Chargers for 350/650

[frquixote]

Thanks for all the replies. None of my existing AC chargers/adapters would work with the PRS-650, so I gave in to Sony's extortion and bought their charger for the PRS-350/650.

I'm now looking for a new battery pack sinced my Socket Mobile Power Pack doesn't work with the Sony PRS-650.

[Juggle4Evr]

Originally Posted by elemenoP;

For example, elcreative, you say that 500-2000mA should work fine. What if the charger is rated 3000mA? Does such a charger exist? Would it fry the device, or would the device "take what it needs?"

The device takes what it needs concerning the mA. What is really dangerous is if the voltage is too high.

[elcreative]

In the spirit of plain english... the wrong charger won't even fit your reader... USB (mini and micro-USB) is a standard... if you use the wrong charger then you will be forcing the wrong plug into the socket... and if forcibly jamming the wrong plug in, doesn't give you a hint that it's wrong then I don't know what will...

And to respond to elemenoP... a 3000mA charger should still work fine but I have never come across a USB 3000mA... I guess a 100A might fry it by simply treating the micro-socket as short-circuit but since such a thing doesn't exist...

Boxcorner... you're just being a smartass... for a start the groups you mention are hardly contributors (or readers) of this forum... the people of this forum (considering it's title) are "possibly" able to read but that doesn't preclude an inability to understand basics... Oh, and where does the US enter into it... a prejudice of yours?

[elizilla]

I've done a lot of work with electricity. I wired my own garage and it hasn't burned down yet. And I've installed more electric gadgets into my motorcycles than anyone else I know. I do understand the different between volts and amps and watts. But I'm still frustrated by the eReader charger situation.

[polly]

At the risk of putting my foot in my mouth:

1. Hold up intended cord.
2. Look on both ends. Does one end have a standard USB end? Does the other end look like it might plug into the reader? If the answer to both of these questions is yes, continue to the next step. If the answer is no, try again with another cord.
3. Pick up wall wart (little adapter with prongs that fit into the wall and a place where you can plug in a USB cable.
4. Use magnifying glass to ensure that voltage rating on wall wart matches voltage rating of your house. If the answer to this question is yes, proceed to next step. If the answer is no, pick up another wall wart.

If you successfully make it this far in the list, you're ready to plug in your reader. The options are that it will work or it won't work. If it charges, all is good. If it doesn't charge, start working through the list again. So far mine has worked with my Palm Pre official cable, my Retraks cable, the cheap generic cable to charge my Pre at the office, and the microUSB adapter for my battery pack. My battery pack had no issues charging it either. In fact, every cable I've tried so far has worked as expected. Other than the fact that Sony recharging used to be confusing, I'm not sure why it's so confusing now. It appears to follow all of the rules that USB devises follow.

[elizilla]

Polly,

I suspect you're fortunate in having cables kicking around that actually worked. Perhaps all micro-USB power cords work fine. I don't have any other devices in my collection of gadgets, that charge from micro-USB, so I have been testing what happens when I plug the cord that came with my 650, into a variety of generic USB chargers. And my results have been the opposite of yours. So, yup, still confusing.

Here's what I posted in an earlier thread:

I have a Griffin USB wall charger I use to change my Sansa MP3 players, but it didn't work with my PRS650. The specs on this say it is 5v, 1000mA.

Neither did my Belkin USB car charger - the PRS650 saw it as USB, but didn't kick over to charge mode. This one is labeled 5v, 1A output with a 12v input. The cig lighter port I had it plugged into would have been putting out a little over 12v, because that's what motorcycles do, but I wouldn't think that would matter.

The USB port on the Alpine stereo in my truck didn't even look like USB to it, it was like it wasn't plugged in at all. I have no idea what specs that port puts out, but the stereo was on so you'd think it was live.

[polly]

Originally Posted by elizilla

Polly,

I suspect you're fortunate in having cables kicking around that actually worked. Perhaps all micro-USB power cords work fine. I don't have any other devices in my collection of gadgets, that charge from micro-USB, so I have been testing what happens when I plug the cord that came with my 650, into a variety of generic USB chargers. And my results have been the opposite of yours. So, yup, still confusing.

Here's what I posted in an earlier thread:

I have a Griffin USB wall charger I use to change my Sansa MP3 players, but it didn't work with my PRS650. The specs on this say it is 5v, 1000mA.

Neither did my Belkin USB car charger - the PRS650 saw it as USB, but didn't kick over to charge mode. This one is labeled 5v, 1A output with a 12v input. The cig lighter port I had it plugged into would have been putting out a little over 12v, because that's what motorcycles do, but I wouldn't think that would matter.

The USB port on the Alpine stereo in my truck didn't even look like USB to it, it was like it wasn't plugged in at all. I have no idea what specs that port puts out, but the stereo was on so you'd think it was live.

Hmm, I thought we were talking about the cable part of this equation versus the wall wart. The USB port on your truck wouldn't have looked like a USB to your reader. That's for you to connect music sources to your truck stereo. I doubt it's designed for charging, but your truck might have been willing to play music from the reader. I've not tried to charge mine of of a lighter adapter (12V), mostly because it only needs charging every other week or so and I manage to schedule charging around car trips. Inside the house, mine has charged off of the adapter that Astak gave me with my PEz last year, my Palm Pre adapter, both of my battery pack chargers (one doesn't hold a charge anymore but still has two USB ports for charging), and a surge protector that has USB connections. In fact, I can't think of anything where it refused to charge. If the adapter is compliant with universal USB requirements, it should work. Some adapters with two USB ports only give half of the charge to each port, especially if you have two devices plugged in at the same time. Not sure why it didn't work with your Griffin, but that's the only one on your list where I'd expect it to work.

At the risk of being painfully obvious, how are you deciding that it's not charging? Are you waiting for the screen message to change or are you looking for the red light to come on next to the stand by slider? When you plug it into a wall, you can still use it as a reader. The only indications mine shows that it's charging are the tiny red light and a change in the battery icon at the bottom of the screen.

[Dixiemsala]

Good Lord! Would someone please answer in plain English? Will a Kindle charger hurt the 350?

[boxcorner]

Originally Posted by elcreative

... you're just being a smartass... for a start the groups you mention are hardly contributors (or readers) of this forum... the people of this forum (considering it's title) are "possibly" able to read but that doesn't preclude an inability to understand basics... Oh, and where does the US enter into it... a prejudice of yours?

I am sorry if my comment upset you - no offence intended. The point that I was endeavouring to make, apparently not very well and I agree rather sarcastically, is that I don't think it's safe to presume that all contributors (or readers) of this forum know as much as you do about electricity, or current USB connector standards. As regards your presumption about any prejudice of mine, once again I accept that my point wasn't very well made. Actually, I was partly educated, lived and have worked in the US. Even though the majority of the contributors (or readers) of this forum appear to be located in the US (you haven't revealed your location), the PRS-n50s are of course marketed worldwide, so I don't think one should presume that all users will have encountered that type of USB connector before, say in connection with chargers for their cell (mobile, portable) phones. For example, my Nikon camera uses a similar tiny USB connector for data transfer, but whilst their thicknesses are the same, their widths are similar but slightly different.

Originally Posted by frquixote

... I gave in to Sony's extortion and bought their charger ...

I bought a dedicated charger from amazon.fr that cost me 8.10 EUR which is approximately 11.22 USD

http://www.amazon.fr/Chargeur-Sony-B...sr=1-1-catcorr

[astra]

Originally Posted by Dixiemsala

Good Lord! Would someone please answer in plain English? Will a Kindle charger hurt the 350?

Accordingly to what some people report, yes, you can charge 350 with Kindle charger.

[elcreative]

In plain English... read comments above such as Polly's... does the plug fir the Sony... if so try it... The only way a PSU will damage your reader, is if you drop it on the reader as long as you don't force the wrong plug in place. You could also try looking at the PSU as it is standard to have the voltage and current written on the PSU... if it's 5-5.15v and current is over 500mA then plug it in...

Originally Posted by Dixiemsala

Good Lord! Would someone please answer in plain English? Will a Kindle charger hurt the 350?

[Quilathus]

The USB standard since has standardised what "dumb" chargers should implement for charging without IC circuitry.
Traditional USB requires the device to tell the host that it wants to draw more power, a negotiation of sorts. However, many chargers simply pump out 5V without any digital circuitry. So how does a device know if it can draw more than the 100ma mandatory minimum if it gets no response to its challenge to draw more current?
According to the USB standard, the +D and -D lines of the USB should be shorted out with no more than 200ohms (?) of resistance. This would tell the device that it can draw as much as it wants from the dumb charger. One thing to note is that if a charger is built properly, it will give out current in its rating in milliamps and no more without failing. The device charging, on the other hand, will just draw whatever amount it needs, or whatever the charger gives it and all should be fine.
According to anecdotal evidence, this works as I have personally shorted out +D and -D lines on a dumb charger and the Sony eReader does not complain about no power supply being detected. If you happen to have a charger with a USB-female port (i.e. having no built-in cable ending with a usb-male plug), and it doesn't work charging your Sony eReader (because the +D and -D lines floating and 0V), then you have two options:

1. Either void the charger's warranty, risk electrocution or whatever: You can open up the charger and just solder either an appropriately valued resistor across the middle +D -D solder joints of the USB plug, or just apply a blob of solder to short it out and be done with it. However, besides the risks involved with opening up mains-connected devices, some simply don't allow you to open them, so you're left with:
2. You can buy a cheap USB male-to-female adapter cable (easily found on eBay for a dollar or less). Carefully stripping the insulation, identify the wires connecting +D and -D lines, short them out and use your preferred insulator to cover your hack job... and now you've made yourself a charger cable than can be used for any standards compliant device that complains about detection or charges very slowly on your charger.

Unfortunately, you have pesky products which do expect voltage on the +D and -D lines, such as Apple products. In this case, commonly accepted values for +D and -D are 2.0V and 2.8V respectively. Like above with 1) or 2), you can either modify the charger, or create your own cable (I recommend doing this). My experience is that an un-shorted potential of +3V on both +D and -D (independently) still works to charge the Sony eReader. In that case, you can use 47K and 33K (in that order) resistors in a voltage divider fashion to obtain approximately the correct voltage, and using the (independent!) voltage dividers, apply the divided voltage onto the +D and -D lines and hopefully the device doesn't complain (it doesn't for me). This should be relatively safe as the high resistance values prevent too much current from flowing, and that very little power is drawn from the +D -D lines since only voltage needs to be detected...

Of course, if you don't want to solder, wait for cables to arrive, or aren't willing to apply voltage onto the USB data lines, then perhaps buying a cheap microusb charger that is known to work (like blackberry chargers etc.) is for you.

That should clear up the charger confusion about different chargers working, why some don't, cable issues (some chargers with included cables have +D -D lines floating!) etc.

PS: Current is just the capacity of the charger to deliver electrons at 5V . The only problem you need to consider is what voltage the charger is outputting, and if it can deliver it at a high enough current that satisfies your requirements (500ma for many applications, 1A for "boosted" charging circuits, 2A for the iPad etc.). If the device can draw more, but the charger can't output more, then only the charger's maximum current rating will be delivered and your device won't be damaged (it just won't charge as fast) - unless the charger's circuitry design is poor and it overheats/fails thereby risking whatever was connected to it.

[elemenoP]

>>Good Lord! Would someone please answer in plain English? Will a Kindle charger hurt the 350?<<

Seems the answer is: try it out, don't force it, it will either work or not, but it won't damage your 350.

[SeaBookGuy]

Originally Posted by dkb

I use my Kindle charger to charge my new PRS-350. It seems to work. Is the any reason I shouldn't use it?

This isn't so long a thread that you would've missed this post?

[elizilla]

Originally Posted by polly

Not sure why it didn't work with your Griffin, but that's the only one on your list where I'd expect it to work.

At the risk of being painfully obvious, how are you deciding that it's not charging? Are you waiting for the screen message to change or are you looking for the red light to come on next to the stand by slider? When you plug it into a wall, you can still use it as a reader. The only indications mine shows that it's charging are the tiny red light and a change in the battery icon at the bottom of the screen.

I just plugged it in again to double check my results. The red light does not turn on. The screen goes to a spot where I cannot continue to read - it says USB is connected, and gives a message that says "Charging stopped". The fine print at the bottom says "The reader is unable to charge as no power supply is being detected. Please check that the charger is plugged in and switched on or that the USB cable is correctly connected."

I've ordered an aftermarket Kindle 3 charger kit off Amazon, that contains a generic USB wall wart and car charger. With luck it contains the resistors/solder described in this thread, and I won't have to open it up and do that myself - my soldering is terrible! If it works to charge both the Sony reader and my Sansas, then I'll use those instead of the ones I have now. Maybe it will even work to charge my phone.