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A dozen USB chargers in the lab: Apple is very good, but not quite the best

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Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#21

Post by ladyada »

rhizome wrote: post #14
mhb wrote: post #2

Would be nice to know how the adafruit charger does: http://adafruit.com/products/501

I bought two for ~$3 apiece at Fry's a few months ago. One is OK, the other was and is DOA. The one that mostly works sometimes requires jiggling in the jack to make contact, but generally they are a garbage, F-, would not buy again product.

Hi Rhizome, adafruit does not distribute the specific USB charger we carry at Frys - sorry to hear you had a bad experience with them but it was certainly not the same one from the adafruit shop the parent poster was referring to!

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#22

Post by brigade »

kmfrk wrote: post #16
acgourley wrote: post #15

The lesson here is that if you don't want to pay for an official apple charger, do not buy a counterfeit one just buy any name brand one with the right wattage rating.

And even with Apple chargers you risk using a charger with the wrong wattage (iPad charger vs. iPhone/iPod IIRC).

The only risk you take in that scenario is that your device may not charge as fast as you expect (or at all, if in use.) Same with the 3 different wattages of MagSafe adapters.

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#23

Post by nostromo »

GuiA wrote: post #18

" Since the designers of the Apple charger went to a great deal of effort to build a high quality charger, I conclude they must not consider voltage sag worth worrying about. Or, more interestingly, maybe they built this sag as a feature for some reason. In any case, the chargers lose points on this." I'm not versed in the arcane arts of EE— could anyone give me a basic definition of voltage sag? And would there be a…

It's exactly what it sounds like: a short-term dip in voltage.

I'm not sure why any end user would care about this, unless they are using a device with no battery.

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#24

Post by philh »

mseebach wrote: post #4

It's off-topic, but I've been trying to figure it out for a while: I have a two-port "Gear4" USB charger with swappable plugs, so it's great for travelling. However, my new work BlackBerry won't accept a charge from it, complaining about it being too low powered - however, the Gear4 charger says it's 2A, the BB charger is 750mA. Does anyone know what's the deal?

On a similar note: I have a second generation iPod nano. Years ago I took a spare cable for it and cut the data wires, hoping to be able to plug it into a computer to charge while still being able to play music. (I saw this tip somewhere online.)

It worked with my brother's iPod classic (maybe 5th gen?), but not my nano; later I saw something on Adafruit about how the iPhone needed specific voltages on the data pins to charge, and I figured that was what was going on.

But recently, I got a battery pack, which can output to microUSB, iPod, or some other things. It works with my iPod, the same one I had years ago. But the cables it came with have swappable ends, I think 2.something mm jacks. At any rate they only have two points of connection. Here's what it looks like: http://i.imgur.com/8TliS.jpeg

So, how does this work? As far as I can tell, this should be exactly the same situation as a standard USB-iPod charger with its data cables cut, but it's not behaving the same.

It's possible I'm getting some details wrong, but can anyone shed some light on this?

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#25

Post by rhizome »

ladyada wrote: post #21
rhizome wrote: post #14

Earlier quoted context omitted.

I bought two for ~$3 apiece at Fry's a few months ago. One is OK, the other was and is DOA. The one that mostly works sometimes requires jiggling in the jack to make contact, but generally they are a garbage, F-, would not buy again product.

Hi Rhizome, adafruit does not distribute the specific USB charger we carry at Frys - sorry to hear you had a bad experience with them but it was certainly not the same one from the adafruit shop the parent poster was referring to!

This appears to be what I purchased, and it looks exactly the same:

http://www.frys.com/product/6740515

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#26

Post by protomyth »

rhplus wrote: post #3

This link just wouldn't have been quite as clickable: A dozen USB chargers in the lab: HP is the best .

I'm not so sure about that. HP and USB aren't exactly in people's search list as frequently as Apple. Beyond that, I clicked wondering if Apple was selling a general USB charger and not an iPad / iPhone accessory.

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#27

Post by joenathan »

philh wrote: post #24
mseebach wrote: post #4

It's off-topic, but I've been trying to figure it out for a while: I have a two-port "Gear4" USB charger with swappable plugs, so it's great for travelling. However, my new work BlackBerry won't accept a charge from it, complaining about it being too low powered - however, the Gear4 charger says it's 2A, the BB charger is 750mA. Does anyone know what's the deal?

On a similar note: I have a second generation iPod nano. Years ago I took a spare cable for it and cut the data wires, hoping to be able to plug it into a computer to charge while still being able to play music. (I saw this tip somewhere online.) It worked with my brother's iPod classic (maybe 5th gen?), but not my nano; later I saw something on Adafruit about how the iPhone needed specific voltages on the data pins…

The data pins may be shorted or bridged on your battery packs' cable.

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#28

Post by jopt »

nostromo wrote: post #23
GuiA wrote: post #18

" Since the designers of the Apple charger went to a great deal of effort to build a high quality charger, I conclude they must not consider voltage sag worth worrying about. Or, more interestingly, maybe they built this sag as a feature for some reason. In any case, the chargers lose points on this." I'm not versed in the arcane arts of EE— could anyone give me a basic definition of voltage sag? And would there be a…

It's exactly what it sounds like: a short-term dip in voltage. I'm not sure why any end user would care about this, unless they are using a device with no battery.

Right on. Perhaps the company we deride for not letting us remove the battery could be excused for not optimising for devices with no battery.

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#29

Post by makomk »

rhizome wrote: post #25
ladyada wrote: post #21

Earlier quoted context omitted.

Hi Rhizome, adafruit does not distribute the specific USB charger we carry at Frys - sorry to hear you had a bad experience with them but it was certainly not the same one from the adafruit shop the parent poster was referring to!

This appears to be what I purchased, and it looks exactly the same: http://www.frys.com/product/6740515

Just because it looks the same doesn't mean it has the same internals, especially with cheap made-in-China kit.

Re: A dozen USB chargers in the lab: Apple is very good, but not quite the best

#30

Post by ladyada »

rhizome wrote: post #25
ladyada wrote: post #21

Earlier quoted context omitted.

Hi Rhizome, adafruit does not distribute the specific USB charger we carry at Frys - sorry to hear you had a bad experience with them but it was certainly not the same one from the adafruit shop the parent poster was referring to!

This appears to be what I purchased, and it looks exactly the same: http://www.frys.com/product/6740515

I assure you that just because two adapters look the same do not have any relation to the insides. (After all, counterfeit Apple adapters look the same as genuine ones, but you wouldn't think they are the same on the inside after reading this article.) The black plug casing is a common molding style used by many factories - but its the electronics inside that count :) The best way to know if they are identical is to look for the UL certificate number, those are unique to each design.

We have a photo of our label here http://www.adafruit.com/images/large/ID501label_LRG.jpg

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