Ask the Experts
July 10, 2018
Burned Chip Repair
I have a circuit board with a burned chip. The manufacturer wants to charge an arm and a leg for a new board. Can this type or repair be done reliably? Where can I turn for guidance? Do you know anyone I can send this board to and have it done professionally?
Expert Panel Responses
Surface mount components can be safely removed and a newcomponent can easily be replaced using the same tools. This process is calledSMT Rework and involves special tools to locally heat ALL the leads of thecomponent at the same time to the melting point of the solder to both removeand re-solder (reflow) the component. This can be done reliably one or twotimes (maybe more if the operator is very careful) before the circuit board'ssolder pads and traces become loose or damaged.
Most all contract electronic assembly manufactures have and usethese tools for this purpose: to replace failed or incorrectly placedcomponents or to provide just such a service as you are requesting. It ishighly recommended that you use their expertise to do this, whether you onlyhave one board or many boards requiring the replacement.
Although you can purchase the tools they may use anywhere from severalhundred to several thousand dollars, depending on the type, unless you plan tobecome an expert in this skill, and you have lots of boards to practice on, Iwould not recommend doing it yourself. Make friends with a local contractmanufacture 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 contractelectronic manufacture in your area and you will likely find one small enoughand 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.
Fromthe photo my recommendation would be to spend the money on the new boardsorry. Something in the system caused this thermal event and it may havedamaged more than the component but innerlayer to a multilayer board which isnot repairable.
President/Senior Technical Consultant
Mr. Munson, President and Founder of Foresite, has extensive electronics industry experience applying Ion Chromatography analytical techniques to a wide spectrum of manufacturing applications.
Thebig decision on this is going to be which of the options (replace or repair) ismore 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.
Guidanceon how to complete the repairs needed can be found in the IPC-7711/21B. Thereare several procedures which will need to be done since there's more than onething wrong with the pictured assembly.
Youcould select one of the listed procedures for each of the following steps:Componentremoval : procedures 3.6.1 through 3.6.6 in the 7711
Padcleaning: procedures 4.1.1 through 4.4.1 in the 7711
Substraterepair: procedure 3.5.1 or 3.5.2 in the 7721
TraceRepair: procedures 4.2.1 through 4.2.5 if there are no internal traces or4.2.6-4.2.7 if there are internal traces in the 7721
Componentplacements: procedures 5.5.1 through 5.5.6 in the 7711
Therepair can be made and can leave you with a reliable connection.
Youneed to decide whether or not you have a technician on staff who can completethe 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:
Ifyou don't have a technician who you feel is able to complete the training andrepair, then you may need to find a repair shop to do the work. Many of thetraining centers listed on the page above also do contracted repair work orshould be able to point you in the right direction.
As I wrote at the beginning, repair is an option. Only you can decide ifrepair is more cost effective than replacement.
Manager of Assembly Technology
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.
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 thensubsequently the removal of the burnt laminate material. The procedures forthese 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 theexisting value added on this product the skills of the operator must be highwith lots of experience.
As for guidance make sure your operators have attended and been certified to IPC-7711/7721.
We don't normallymake recommendation in this forum, so if this information is needed pleasedon't hesitate to contact me at your convenience.
Vice President, Technical Director
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.
Ingeneral, whether you can effectively make the repair depends on:
Finding a replacement part is usually not difficult unless the part iscustom, very old, or very uncommon. Removal of the old part and cleaning of thesite can tell you if the board is repairable. Look at IPC 7711 and 7721 forguidance on what's acceptable.
Finally, keep in mind that if an IC has burnedup, it has drawn excessive current, and there may be collateral damage;alternatively, something else may have caused the excess current, and theburned 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 acustomer, what will a repeat failure mean?
- Gaining access to thereplacement part,
- Determining that thePWB has not been damaged beyond repair
- Determining that therisk of using the repaired board is reasonable, and that you are legallyallowed to do it
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 isdamaged as well as what caused this and id it going to happen in the futurewith other assemblies?
WhatI see is that the component has to be replaced for sure and then the traceshave to be checked for internal board damage. Should be any open connections,they can be fixed by external jumpers.
Schematicsand Gerbers will be necessary too to understand the board layout.You can contact me to discuss more.
Engineering and Operations Management
Georgian Simion is an independent consultant with 20+ years in electronics manufacturing engineering and operations.
Contact me at firstname.lastname@example.org.
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