Using a different battery to test a Samsung N900V

[Spork Schivago]

Hello,

I replaced the charging port on a Samsung N900V. I believe the new charging port is bad. However, I wanted to know if I could use a different battery, made for a different phone, to test. I see where the positive and negative terminals are labeled on the Samsung battery (which is 100% dead). The battery is a 3.8V Lithium Ion battery (12.16 Wh). The other one I want to put in there is a 3.7V Lithium Ion battery (6.11 Wh).

They both have 4 pads and the + and - are both in the same spot. Would it be dangerous to plug the smaller battery into the phone? Just to see if the phone turns on?

Thanks.

[diif]

Re: Using a different battery to test a Samsung N900V

It should be fine. Alternatively unplug the USB board and plug in the charger. You should then be able to measure to see if you are getting 5v.
Did you replace the whole board or just the USB connector ?

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

On this phone, I replaced the whole charging board. It was only 5$ with free shipping or so.

Let's say I unplug the USB board from the main logic board and plug in the charger. Where would I measure the 5v?

The customer said she doesn't have the "super charger" that normally comes with the phone but she's using a normal micro-USB cable. She said she has used the normal micro-USB cable for a while and it has always charged the battery fine. The phone was dropped, the screen cracked. Eventually, the only way she could get it to charge was to move the micro-USB cable a bit, now that doesn't work. We've verified the micro-USB cable is good and charges other phones.

Even putting in the other battery, I don't get the phone to turn on but maybe it doesn't have enough amperage. It's much smaller, almost half the physical size of her normal phone.

I'm tempted to take my programmable PSU and set the amperage to something like 3 AMP and the voltage to 3.8VDC and put the probes on the + and - terminal, where the battery normally goes.

The flex cable for the charging port has a billion little pins. It's one of those weird ones like Apple's use, where you put it over the connector on the board and just push down, to snap it in. I've made sure it's probably connected and no pins were bent.

[diif]

Re: Using a different battery to test a Samsung N900V

I'd measure on the back of the micro usb connector.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

That's where I wanted to measure diif, but the pins are just too many and too close together. Keep in mind, this isn't just a micro-USB charging port. It has a place for the micro-USB and a place for the other part of the super charger.

I know this isn't the best way to check, but I removed the battery and plugged in the working charger and just tested where the battery terminals were, you know what I'm saying? I got 0VDC there so I'm assuming the charging port they sent me is bad. What do you think?

Thanks.

[diif]

Re: Using a different battery to test a Samsung N900V

Ahh, I have a microscope so measuring the pins wouldn't be a problem.
The extra bit is USB3 not the super charger bit. The actual size for the micro USB is the same.

You're just showing there is nothing to the battery not that the USB or board is faulty.
It's possible it's faulty or it's possible something else is at fault.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

Ahh, I have a microscope so measuring the pins wouldn't be a problem.
The extra bit is USB3 not the super charger bit. The actual size for the micro USB is the same.

You're just showing there is nothing to the battery not that the USB or board is faulty.
It's possible it's faulty or it's possible something else is at fault.

From the video I watched, if the charger is plugged in but the battery is removed, those pins there should show voltage. You're right though, it could be more, but I'm going to take a risk and try to get a replacement sent. Based on what the customer said, I'm thinking it's just a bad replacement port. I bought it off e-bay. Samsung refused to sell me one and said I had to send the phone in to have them "fix" it.

Tomorrow, when my wife gets home from work, I'll throw some voltage with a higher amperage (maybe 3 or so?) on those pins and see if we can get it turn on. I'll feel awful if the e-bay seller sold us a working charging port and I sent it back.

Wish I had a microscope. We can't even find the magnifying glass right now. I want one of the nice ones, that I can hook up to the PC and stuff. Do you think it's worth the investment? There's many times I wish I had one. One that could take pictures or something as well, that'd be great. With a built in light.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

So, is there a super charger? That's how she referred to them. I have to admit, it's my wife that normally fixes the cells. I don't even own one. She just doesn't do the soldering stuff and USB ports, that's normally my job. She does cracked screens and the like. She did this USB port because it was easy but when it didn't work, she brought it to me. Kinda like the blind leading the blind, eh?

**EDIT: You know what, being USB3, I bet it can provide more amperage. I bet it can charge the battery quicker and maybe that's why she was referring to it as a super charger. We just assumed that was the name. I've seen this connector before but never realized it was USB3. Thanks for pointing this out to me diif.

[diif]

Re: Using a different battery to test a Samsung N900V

It's Samsung's adaptive fast charging nothing to do with USB3. The S6 has it but only a regular micro USB socket. Something in the phone tells the charger to give more juice. It should still charge without the extra current just not as fast.

I have used a micro usb to female USB adapter with an unsoldered USB connector plugged into that. You can then check the continuity without the risk of shorting anything. You only need to test the 5v and ground.

Excuse the mess !
I went with a "proper" stereo microscope as I felt it best, the optics, stand, working over the piece rather than looking up at a screen. The screen near my workbench can show schematics rather than the work piece. It looks cool too

It has certainly helped me immensely when repairing SMD stuff. I can comfortably measure the pins on any device and can do repairs that weren't practical to do. I'm pretty sure a USB microscope would do the job, any aid in seeing the work greatly increases the ease and speed of work.

[diif]

Re: Using a different battery to test a Samsung N900V

Using one of those cheap USB voltmeters will also help in this kind of work to show if any current is being drawn.
I have a micro USB cable here, I plug it in and my phone shows it as charging yet it only seems to allow about 0.25A whatever device it's plugged into. Just swapped it for a new cable and its pulling 0.92A now.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

It's Samsung's adaptive fast charging nothing to do with USB3. The S6 has it but only a regular micro USB socket. Something in the phone tells the charger to give more juice. It should still charge without the extra current just not as fast.

I have used a micro usb to female USB adapter with an unsoldered USB connector plugged into that. You can then check the continuity without the risk of shorting anything. You only need to test the 5v and ground.

Excuse the mess !
I went with a "proper" stereo microscope as I felt it best, the optics, stand, working over the piece rather than looking up at a screen. The screen near my workbench can show schematics rather than the work piece. It looks cool too

It has certainly helped me immensely when repairing SMD stuff. I can comfortably measure the pins on any device and can do repairs that weren't practical to do. I'm pretty sure a USB microscope would do the job, any aid in seeing the work greatly increases the ease and speed of work.

How much did your "proper" stereo microscope cost you? Also, is that a BGA rework station off to the left there that I see? If so, which make and model do you have?

There's always a chance it's not the actual port but something on the charging port board / module as well. I'll test the continuity for the gnd and 5VDC wires. I'll take a micro-USB cable and just cut it so I have access to the wires. Then I'll plug that in and figure out what wire is what and what pin is what.

[diif]

Re: Using a different battery to test a Samsung N900V

It was second hand off ebay, I won it for about £120 but the seller was cool and let me have it for £100 when I turned up. Seeing up close is good, add in 3D and its awesome. Something a USB microscope doesn't do.
It is and it says Scotle on it, not sure if it's genuine or not but it has quality heating plates.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

It was second hand off ebay, I won it for about £120 but the seller was cool and let me have it for £100 when I turned up. Seeing up close is good, add in 3D and its awesome. Something a USB microscope doesn't do.
It is and it says Scotle on it, not sure if it's genuine or not but it has quality heating plates.

I got a Scotle! Mine's an HR460C (the C just means it comes with a really really cheap camera and a really really cheap monitor).

My HR460 came with really cheap heating elements so I replaced them with some Elstein's. It costed some money but I think, for me, it was worth it. It was just the preheaters, because the BGA work is all done with air, not the ceramic heating elements.

I might have to replace my first BGA component in the near future, an MT8202. If I do have to replace it, do you think if I start a new thread on it, you could maybe help me figure out how to do it? I believe I know how to properly set the temps and stuff, but the previous owner says the temps we set aren't really the same that the datasheets recommend, if that makes sense. He says it's more of an art and over time, I'll get the hang of it. I figured I could practice on some old motherboards first before I started on this TV I got here.

[diif]

Re: Using a different battery to test a Samsung N900V

Yes, plenty of practice on scrap board first.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

When you run across a heatsink that's glued onto the chip, what do you do? This appears to be some sort of maybe ceramic thermal compound that's also an adhesive. I might in incorrect in that assumption though. It's white in colour and it's the only thing holding the heatsink onto the BGA component.

What's weird is the spell checker. I have the word heatsink twice in the statement up above. The first one, heatsink, it says is wrong and should be heat sink. The second one, when I had it as heat sink, it says it's wrong and should be heatsink.

[diif]

Re: Using a different battery to test a Samsung N900V

Can't say i've come across a heatsink i've not been able to remove, MEK or brake cleaner are good at softening dried heatsink compound, just be careful where you get it.
A waft with a hot air wand can also soften some.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

Can't say i've come across a heatsink i've not been able to remove, MEK or brake cleaner are good at softening dried heatsink compound, just be careful where you get it.
A waft with a hot air wand can also soften some.

If it is in deed bad, I'll try the hot air. It's the only thing holding the heatsink to the BGA MT8202E processor. I tried twisting it, sometimes that helps them come off, but this one is on very good.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

This has to be some type of epoxy / thermal compound. I removed the board, I'm putting everything I have into trying to twist it off, it isn't budging a bit. I carefully took an exacto knife and tried cutting into the hard white stuff, I can't even cut it. It's like freaking cement!!!

[diif]

Re: Using a different battery to test a Samsung N900V

Use some heat 200c or some chemicals, avoid the fumes.

[Spork Schivago]

Re: Using a different battery to test a Samsung N900V

I'm not sure what MEK is. I don't have brake cleaner here, but when I was driving to my doctors today, the car handle in the car broke. We can't open the driver side door from inside the car. I gotta go to Autozone to pick up a new handle. What would give us a better chance of success? Hot air at roughly 200C or brake cleaning fluid?

There's a jumper wire that's very close to this IC that runs from the T-CON to some weird place. Not sure why it's there, but there's one on the bottom side as well. ShopJimmy has pictures of the board with the jumper wire but they're out of stock. E-bay has people selling the board, without the jumper wires. There's also a lot of caps nearby. I'm more afraid of melting that jumper wire. But I know excessive heat isn't good for caps. Should I use some of that tin foil to try and protect stuff?