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July 7, 2023 - Updated January 7, 2014 - Originally Posted Burned Chip Repair
D.D. |
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Surface mount components can be safely removed and a new component can easily be replaced using the same tools. This process is called SMT Rework and involves special tools to locally heat ALL the leads of the component at the same time to the melting point of the solder to both remove and re-solder (reflow) the component. This can be done reliably one or two times (maybe more if the operator is very careful) before the circuit board's solder pads and traces become loose or damaged. Most all contract electronic assembly manufactures have and use these tools for this purpose: to replace failed or incorrectly placed components or to provide just such a service as you are requesting. It is highly recommended that you use their expertise to do this, whether you only have one board or many boards requiring the replacement. Although you can purchase the tools they may use anywhere from several hundred to several thousand dollars, depending on the type, unless you plan to become an expert in this skill, and you have lots of boards to practice on, I would not recommend doing it yourself. Make friends with a local contract manufacture to do this. You may find that if you only have one board to fix,they will do it for little or nothing. Search the internet for contract electronic manufacture in your area and you will likely find one small enough and close by who would be willing to help you out.
Senior Project Engineer Electronic Controls Design Inc Paul been with Electronic Controls Design Inc. (ECD) in Milwaukie, Oregon for over 39 years as a Senior Project Engineer. He has seen and worked with the electronic manufacturing industry from many points of view, including: technician, engineer, manufacture, and customer. His focus has been the design and application of measurement tools used to improve manufacturing thermal processes and well as moisture sensitive component storage solutions.
From the photo my recommendation would be to spend the money on the new board sorry. Something in the system caused this thermal event and it may have damaged more than the component but inner layer to a multilayer board which is not repairable.
President/Senior Technical Consultant Foresite Mr. Munson, President and Founder of Foresite, has extensive electronics industry experience applying Ion Chromatography analytical techniques to a wide spectrum of manufacturing applications.
The big decision on this is going to be which of the options (replace or repair) is more cost effective. Yes, it is expensive to replace the board completely. Repair is certainly an option,but it will take more than a single procedure to repair the damage shown. Guidance on how to complete the repairs needed can be found in the IPC-7711/21B. There are several procedures which will need to be done since there's more than one thing wrong with the pictured assembly. You could select one of the listed procedures for each of the following steps: Component removal: procedures 3.6.1 through 3.6.6 in the 7711 Pad cleaning: procedures 4.1.1 through 4.4.1 in the 7711 Substrate repair: procedure 3.5.1 or 3.5.2 in the 7721 Trace Repair: procedures 4.2.1 through 4.2.5 if there are no internal traces or 4.2.6-4.2.7 if there are internal traces in the 7721 Component placements: procedures 5.5.1 through 5.5.6 in the 7711 The repair can be made and can leave you with a reliable connection. You need to decide whether or not you have a technician on staff who can complete the processes. If not, then you could send a technician to be certified at anyone of the IPC training centers listed on the following IPC webpage: (https://www.ipc.org/ContentPage.aspx?pageid=IPC-7711-IPC-7721#na). If you don't have a technician who you feel is able to complete the training and repair, then you may need to find a repair shop to do the work. Many of the training centers listed on the page above also do contracted repair work or should be able to point you in the right direction. As I wrote at the beginning, repair is an option. Only you can decide if repair is more cost effective than replacement.
Manager of Assembly Technology IPC Kris Roberson has experience as a machine operator, machine and engineering technician and process engineer for companies including Motorola, and US Robotics. Kris is certified as an Master Instructor in IPC-7711 / 7721, IPC A-610 and IPC J-STD 001.
That damage shown can certainly be reliably repaired and the board restored. As other experts above noted, the IPC 7711/7721 should be consulted for the proper repair procedures. Ideally, the work should be entrusted to a highly skilled, properly trained operator.
Sales Engineer Circuit Technology Center Mr. LePage has been a key member of the team at Circuit Technology Center since 1996. He has vast expertise, experience and understanding of complex circuit board rework, repair and modification operations. He is one of the most knowledgeable experts in this area across the globe.
The process would include the removal of the chip then subsequently the removal of the burnt laminate material. The procedures for these efforts are all defined in IPC 7711/7721 procedures 3.5.1/3.5.2/3.5.3. This work has been done reliably in the past. Due to the existing value added on this product the skills of the operator must be high with lots of experience. As for guidance make sure your operators have attended and been certified to IPC-7711/7721. We don't normally make recommendation in this forum, so if this information is needed please don't hesitate to contact me at your convenience.
Vice President, Technical Director EPTAC Corporation At EPTAC Corporation, Mr. Lambert oversees content of course offerings, IPC Certification programs and provides customers with expert consultation in electronics manufacturing, including RoHS/WEEE and lead free issues. Leo is also the IPC General Chairman for the Assembly/Joining Process Committee.
In general, whether you can effectively make the repair depends on:
Finally, keep in mind that if an IC has burned up, it has drawn excessive current, and there may be collateral damage;alternatively, something else may have caused the excess current, and the burned IC may be the collateral damage. The risk is that you repair the board,and it fails again, maybe immediately, maybe later. If it is going back to a customer, what will a repeat failure mean?
Process Engineer Astronautics Fritz's career in electronics manufacturing has included diverse engineering roles including PWB fabrication, thick film print & fire, SMT and wave/selective solder process engineering, and electronics materials development and marketing. Fritz's educational background is in mechanical engineering with an emphasis on materials science. Design of Experiments (DoE) techniques have been an area of independent study. Fritz has published over a dozen papers at various industry conferences.
This can be repaired. The questions I what and how much is damaged as well as what caused this and id it going to happen in the future with other assemblies? What I see is that the component has to be replaced for sure and then the traces have to be checked for internal board damage. Should be any open connections,they can be fixed by external jumpers. Schematics and Gerbers will be necessary too to understand the board layout.You can contact me to discuss more.
Engineering and Operations Management Independent Consultant Georgian Simion is an independent consultant with 20+ years in electronics manufacturing engineering and operations.
Contact me at georgiansimion@yahoo.com. Reader Comment
I am not trying to promote someone but I work for Contract EMS provider and we ship our boards for repair to Circuit Technology Center and they are good at board repair. You may have to provide a picture of the defect along with the PCB files in case if any board repair need to be performed for quote.
Sundaram, EIT LLC
There is not quite enough information, but based on the picture alone it appears as if a large blob of solder damaged the component after assembly and reflow. I cannot see any significant PWB damage, but it is hard to tell. Did the board pass any type of flying probe or functional test? Did the damage occur as a result of an electrical short when powered up, or was it in fact just a blob of solder? If this happened during power-up at test then Dr. Munson is correct, you may as well scrap the assembly because all of the other components in that particular circuit may have been subject to an electrical overvoltage condition (EOS). But if the damage is just from a blob of solder, then there is probably no need to scrap or replace the entire assembly, and simply removing the damaged component, cleaning the area, and replacing with a new component (and re-testing) should fix it.
Advanced Engineer/Scientist General Dynamics Richard D. Stadem is an advanced engineer/scientist for General Dynamics and is also a consulting engineer for other companies. He has 38 years of engineering experience having worked for Honeywell, ADC, Pemstar (now Benchmark), Analog Technologies, and General Dynamics.
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