If your pandora doesn't charge correctly please read this


asimov-solensan

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Well it has been a while since i wrote here last time. I read the forum daily but I feel I don't have anything interesting to add.

Just wanted to comment some tests that I have made lately:

I had the original pandora charger and it broke. Therefore I bought this one compatible with PSP. It's a woxter 220v to USB and it comes with a dongle with multiple plugs for iphone, psp, nds, etc ... (sorry I'm unable to find the model on the web)

It made strange things since the beginning sometimes pandora stopped charging (red light turned off) at eighty-something sometimes at seventy-something. But the drama begun when I left the console to completely discharge. Then it stopped charging at 40% or even it detected that battery was fully charged at 2%.

So I tried a really old transformer I had at my work's storehouse. It's a toshiba thing that gives 5v and enough current, and it had the same connector (and same polarity), it is huge as a brick and I don't have any idea where this thing comes from, but hey!, it does the work. I charge the pandora with it and all runs smooth (stops charging around 95%).

So what is the difference between the chargers. I made the following experiment:

I have got three chargers:

Toshiba - 5v/0,5A - Pandora charges correctly.

Woxter - 5v/1A - Pandora becomes crazy

Apple - 5v/1A - Not tested yet with pandora (this is a 220 to USB charger, physically very similar to the woxter one)

Tested the three of them on two different multimeters (and a very precise ones), and the results are:

Toshiba: 5.103v exactly

Woxter: 5.040v to 5.070v It is very unstable but the diference is just tenths of millivolts

Apple: 5.089v exactly

There goes my theory.[sPECULATION] Charging circuit on he pandora is very picky and it becomes idiot if the voltage is not stable.[/sPECULATION]

I know that there is people (I recall porg for instance) that had similar problems, I want to ask them if they can get access to a good multimeter and see the output of their chargers.

By the way I'm running SuperZaxxon 1.54 here and my battery is almost three years old, it's not strange that it doesen't reach 100% of charge.
 
I'm more inclined to think its to do with the fact that the Woxter charger is only providing 1A.  

Try switching to low power mode when charging with the Woxter, (and leaving it that way until the charge light goes out)   I suspect you'll see a much better result.

- Neelix
 
hrm...  I misread that as 5A... 

What I do know is that neither of the chargers that came with mine was less than 2A...  and that the USB input isn't enough to charge the pandora properly if I'm using a large amount of power. (eg wifi on, and CPU heavy application or game running)

- Neelix
 
Well, instead of measuring using a multimeter you should use an oscilloscope and look at what the chargers put out.

I could bet that the problematic one has quite a lot of higher frequency spikes instead of a cleaner dc voltage.
 
Yep, I can confirm that cheap AC Adaptors which provide bad signals can be problematic.

I have some cheap chinese PSP adaptors at home which even make the touchscreen almost completely useless when connected.

I wouldn't be surprised if these will lead to charging issues as well.

I don't think small voltage changes are the problem, but an unclean (not properly switched) signal with a lot of spikes.
 
I'm glad to say that my original PSP charger works perfectly with pandora and so is the adaptor that came with the USB "dock" (branded thrustmaster) for PS3 joypads.

The "original" pandora charger is also working perfectly, of course ;)
 
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I know that there is people (I recall porg for instance) that had similar problems, I want to ask them if they can get access to a good multimeter and see the output of their chargers.
Hi asimov-solensan!

Read your post just now. Correct, I had originally reported here, later linked it there ("charging my Pandora unattended to full load never works! Always find it at around 60-80%, instead of 100%, or at least near 100%. sysinfo logs proof it."), and in the same thread my various own attempted tests failed (various wall chargers and USB chargers, also did some rudimentary checks with the voltmeter (only standalone, not under load!)) plus further tests instructed by WizardStan (isopropyl alcohole cleaning, battery out/pause/in, reading out charging chip calibration with i2cget) the ended there ("Repeated that battery out/in test at medium charge, and again I had:

40% (1575 mAh) —> battery out, wait ~20 minutes, battery in —> 46% (1791 mAh). Will do the treshhold-altering [with i2cset] test on the weekend, when I get time for it.").

 

Maybe one day I'll get some time to do the metering tests and the charging chip altering tests.
 
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I get sometimes problem recharging, but it's all the time du to heat. I fell the heating by putting my finger between start button and right nub. And when I have this overheating is most of the time because I'm recharging + compiling + networking with a USB dongle pluged directly. And in fact, I think most of the heat I feel come from the USB activity and the dongle itself. Using the same dongle on a USB Hub I don't have the issue.

Just my observation...
 
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