Category: Hardware

how to fix a dead Li-ion samsung battery

More then a year a go I put away my old Samsung phone in its box.

Totally forgotten about it I had an idea to play with it again so I tried to start it up but nothing happend.  We just need to put it in the charger again right? After a few hours charging the phone was still playing dead. Nothing nada njet niks!

Searching on the many webpages about Li-ion batteries I came to the conclusion that the best thing to do is to buy a new battery. uh huh. Now that is not going to happen.

We know that you need a bit of current in the battery for some phones to enable their in build charging circuit. But how to get it charged without a fancy charger?

If you don’t mind to let a battery explode in your face then there is a little trick.
Needless to say that you might void your warranty and you might loose some limbs doing this.. We gonna jump start it! If it works for a car why not try that for a Li-ion battery…

If you want the science behind it, why this actually works, than please search and feel free to comment 😉

This is what I did:

Strip one side of the USB cable,and tape the right poles to the battery.

USB cabble to Samsung battery

As most of the time, red goes to the + and black to the –

I used some high temperature tape that u can use for soldering. But any good tape will do.

Plugin the USB cable and keep your fingers crossed now you still got them.

After 20 minutes I pulled the plug, got rid of the the tape and inserted the battery in the phone.

Now its charging, and the phone works!

Did I tell you that this isn’t the right way to do it?
I warned you about the fact that it could blow up in your face?
I mentioned that it might void your Samsung warranty?

Yes I did! Happy hacking!

Phone is charging again

Chatting with Max from Frozen Electronics and he came up with this tip:

“Max: You could destroy the battery, the chargers have a current-limiting PNP transistor in them!

Max: In the future, there’s a pretty simple constant current circuit you can build if you’ve got a P-channel MOSFET around somewhere. the chips are a dime a dozen on Newark/digikey (even ebay) and you can control the voltage and charge speed with potentiometers. almost like a universal li-po charger.

Max: Here’s the chip, the datasheet has the circuit in it, it’s really easy to use. there’s versions of the chip for all the common li-ion voltages (4.1, 4.2, 8.2, 8.4). It’s all based around a p-channel mosfet pass transistor. http://www.ti.com/product/bq2057

Thank’s max. Might try that one next time!

Very cheap ebooks till 5 July

Some time ago I did a review about a well written linux mint book from Packt Publishing.

Because they celebrate their 10 years anniversary you can get any book from their bookshelf for only 10 dollars. So if you want that copy of the “Raspberry Pi Cookbook for Python Programmers” or some “Advanced Penetration Testing” books. You can now get them very cheap.

As they mention on their web site:

This month marks 10 years since we embarked on our mission to deliver effective learning and information services to IT professionals. To celebrate this huge milestone, we are offering ALL of our eBooks and Videos at just $10 each for 10 days – this promotion covers every title and you can stock up on as many copies as you like until July 5th.

Some of the categories you can choose the books from:

  • Application Development
  • Big Data and Business Intelligence
  • Business Skills
  • CMS and eCommerce
  • Enterprise Products and Platforms
  • Game Development
  • Instant
  • Mobile Application Development
  • Networking and Servers
  • Video
  • Virtualization and Cloud
  • Web Development

Anyway, just a few day’s left to get some of the 2000 good books for a low price.

EZ430-CHRONOS a watch that comes with a screwdriver

Texas Instrument was so kind to send the eZ430-Chronos Development Tool.

Its a watch that comes with an USB programmer and an USB access point and a screwdriver! YES no kidding! Although you can connect with it wireless you are actually encouraged to open the watch and use the usb programmer! Its on the market sinds 2010 and evolved a bit in time. I was lucky to get the latest version.

The Specs: Its has these sensors in it:

  • temperature sensor
  • battery voltage measurement
  • integrated pressure sensor
  • 3-axis accelerometer for motion sensitive control

To make it more fun it can also act as a hub for a speedometer (pedometer) and heart rate sensor.

There are loads of options you can do with it. Just see for yourself if you’re interested.

Photo from karuppuswamy.com

Photo from karuppuswamy.com

It comes with its own “Control Center” software and you can build your own software/firmware with Code Composer.

What I really like is that you can control you pc with this watch very easy. And amazing.. its can show you the time too! YES! Its like you can use your mobile to make phone calls!

 

 

FRAM MCUs for dummies

Texas Instruments and Mouser gave away this little book: “FRAM MCU’s for dummies”.

From the book cover it should teach:
Understand the technology behind Ferroelectric Random Access Memory (FRAM)
Incorporate FRAM in your embedded applications
Accelerate development time and enable truly differentiated solutions.

Its only 60 pages but I do need my spectacles to read it 😉

 

FTDI counterfeit FT232 chip?

So I was able to run the Bus Pirate with an older driver under various Windows flavours but there is still the fact that it also should work with the latest drivers.

Kamcm on the Dangerous Prototype forum digged up some links to the Arduino forum where folks were discussing the problems of a counterfeited FTDI chip. He might be right with that.

I asked Kevin from Seeed Studio if I could help them further (without having to send the “working” Bus Pirate) to China. Some Bus Pirate devices that can’t run the latest driver already arrived at the store so we checked the part numbers. One look at the the silk-screen on the FT232 chip tells us that my little BP could be a counterfeit. Seeed is investigating this chip with FTDI and has send some of the chips to a “counterfeit authenticate lab center”.

FTDI counterfeit chip on a Bus Pirate?

FTDI counterfeit chip on a Bus Pirate?

Its good to know that Seeed and Dangerous Prototype (and the people on the forum) are digging into it. Its easy to buy these parts thinking they are the real deal.

Sjaak on the DP forum explained it this way:
My guess there went something wrong in the supply chain and they bought a batch of bad (rejects) or counterfeit products. I been a couple of times into shenzhen and it is terrible hard to distinguish between genuine and fake parts (and all the variations in between). The price of the part doesnt always tell the difference. Seeed (and I think most manufacturers) have a selected trusted sources for their parts, but sometimes it slips through. 

We will wait and see. Seeed wil contact us when they know more about the chips. Time will tell. In the meanwhile I am able to use the Bus Pirate with the older driver and one piece of hardware I don’t want to work without anymore.