element14 Community
element14 Community
    Register Log In
  • Site
  • Search
  • Log In Register
  • Community Hub
    Community Hub
    • What's New on element14
    • Feedback and Support
    • Benefits of Membership
    • Personal Blogs
    • Members Area
    • Achievement Levels
  • Learn
    Learn
    • Ask an Expert
    • eBooks
    • element14 presents
    • Learning Center
    • Tech Spotlight
    • STEM Academy
    • Webinars, Training and Events
    • Learning Groups
  • Technologies
    Technologies
    • 3D Printing
    • FPGA
    • Industrial Automation
    • Internet of Things
    • Power & Energy
    • Sensors
    • Technology Groups
  • Challenges & Projects
    Challenges & Projects
    • Design Challenges
    • element14 presents Projects
    • Project14
    • Arduino Projects
    • Raspberry Pi Projects
    • Project Groups
  • Products
    Products
    • Arduino
    • Avnet Boards Community
    • Dev Tools
    • Manufacturers
    • Multicomp Pro
    • Product Groups
    • Raspberry Pi
    • RoadTests & Reviews
  • About Us
  • Store
    Store
    • Visit Your Store
    • Choose another store...
      • Europe
      •  Austria (German)
      •  Belgium (Dutch, French)
      •  Bulgaria (Bulgarian)
      •  Czech Republic (Czech)
      •  Denmark (Danish)
      •  Estonia (Estonian)
      •  Finland (Finnish)
      •  France (French)
      •  Germany (German)
      •  Hungary (Hungarian)
      •  Ireland
      •  Israel
      •  Italy (Italian)
      •  Latvia (Latvian)
      •  
      •  Lithuania (Lithuanian)
      •  Netherlands (Dutch)
      •  Norway (Norwegian)
      •  Poland (Polish)
      •  Portugal (Portuguese)
      •  Romania (Romanian)
      •  Russia (Russian)
      •  Slovakia (Slovak)
      •  Slovenia (Slovenian)
      •  Spain (Spanish)
      •  Sweden (Swedish)
      •  Switzerland(German, French)
      •  Turkey (Turkish)
      •  United Kingdom
      • Asia Pacific
      •  Australia
      •  China
      •  Hong Kong
      •  India
      •  Korea (Korean)
      •  Malaysia
      •  New Zealand
      •  Philippines
      •  Singapore
      •  Taiwan
      •  Thailand (Thai)
      • Americas
      •  Brazil (Portuguese)
      •  Canada
      •  Mexico (Spanish)
      •  United States
      Can't find the country/region you're looking for? Visit our export site or find a local distributor.
  • Translate
  • Profile
  • Settings
Raspberry Pi
  • Products
  • More
Raspberry Pi
Raspberry Pi Forum Is my raspberry unrepairable?
  • Blog
  • Forum
  • Documents
  • Quiz
  • Events
  • Polls
  • Files
  • Members
  • Mentions
  • Sub-Groups
  • Tags
  • More
  • Cancel
  • New
Join Raspberry Pi to participate - click to join for free!
Featured Articles
Announcing Pi
Technical Specifications
Raspberry Pi FAQs
Win a Pi
Raspberry Pi Wishlist
Actions
  • Share
  • More
  • Cancel
Forum Thread Details
  • State Suggested Answer
  • Replies 64 replies
  • Answers 2 answers
  • Subscribers 674 subscribers
  • Views 8509 views
  • Users 0 members are here
  • raspberry_pi
Related

Is my raspberry unrepairable?

Former Member
Former Member over 9 years ago

First of all I'm a beginner, so please don't judge me I know I did something bad.

 

SO, yesterday I was trying to make my raspberry pi 2 B to work with an external battery. I took a lithium polymer battery with 3.7v and 2500mah and I connect it to a booster. At first I was trying to hook it up to the micro usb input on the board and it didn't work. Then I look in youtube and I saw people plugging external batteries into the gpio pins. I joined the positive cable into the the first 5v pin and the negative cord into the first 3.3v pin and vs. Although when I connected the positive cable into the first 5v pin and the negative into the 3.3v pin for the second time with longer time touching them, it sparked and then I saw it left a kind of cut in both gpio pins. Now this morning that I try to power up my raspberry with a normal micro usb cable, I can feel the board getting warm(normal warm) but the led does not turn on.

 

In the pictures attached, the voltmeter says 4.12 v output but yesterday I adjust it to 5.2v also using the voltmeter but I don't know why it shows 4.12v now... And also in the mark on gpio is the same in the other side (the first 3.3v pin).

 

Is there anything I can do? Or is it burnout forever?

 

Thanks in advance.

Attachments:
image
image
image
image
  • Sign in to reply
  • Cancel
Parents
  • Robert Peter Oakes
    0 Robert Peter Oakes over 9 years ago

    You have most lightly blown something on the PI

     

    The 4.3V battery should NOT have been connected between the 3.3V pin and the 5V pin, these are both seperate power + rails for parts of the PI board and you just put effectivly 8V into the 5V pin or caused excessive current to flow through pins not designed to have a difference of the battery or booster voltage.

     

    What you should have done is connect the batter or booster output to 0V for the black wire and 5V for the red one (Using the booster to give you the 5V

     

    you best option is actually to feed the 5V into the PI via the USB connection though, so battery to booster, booster to PI USB power connector

     

    the schamatics have not been published but based on your description of how you connected a battery capapable of providing many amps between the 3V3 and 5V pins I would expect something to have failed

     

    Sorry for the bad news, may the PI RIP.

     

    Peter

    • Cancel
    • Vote Up +1 Vote Down
    • Sign in to reply
    • Verify Answer
    • Reject Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to Robert Peter Oakes

    So I cannot replace anything (nothing has physical damage except the pins, so I thought I may be able to replace them or even replace the led xd)? And one more question how can I put the black cable to 0v (because both cable where fused with the + and - of the boost output) ?

     

    Thank for the fast responding! :O

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • dwinhold
    0 dwinhold over 9 years ago in reply to Former Member

    I have done something simular by accident, the Raspberry isn't repairable. I use mine to show people what they look like. At least I don't worry about them dropping it. Sorry about the misfortune...

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Robert Peter Oakes
    0 Robert Peter Oakes over 9 years ago in reply to Former Member

    The damage will not be visable, the pin that is marked is irrelevent, it would still work if thats all that was wrong, same for the LED

    the LED not working is symptomatic of the CPU or other significant part being damaged and with out schematics and the like, pretty imposible to repair for most folks and certainly not economically viable

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • dwinhold
    0 dwinhold over 9 years ago in reply to Robert Peter Oakes

    When plugged in does the processor get real hot?  If so, the processor is burned up from the power mixup.  Like  Peter Oakes says, fixing wouldn't be economically viable. As well, what happens when you plug in the Raspberry without An sd card?

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to dwinhold

    I just let it sit for about 15m and it's at normal warm. Also is not only the processor that gets hot, the board does too, but mostly where the micro usb port is. When I remove the micro sd card it gets hot at same temperature (maybe a little less), but again no led turn on or whatsoever.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
Reply
  • Former Member
    0 Former Member over 9 years ago in reply to dwinhold

    I just let it sit for about 15m and it's at normal warm. Also is not only the processor that gets hot, the board does too, but mostly where the micro usb port is. When I remove the micro sd card it gets hot at same temperature (maybe a little less), but again no led turn on or whatsoever.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
Children
  • shabaz
    0 shabaz over 9 years ago in reply to Former Member

    Hi Mauricio,

     

    The warmth near the microUSB is a sign that something serious is wrong, because it means either the rest of the circuit is drawing excessive current (due to blown chips) or that the DC-DC converter chip which is located near the micro-USB connector

    is faulty. Either way, the parts are tiny (about 0.4mm separation between pins, and often the pins are on the underside) and most people don't have the tools to remove and replace them (and if they do, they charge around $75USD for soldering one part - and

    no idea how much to desolder and clean up the board of the existing one).

    By wiring directly to the 40-pin connector, any (little) protection the Raspberry Pi has was bypassed. Because the supply connection was made to 5V and 3.3V rails, there is a very high risk the DC-DC converter chip has fried itself, another sign of this is the sparks you saw

    on the connector pins - it means a lot of current went through.

    In summary, the entire board has to be replaced. I didn't read the entire detail, but if your power LED is not functioning then that near-guarantees that the DC-DC converter IC (or parts near it) have died, and they are not economically replaceable.

    Not the news you want to hear, but at least by reading the comments you've learnt the technical details about what could have occurred. As a beginner, after the first board or two, you'll be fine - experience means you won't trust all instructables etc., and will take

    some precautions such as double-checking pinouts.

    • Cancel
    • Vote Up +1 Vote Down
    • Sign in to reply
    • Verify Answer
    • Reject Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to shabaz

    Thank you!

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to shabaz

    Hi,

     

    I can still use the usb, hdmi, usb ports.. etc for different projects right?

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • shabaz
    0 shabaz over 9 years ago in reply to Former Member

    Reaistically no, there is no real standard for soldered connections format, so even if they are removed, they may not fit other boards for different products.

    And they don't often go wrong they should normally outlive the life of the remainder parts on the 'pi, so won't be useful for other pi's either.

    The 40-pin connector is useful, but is very hard to remove with basic tools.

    You could perhaps use the board to practice desoldering maybe, but apart from that not much.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to Former Member

    Holy guacamole - It takes quite a bit off current to sublimate metal.  That's what Li++ batteries are made to do, however.  When you feed too much current on pins it will most likely burn out that subcircuit, as well as connected and adjacent ones.  Looking at the die for the BCM2835 (the CPU for a RPi) there are more than 40 peripherals hooked directly to power.

    The likely reason you're measuring 4.12VDC at points where you expect 5.2VDC is that when the overcurrent blew a subcircuit it created a short to ground somewhere.  That's draining off the "missing" 1.08V to ground.  The fact that the micro USB port gets so warm is that a short (maybe the "missing" power subcircuit, maybe not) is pulling a lot of current out of the power supply.  The RPi also doesn't have a voltage regulator. 

    The fact that the power LED isn't coming on is that the voltage was pushed beyond the breakdown voltage.  According to the Shockley equation, applied to diodes (you can Google it, if you're interested), a small rise in voltage can result in a large increase in current.  In plain terms: the LED is dead.  Just for information: The LED only reflects a voltage rise in the control circuit it's attached to - Board power isn't actually routed through the LED.

     

    You're unlikely to find what exactly was damaged; unless you have access to a microtome, to cut layers off the CPU and PCB, and a microscope to view features smaller than 0.1mm.  You'd likely just see where the metallic parts and adjacent PCB melted.  It would be a good learning experience, however, to use a magnifying glass or something to visually locate where the copper traces were damaged, and what accessories on the board were killed.

     

    The bottom line is that the RPi is dead.  You might be able to get some lights to come on (the network LED's, for instance) and feel hot spots where power is going through.  Even if all the peripherals were intact (highly unlikely) the "brain" of the BCM2835 is dead.  It's common with integrated boards (microcontroller, SoC, ASIC, etc.) when they get too much power to pins, to have a few things that will still work (at least for a little while).  It will never be repairable back to normal function; not would I use anything off the board in something else.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • shabaz
    0 shabaz over 9 years ago in reply to Former Member

    Hi Brian,

     

    As you say, likely the board is fried. But just as an aside (not that it matters to the end result) the LED may be intact, because it has a resistance in series. There is a DC-DC converter (well, more than one) and by connecting to +5V and +3v3 the MOSFET which is part of the buck topology inside that integrated circuit saw the supply across it with nothing to protect it : ( anyway I'm speculating any further. I could be totally wrong.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to Former Member

    So, I cannot use my boost converter since it also might be damaged? And Thank you, it's very informative!

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • shabaz
    0 shabaz over 9 years ago in reply to Former Member

    That is probably fine, but might be worth testing it before you connect it to anything. You need a multimeter to see if it gives 5V.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • Former Member
    0 Former Member over 9 years ago in reply to shabaz

    Before I joined the cables to the gpio pins, I adjusted the booster to 5.2v but after, the next day, I retest it and it showed 4.12v output.. this means it got affected?

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
  • shabaz
    0 shabaz over 9 years ago in reply to Former Member

    If its behaviour has changed then yes. Not all have protection. Anyway you have to use your own judgement and experimentation here, since I'm speculating. If you're measuring 4.2v when it was originally 5 or 5.2V then all other things being equal it looks like a fault.

    • Cancel
    • Vote Up 0 Vote Down
    • Sign in to reply
    • Verify Answer
    • Cancel
element14 Community

element14 is the first online community specifically for engineers. Connect with your peers and get expert answers to your questions.

  • Members
  • Learn
  • Technologies
  • Challenges & Projects
  • Products
  • Store
  • About Us
  • Feedback & Support
  • FAQs
  • Terms of Use
  • Privacy Policy
  • Legal and Copyright Notices
  • Sitemap
  • Cookies

An Avnet Company © 2025 Premier Farnell Limited. All Rights Reserved.

Premier Farnell Ltd, registered in England and Wales (no 00876412), registered office: Farnell House, Forge Lane, Leeds LS12 2NE.

ICP 备案号 10220084.

Follow element14

  • X
  • Facebook
  • linkedin
  • YouTube