordered one today for $11 on ebay. I had heard other people say they liked that one too.

Ecomaniac said:
Guys, unless you mod the usb adapter 5V spec, you aren't doing squat with a "high power" adapter. The device has an input impedence that will draw a certain amount of current at 5v., and that's it.
Standard battery: 1400 mAh
Time to charge: 4 hrs (according to manual)
That's 1400/4 = 350 mA.
Click to expand...
Click to collapse
You're making the incorrect assumptions that the charging rate is constant, and charging is 100% efficient. Li-ion batteries can be charged at up to a 1C rate (i.e. 1.4A for a 1400 mA cell). Add the power drawn by the phone itself, and a 1.8 Amp charger might not be unreasonable (1.8 A is the specified limit for micro USB connectors). Whether the phone will actually do a maximum rate charge, I don't know.
This, from a TI Application Note (Google for SLAA287, board won't let me post links):
A Li-Ion battery charging process consists of three stages:
· Slow Charge: Pre-charging stage using current of 0.1C
· Fast Charge: Constant current charging stage using current of 1C
· Constant voltage charging stage
During the slow charge stage, the battery is charged with a constant low charge current of 0.1C, if the battery voltage is below 2.5V. The slow charge stage is rarely used during the charging process of a Li-Ion battery.
The fast charge (constant current) and constant voltage charging are the most important stages during a recharge process. Most Li-Ion batteries have a fully charged voltage of 4.1 or 4.2V.
The battery is first charged with a constant current of 1C until a battery voltage reaches 4.1 or 4.2V. The firmware continuously checks the charging current by sensing the voltage at the current sense resistor (Rsense) and
adjusts the duty cycle of PWM output from the MCU. The battery's voltage is checked frequently.
Whenever found the battery's voltage reaches 4.1 or 4.2V, the charger will switch to constant voltage charging mode. The battery is then charged with a constant voltage source at a fixed battery voltage of 4.1 or 4.2 V...When the charging current falls below 0.1C, the charging process must stop.
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Click to collapse

Monoprice has Cig to USB(1A) chargers and the USB to Micro cables in multiple lengths(I ordered 6' ones) for far cheaper than you will find anywhere else

mike.s said:
You're making the incorrect assumptions that the charging rate is constant, and charging is 100% efficient. Li-ion batteries can be charged at up to a 1C rate (i.e. 1.4A for a 1400 mA cell). Add the power drawn by the phone itself, and a 1.8 Amp charger might not be unreasonable (1.8 A is the specified limit for micro USB connectors). Whether the phone will actually do a maximum rate charge, I don't know.
This, from a TI Application Note (Google for SLAA287, board won't let me post links):
Click to expand...
Click to collapse
very useful, thanks!

walbuls said:
Monoprice has Cig to USB(1A) chargers and the USB to Micro cables in multiple lengths(I ordered 6' ones) for far cheaper than you will find anywhere else
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Click to collapse
I second monoprice.

I tried bunch of cig to usb car charger and none matched advertised output... They all showed Charging (USB). I now use AC inverter and it charges just like a wall charger.

eccenpix said:
I tried bunch of cig to usb car charger and none matched advertised output... They all showed Charging (USB). I now use AC inverter and it charges just like a wall charger.
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Click to collapse
I suspect you need to find one which properly follows the USB Battery Charging Specification. That link is to the most recent version, which came out on 7Dec2010 (remember Pearl Harbor!). Version 1.1 is easier - a Dedicated Charging Port is indicated by shorting together the data lines (the two middle conductors on a full sized USB connector. By doing so, it indicates the device may try to draw up to 1.8 A of current (although a dedicated charging port is allowed to limit the current to less than that, it must provide at least 1.5 A).
I bought a cheap USB hub with 5 ports, used an exacto knife to cut the traces going to the data lines (the middle two) on all the ports, and then shorted them together on each port. It's now no longer a USB hub, but a USB charger with 5 ports I can used to charge stuff (phone and Bluetooth, quite often). The AC adapter which it came with does 2 Amps. My Thunderbolt says "Charging (AC)" when plugged into it.
So, if you can open up one of your adapters, just solder a jumper between the middle two contacts (make sure they're not connected to anything else).

Just got the Rocketfish premium microUSB at Best Buy and it has a captive coiled cord and a USB port. TBolt says "AC plugged" and reads +670 mA.

Good choice on the Motorola Rapid Charge - I've burned through 3 other cheap car chargers trying to keep my phone alive while using Google Nav and this is the first one to work!

i have the rapid motorola one on amazon

lippstuh said:
i have the rapid motorola one on amazon
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Click to collapse
+1 Works great! Battery widget usually shows about +800mA while only charging. Real close to the wall charger

will charge battery faster if phone shut down? and how does FAST CHARGE work ??

as we know , for example the wall charger has output of 1A.
and battery capacity is 1750 mAh , so in theory , it should be 100% charged in 1750 mAh / 1000 mA = 1.75 hours.
but consider something like cable resistance or whatever , i think it should be fully charged like 2.5 hours or so ...
but what strange is, i have an old wall charger which was come from with Nexus S , only has 700 mA output and the new one came with Galaxy Nexus which has 1 A output. but my application , DX power booster , charge estimated time shows exact same with both 700 mA and 1 A ... i just don't get it as they have different output current ...
and i think , when charger is plug in, phones runs on power source directly from charger which will decrease the current goes to battery i think , so will the battery charging be short if i shut down my phone when it charges ?
and as for a USB , 5 V and 0.5 mA , which is only half of wall charger , then why does FAST CHARGE will make it as shortly as wall charger ?
because i think , no matter it is on or off , it doesn't alternate the fact that USB still only has 500 mA output ...
maybe they are stupid questions ... but i just failed my physics back the time i was student ...

My Gnex charges WAY faster when it's turned off. A few times I've left the house and realized I forgot to charge my phone overnight so I turn it off, put it on the car charger and usually have a useable charge even if it's a fairly short trip.

If you're phone is off, it's not using the power it's getting from the charger, therefore it will reach 100% faster
Sent from my Galaxy Nexus using xda premium

qtwrk said:
as we know , for example the wall charger has output of 1A.
and battery capacity is 1750 mAh , so in theory , it should be 100% charged in 1750 mAh / 1000 mA = 1.75 hours.
but consider something like cable resistance or whatever , i think it should be fully charged like 2.5 hours or so ...
but what strange is, i have an old wall charger which was come from with Nexus S , only has 700 mA output and the new one came with Galaxy Nexus which has 1 A output. but my application , DX power booster , charge estimated time shows exact same with both 700 mA and 1 A ... i just don't get it as they have different output current ...
and i think , when charger is plug in, phones runs on power source directly from charger which will decrease the current goes to battery i think , so will the battery charging be short if i shut down my phone when it charges ?
and as for a USB , 5 V and 0.5 mA , which is only half of wall charger , then why does FAST CHARGE will make it as shortly as wall charger ?
because i think , no matter it is on or off , it doesn't alternate the fact that USB still only has 500 mA output ...
maybe they are stupid questions ... but i just failed my physics back the time i was student ...
Click to expand...
Click to collapse
wall charging is only faster because your phone is not using battery while charging, so of course it would take a shorter time to reach full battery, thus appearing to charge 'faster'.
Fast charge is fooling the phone into thinking your charging from a wall socket instead of a usb, as when in usb mode it uses some of the power to transfer files between the phone and computer, so when in fast charge mode it only charges and cant be used to transfer files. this is from what i understand so far

vincentistan said:
wall charging is only faster because your phone is not using battery while charging, so of course it would take a shorter time to reach full battery, thus appearing to charge 'faster'.
Fast charge is fooling the phone into thinking your charging from a wall socket instead of a usb, as when in usb mode it uses some of the power to transfer files between the phone and computer, so when in fast charge mode it only charges and cant be used to transfer files. this is from what i understand so far
Click to expand...
Click to collapse
But what I don't understand is, no matter you transfer files or not, it doesn't alternate the fact that USB output is still 500 mA...
Sent from my Galaxy Nexus using xda premium

When you activate Fast charge you fool the USB port to think it doesn't have a communication device attached, and thus can deliver up to 1.5A on the port (dependent on port type). The phone charges faster when turned off because it doesnt use any power itself. The charging board on the phone will always control how much current you can recieve at all times (even when off).
Taken from Wikipedia.
Charging ports and accessory charging adapters
The USB Battery Charging Specification of 2007 defines new types of USB ports, e.g., charging ports.[46] As compared to standard downstream ports, where a portable device can only draw more than 100 mA current after digital negotiation with the host or hub, charging ports can supply currents above 0.5 A without digital negotiation. A charging port supplies up to 500 mA at 5 V, up to the rated current at 3.6 V or more, and drop its output voltage if the portable device attempts to draw more than the rated current. The charger port may shut down if the load is too high.
Charging ports exist in two flavors: charging downstream ports (CDP), supporting data transfers as well, and dedicated charging ports (DCP), without data support. A portable device can recognize the type of USB port from the way the D+ and D- pins are connected. For example, on a dedicated charging port, the D+ and D- pins are shorted. With charging downstream ports, current passing through the thin ground wire may interfere with high-speed data signals. Therefore, current draw may not exceed 900 mA during high-speed data transfer. A dedicated charge port may have a rated current between 0.5 and 1.5 A. There is no upper limit for the rated current of a charging downstream port, as long as the connector can handle the current (standard USB 2.0 A-connectors are rated at 1.5 A).
Before the battery charging specification was defined, there was no standardized way for the portable device to inquire how much current was available. For example, Apple's iPod and iPhone chargers indicate the available current by voltages on the D- and D+ lines. When D+ = D- = 2V, the device may pull up to 500 mA. When D+ = 2.0 V and D- = 2.8 V, the device may pull up to 1000 mA of current.[47]
Dedicated charging ports can be found on USB power adapters that convert utility power or another power source — e.g., a car's electrical system — to run attached devices and battery packs. On a host (such as a laptop computer) with both standard and charging USB ports, the charging ports should be labeled as such.[46]
To support simultaneous charge and sync, even if the communication port doesn't support charging a demanding device, so called accessory charging adapters are introduced, where a charging port and a communication port can be combined into a single port.
The Battery Charging Specification 1.2 of 2010 [12] makes clear, that there are safety limits to the rated current at 5 A coming from USB 2.0. On the other hand several changes are made and limits are increasing including allowing 1.5 A on charging ports for unconfigured devices, allowing high speed communication while having a current up to 1.5 A and allowing a maximum current of 5 A.
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Charging using 2.0 Amp

I have External battery pack which gives off 2Amp trough USB instead of 1Amp like The Original Charger will it actually use 2Amps? or Tell the battery to use only 1. Is it even safe to charge the battery at twice the amperage or find Extinguisher handy.

You can use that port. The phone has current limiting software / hardware to prevent it from getting to much juice. It will regulate its self to around 1 amp even with a 2 amp supply.