Database Users

always on power

Does it harm to have the device connected the whole day either to the power outlet or to pc with the USB cable?

No, it doesnt matter very much how much you charge an Li-Ion battery, though it is best to use it a bit. (just my thoughts though). Being on power all day long cant really harm the device itself.

First of all, why do you want to do that?
Anyway, as whizz said, not much harm will be done to your phone, but just make sure your screen is off. Although not a common problem, there are reports that you can get burn-in (is this the right word?) for LCD screen (eg you can shadow-y image on your screen for displaying something too long).

cos when I am at the office I can keep my pda connected to my laptop the whole workin day

If you just wnat to have your phone connected to your laptop, for whatever reason, you can disable the USB charging for your phone.

i think not harm

the battery is lithium ion and leaving it on will cause no damage whatsoever. Its charging circuit will stop charge when its full anyway.
Too many people still live in the stoneage regarding batterys and think its like the old Ni-cad batts which didnt have a charging circuit and could over charge.
Leave it in all day, all night and for an entire year. It will do nothing to damage it.

weel I was just worried for overcharging, but if the circuit stops the charging when battery if full, it's ok then

dannyoneill said:
the battery is lithium ion and leaving it on will cause no damage whatsoever. Its charging circuit will stop charge when its full anyway.
Too many people still live in the stoneage regarding batterys and think its like the old Ni-cad batts which didnt have a charging circuit and could over charge.
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Click to collapse
If they are from stone age, you must be from Mars. Old Ni-Cad battery DO have circuits that prevent over charge. As a matter of fact, if you were to be using normal (slow) charger, you do not need any circuit to stop the charge. You can't charge a battery with the same voltage if the battery itself already had the same voltage. Go dig up your old physics book and read on the chaper on electricity.
Anyway, the common `battery knowhow` on NiCad batteries is that they need regular discharge to keep it on top shape. This is due to the fact that NiCad battery has the 'memory effect' (or oltage depression) that will cause it to work on their normal working voltages that they got used to (eg when it is plugged into a charger). Do a google on this if you are interested on lengthy explaination.
For the current Li-ion battery, the memory effect has been relatively 'concurred'. However, this does not mean you can have it on charger 24/7. Li-ion has its own aging process which is dependant on their normal working temperature (the cooler the better). Hence, having the battery pluged-in 24/7 is not a good thing (eg notice the relative raise in temperature of the battery while being pluged-in?). Do a google on this aging process.

How to change RTC battery ?

Each time when replacing battery date and time settings on my wizard return to default settings.
It seems CMOS battery on motherboard is dead.
Is there any way to change it and where to buy it?

Watchman said:
It seems CMOS battery on motherboard is dead.
Is there any way to change it and where to buy it?
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I don't believe that You're battery is dead. It's also heppend to me when my phone was new. Every time when I remove battery, I must set my clock and date again and again.

RTC Battery
nikolica said:
I don't believe that You're battery is dead. It's also heppend to me when my phone was new.
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My Wizard is about two years old and I have had not noticed it happening before .
I plan to open housing soon to look for such battery.

RE
If You need help for opening You're wizard look this article
http://www.pdagold.com/articles/detail.asp?a=274

you can't, really.
there's a "gold cap" small capacitor surface-mounted to the motherboard of your wizard top left. this retains enough charge to keep the RTC time right, and they wear out. replacing one is risky, as the heat from a conventional soldering gun may damage components - it's something i'd advise just living with.

RTC battery
landwomble said:
there's a "gold cap" small capacitor surface-mounted to the motherboard of your wizard top left. replacing one is risky, as the heat from a conventional soldering gun may damage components - it's something i'd advise just living with.
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Click to collapse
I can not live with it, used to swap batteries very often.
Can anybody suggest proper soldering tool and web shop where to buy such tool and capacitor.
I plan to open housing anyway because I want to replace housing for new.

RTC battery
landwomble said:
there's a "gold cap" small capacitor surface-mounted to the motherboard of your wizard top left. replacing one is risky, as the heat from a conventional soldering gun may damage components - it's something i'd advise just living with.
Click to expand...
Click to collapse
I can not live with it, used to swap batteries very often.
Can anybody suggest proper soldering tool and web shop where to buy such tool and capacitor.
I plan to open housing anyway because I want to replace housing for new.

Backup Battery in Wizard plus other devices
... my first post ... yes I'm a noob.
Answering to something that may be a little dated, but hopefully it will come in handy for someone.
Regarding the small backup battery in Wizard (plus likely other devices). This is indeed a small battery, and not a (gold cap) capacitor as suggested in literature/previous posts.
My device too suffered this loss in time with replacement of main battery.
I sourced the battery on line (only place I found it was at DigiKey). They were $2.75/ea. plus handling fee ($6.50) plus delivery ($8.00) and of course let's not forget those taxes.
http://dkc3.digikey.com/PDF/C081/P2214.pdf (- see Figure 1 on pdf)
It is a magnesium lithium ion rechargeable (Panasonic ML414RM/F9A - DigiKey P003CT-ND). I ordered 4 on-line (I have more than one Wizard, both suffering from the same plague - one is the one I do all the fun hacking on, and keep/use one as my main workhorse. What's fun is one is G3 and the other G4 so any ROM cooking I have tried Main OS and Extended, I can validate on both types ... sorry ... back to the battery)...
I replaced the one battery to test and it worked. It now works fine and retains the time/date settings.
Now the nore technical stuff. How was it determined that it was indeed a battery and not a capacitor. Well first of all looking at it (I work a lot with electronics). Secondly, after removing I measured a small voltage on the battery. I shorted the two leads, and measured again. The voltage began to rise again. If it were a capcitor, shorting the ends would eliminate any charge and that would be it. Being as it is a battery, it revives and returns to the pre-shorted voltage again (a capacitor would not do this).
Check your device and check the battery (if possible) before trying yourself. As I mentioned I do a lot with electronics and so I feel comfortable doing this.
For those who may want to attempt themself, a fine tipped electronics soldering iron can be used (from a Radio Shack or Source or any electronics hobby shop). Get low melting temperature solder (avoid the silver solders as these have higher melting points - don't want to cook the battery). Tin the battery leads before soldering to the board. Clean and re-tin the board itself. Avoid heating/over heating the battery too long as this will "cook" the electrolyte and dramatically shorten the battery life if not destry it. Very little on the board around this battery so less likely to do any damage to the board. If you do try .... GOOD LUCK

no one uses a capacitor for saving data(even time and date) except for desktop RAM but that's just cause it gets powered up all the time by the PS.
of course a capacitor is used for short-time memory.. but it's not more than 2-3 minutes. the only way you'd be able to keep it for a long term is to have a XuF capacitor with a small battery..
these batteries are known to die frequently due to voltage shocks and extra current. the phone itself has a safety mechanism in which if you connect it to different voltage sources, as long as they're in a thin range of voltages, will manage to charge.. but some of the inner mechanisms (such as that capacitor).. are burnt during charging.

Nandaly said:
... my first post ... yes I'm a noob.
Answering to something that may be a little dated, but hopefully it will come in handy for someone.
Regarding the small backup battery in Wizard (plus likely other devices). This is indeed a small battery, and not a (gold cap) capacitor as suggested in literature/previous posts.
My device too suffered this loss in time with replacement of main battery.
I sourced the battery on line (only place I found it was at DigiKey). They were $2.75/ea. plus handling fee ($6.50) plus delivery ($8.00) and of course let's not forget those taxes.
http://dkc3.digikey.com/PDF/C081/P2214.pdf (- see Figure 1 on pdf)
It is a magnesium lithium ion rechargeable (Panasonic ML414RM/F9A - DigiKey P003CT-ND). I ordered 4 on-line (I have more than one Wizard, both suffering from the same plague - one is the one I do all the fun hacking on, and keep/use one as my main workhorse. What's fun is one is G3 and the other G4 so any ROM cooking I have tried Main OS and Extended, I can validate on both types ... sorry ... back to the battery)...
I replaced the one battery to test and it worked. It now works fine and retains the time/date settings.
Now the nore technical stuff. How was it determined that it was indeed a battery and not a capacitor. Well first of all looking at it (I work a lot with electronics). Secondly, after removing I measured a small voltage on the battery. I shorted the two leads, and measured again. The voltage began to rise again. If it were a capcitor, shorting the ends would eliminate any charge and that would be it. Being as it is a battery, it revives and returns to the pre-shorted voltage again (a capacitor would not do this).
Check your device and check the battery (if possible) before trying yourself. As I mentioned I do a lot with electronics and so I feel comfortable doing this.
For those who may want to attempt themself, a fine tipped electronics soldering iron can be used (from a Radio Shack or Source or any electronics hobby shop). Get low melting temperature solder (avoid the silver solders as these have higher melting points - don't want to cook the battery). Tin the battery leads before soldering to the board. Clean and re-tin the board itself. Avoid heating/over heating the battery too long as this will "cook" the electrolyte and dramatically shorten the battery life if not destry it. Very little on the board around this battery so less likely to do any damage to the board. If you do try .... GOOD LUCK
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Click to collapse
The service manual speaks about a GoldCap 0,07F, 70Ohm, 3,3V (which isn't a normal capacitor) but mine looked like a small battery.
Mine was looking green because of some oxide on it. (caused by rainy jackets I thihk)
Is it really possible that the service manual is wrong? I thought there are also rechargable button cells...do you know for sure a regular lithium cell is ok?
(oh, my device is a prophet)

THIS IS A HIGH CAPACITY CAPACITOR also called super capacitor.
looking at what is printed GoldCap 0,07F, 70Ohm, 3,3V
F=Farad (capacitance values are normally specified in nano, micro, milli farads etc

I tried soldering on a broken USB connector in a wizard once but messed it all up, it seems they use some RoHS tin which makes it very difficult to make clean connections.

No! Not A Capacitor! Yes A Battery!
Folks,
This is indeed a battery in the HTC Wizard and NOT A CAPACITOR. A 0.07F capacitor would be physically several times larger than the phone itself.
So regardless of what is "printed" in the service manual, this is a small magnesium lithium ion rechargeable battery.
I have changed on 2 HTC Wizards (branded ATT Cingular 8125).
What I took out was exact identical to what I purchsed from Digikey (on-line as posted in my earlier comment)(and yes, the soldering is/was a tad bit difficult - if you do not know what you are doing).
Signed (Nandaly), B.A.Sc., P.Eng.

very strange battery problem no awnsers any where

Hi all
I have brought a sunny cube v7 (cheap tablet) and upon receiving this morning I went ahead and left it to charge for a few hours. When I came back it was fully charged so unplugged it imediatly powered off. I cracked it open and the battery it self is reading about 4v but after the protection circuit its reading about 2, the tablet itself is saying its fully charged but it won't turn on without charger . tried looking everywhere but all I could read was about not charging or a defunct battery. Any help is appreciated

Just give it back if it's under warranty?
Sent from my ST26i using xda premium

Thats the problem it wa from china so by the time i pay for shipping back there i might as well buy another one, it was only £40

Well, you seem to know about the protection circuit.
They can vary in coverage from over-discharge, over-charge and over-current.
Some of them will actually latch up once activated.
If you battery is reading 4 V there is no reason for the protection to be activated.
You can try bypassing the protection circuit.
That's living a bit dangerously, both as to your health and the health of the battery.
Still, as a proof of principle you could do it carefully.
You can buy a similar battery protection module on eBay for a couple of bucks.

Renate NST said:
Well, you seem to know about the protection circuit.
They can vary in coverage from over-discharge, over-charge and over-current.
Some of them will actually latch up once activated.
If you battery is reading 4 V there is no reason for the protection to be activated.
You can try bypassing the protection circuit.
That's living a bit dangerously, both as to your health and the health of the battery.
Still, as a proof of principle you could do it carefully.
You can buy a similar battery protection module on eBay for a couple of bucks.
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Click to collapse
Thanks for the info, I work as an electrical engineer repairing phones for insurance companies so i sort of know what im on about but never had this problem before and nobody at my work has faced it so thats a dead end. all I know about it is what ive read, I havent come across any information about this problem online. Do you know if i can just buy a similar protection circuit, or can I buy a bigger size battery (both in size and capacity) and will it still charge fully? thanks for the help!
Edit:
will my tablet tell me how charged the battery is if I remove the protection circuit?
2nd Edit, what controls the voltage to the battery, the circuit on the mother board or the protection circuit, as i understand it the protectionis only there in case the mobo gets a short, in other words the mobo says "im not taking any more voltage from you battery" then proceeds to shut down, is this the case? also with charging is it the mobo that starts the trickle charge +90% batt or isit the protection circuit, any help is greatly appreciated just want to get this sorted

The protection circuit is completely invisible and inactive except in cases of failure.
Charging circuits on the main board control conditioning, charging, terminating.
Determining percentage battery charge is a bit of voodoo based on voltage, temperature and estimated current load.
I don't know if any device (some? all?) are using Hall effect current sensors to measure instead of estimating.
I would think that a slightly bigger battery would not be a problem.
A smaller battery would not like getting charged too fast.

Replacing both the battery and the protective circuit shouldn't really be a problem. Are you measuring the voltage on the battery before/after the protective circuit - under load though? A battery without a load will always show a higher voltage than when "put to work". The protecive circuit itself does put a microscopic load on the battery, but I'm not sure if its enough for a decent load voltage read. if you have an old computer fan (probably won't go around if sub-5 volts, but should tolerate load long enough for a read) or something else that will "just work" off a 3.7v supply, I'd suggest you try that before shopping for parts.
Keep in mind, if buying a new protective circuit - it should be rated to comply with your tablet. Overcharge and overdischarge voltages are fairly similar across the board - but you'll want to look at Overcharge and overdischarge currents. Make sure these do not crash with the normal operational currents of the tablet. If the tablet for example, consume up to 2 amps under heavy load - you cannot use a protective circuit with an overdischarge current rating of less than 2 amps. If you did, it would trigger the protective circuit under normal (heavy) use. Same for overcharge current - make sure it is rated with a reasonable margin above what the stock charger delivers - otherwise the stock charger will pop the circuit.
I'd also advice getting one that is designed for the number of cells the current (or new) battery "pack" will be composed of. It will make putting it together much more simple and tidy.

[Q] modding a back cover for pogo like drop in charger, need some help.

I am trying to mod a back cover to expose the charging pins inside the phone, usually used for wireless charging modules, as external pads on the edge of the cover so I can drop it in a custom charging cradle. The design is pretty easy, the materials are trivial, and the spare back covers are cheap enough I can kill a couple while prototyping. But what I can't find is good documentation on the five spring pins/pads under the back cover.
Before anyone asks, I don't like wireless charging, it wastes to much power. That 30-40% charging inefficiency isn't just not transmitted, it is lost. Might as well revert back to incandescent bulbs rather than LED or compact florescent if you think wasting a little power per device isn't going to hurt anyone. Alright, done with my soapbox rant.
I don't know if the phone is expecting a slightly lower voltage on the wireless charging pins and is running the input through a step up converter to normalize the input voltage. I kind of assume that the wireless charging coils are matched to maintain voltage parity, but I would rather not risk burning up my phone testing it out. Then there are the other two pins, above the battery terminal, that I fantasize about being a set of usb data pins, though I am almost certain I am not that lucky.
I am also really bad at searching for this stuff so I am looking for a little help. I am not entirely sure if these pins are referred to as power pins/pads, test pins/pads, or something else entirely. My searches thus far just return lots of reviews and teardowns that don't talk about the input specs for the pins/pads. I haven't found any documentation online about using the pins for accessory development or anything else. I was hoping someone here has more details about these pins/pads.
Has anyone, who has experimented with the pins under the back cover, provide some guidance? Or has anyone found reference documentation for these pins?

No battery.. Any way to turn on?

Recently digged out my old Qtek 9000 from the closet, and want to get it turned on again, but i have no battery.. It had swollen up years ago, so i threw it out.
Is there any way i can get the device to turn on again? Plugging in the mini usb charger, and i get a steady red led on the device but not able to turn it on. I tried attaching a powersupply of 3.7v to the + and - min but still nothing..
Any tricks?

Replace battery. It can damage the device severely or worse.
Any swelling is a failure.
Do Not attempt to charge a failed Li!!!
Without the battery to supply enough current, it can not boot. The charger can't sink enough current for a boot up...

blackhawk said:
Replace battery. It can damage the device severely or worse.
Any swelling is a failure.
Do Not attempt to charge a failed Li!!!
Without the battery to supply enough current, it can not boot. The charger can't sink enough current for a boot up...
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Where to find a battery in the EU though?

Don't know. Sorry. Li's have a limited self life too of about 3-4 years max.

blackhawk said:
Don't know. Sorry. Li's have a limited self life too of about 3-4 years max.
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Oh.. Guess its a goner by now then. What a shame. Thanks for your input!

Da9L said:
Oh.. Guess its a goner by now then. What a shame. Thanks for your input!
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You can find or adapt a battery if you put some time into it... depends if it's worth it to you.
I have a 12yo flip top ruggedized phone that still boots

So to get the device to turn on with a another battery of the same voltage.. Should i only need to connect the two pins on each end of the pins on the device ?

Da9L said:
So to get the device to turn on with a another battery of the same voltage.. Should i only need to connect the two pins on each end of the pins on the device ?
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If there's only 2 pins, yes. The polarity must be correct!
Soldering to the mobo van be tricky if you're not proficient at doing it. Not the place to learn! The mobo landings can easily be destroyed by excess or prolonged heat. Prolonged is measured in seconds like 1-3 @ 725F with well tinned tip using 60/40 or better 63/37 lead based rosin core solder only. A tin or bottle of rosin flux can be useful.
You may only get one shot at it...solder pad landing repairs are even more difficult.
It wire is used, very thin gauge stranded only and always pretinned.