EEVblog Electronics Community Forum
Electronics => Manufacturing & Assembly => Topic started by: mrpackethead on October 18, 2018, 10:06:33 pm
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Been discussing this today, wonder what its like.
http://www.x-image.com.cn/product.html (http://www.x-image.com.cn/product.html)
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I'm in Shenzhen, but I have never heard of anyone use their x-ray, maybe you should better ask more details about the safety and their customer in the past.
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For noncommercial use I'd just look for a Faxitron cabinet. It will be much cheaper. The Faxitron only does 35 kVp versus 50 kVp, but it's rare that 35 isn't enough for basic reverse-engineering tasks and inspection of PCBs with less than a dozen layers.
The Chinese machine would come with manufacturer support, of course. Presumably.
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There's a WORKING MX20 on eBay USA for $699+$450 shipping. If someone needs it, grab it now.
Be sure to ask them about the PC that goes with it, though, if you don't want to build your own frame grabber.
Edit: if it's this one (https://www.ebay.com/itm/Faxitron-MX-20-Radiography-System/232934374308), it's an old film-based model, not digital. The price is certainly attractive but it'll take a lot of work to get good imagery out of it.
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For noncommercial use I'd just look for a Faxitron cabinet. It will be much cheaper. The Faxitron only does 35 kVp versus 50 kVp, but it's rare that 35 isn't enough for basic reverse-engineering tasks and inspection of PCBs with less than a dozen layers.
The Chinese machine would come with manufacturer support, of course. Presumably.
35kVp is very limiting - it's ok on some PCBs with a few, thin layers but if you're buying something specifically for PCB work you definitely need more as there will be many boards for which 35kVp is pretty useless.
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35kVp is very limiting - it's ok on some PCBs with a few, thin layers but if you're buying something specifically for PCB work you definitely need more as there will be many boards for which 35kVp is pretty useless.
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Not in my (extensive) experience. I'd give up a kidney before giving up my MX20. :) Of course, I don't design PC motherboards with 20+ layers or anything like that.
I have never seen a PCB with 8 layers or less that I couldn't image successfully at 35 kVp with a long-enough exposure. Where it does fall short, though, is when attempting to look through any but the lightest shielding. More voltage would help there, certainly.
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I don't use my MX20 much, but have often been disappointed at what's visible on the max 35kv,19 sec settings
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I don't use my MX20 much, but have often been disappointed at what's visible on the max 35kv,19 sec settings
Yours has the Hamamatsu sensor, correct? Those are supposed to be better than the Bioptics panels, although I've never had any complaints with mine. I've occasionally had to run 30+ second exposures, but the sweet spot is usually more like 15-18.
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I verifyed with the guys making this, it is a 75kVe unit. I'm certainly not interestd in using film. That is going to be way too slow of a process.
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For noncommercial use I'd just look for a Faxitron cabinet. It will be much cheaper. The Faxitron only does 35 kVp versus 50 kVp, but it's rare that 35 isn't enough for basic reverse-engineering tasks and inspection of PCBs with less than a dozen layers.
The Chinese machine would come with manufacturer support, of course. Presumably.
This is for small commerical use.
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If it's commercial, what value do you expect to get from having one?
How is the $7k going to pay itself back?
Plenty of full time assembly places have them, and they're great for running first articles of a batch through to test process suitability, but for non fulltime production, and a limited number of in house products you can really get into optimisation for over multiple batches, how much value does this imaging have?
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If it's commercial, what value do you expect to get from having one?
How is the $7k going to pay itself back?
Plenty of full time assembly places have them, and they're great for running first articles of a batch through to test process suitability, but for non fulltime production, and a limited number of in house products you can really get into optimisation for over multiple batches, how much value does this imaging have?
Removing the uncertainty out of a prototype that is using BGA's etc were you can't see the pins.. Once you have a working prototype, you can be confident the design works. When its untested, theres lots of areas.. Is the board designed ok, was it soldered properly..
We also manufacture our own products in house, so being able to check the the setup / tune the processs's is really helpful. I agree, using this to check every product would be unworkable.
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I don't think you can get enough claer x-ray photo if it's less than 50KV, you will need a a x-ray machine with 60KV+, 90KV will be better.
the photo below is my phone under 90KV
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Removing the uncertainty out of a prototype that is using BGA's etc were you can't see the pins.. Once you have a working prototype, you can be confident the design works. When its untested, theres lots of areas.. Is the board designed ok, was it soldered properly..
I think you're a bit too paranoid about BGAs. BGA reflow technology is much better than you think, and in many cases you can isolate the problem quite easily without x-ray.
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Removing the uncertainty out of a prototype that is using BGA's etc were you can't see the pins.. Once you have a working prototype, you can be confident the design works. When its untested, theres lots of areas.. Is the board designed ok, was it soldered properly..
I think you're a bit too paranoid about BGAs. BGA reflow technology is much better than you think, and in many cases you can isolate the problem quite easily without x-ray.
Yeah nah, imagine if the BGA you are using is high density and/or fine pitch. How are you going to verify that a ball in the centre of the package has soldered down properly (good fillet with pad, minimal voids...)
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Yeah nah, imagine if the BGA you are using is high density and/or fine pitch. How are you going to verify that a ball in the centre of the package has soldered down properly (good fillet with pad, minimal voids...)
It's easy - even a single uncollapsed ball will not let the device "drop" during reflow (anyone familiar with BGA will know what I'm talking about) so you can easily see if there is a soldering failure. But if you follow manufacturer's recommendations regarding stencil thickness (important for very fine-pitch BGAs, <0.5 mm) and reflow profile, the chances of failure are extremely low. Unless your devices are going to be used in some super-critical systems like life support, it will take an eternity for X-ray machine to pay for itself. Just look up (or ask your assembly house if you have one) the failure rate of BGA soldering and you will see that it's very low.
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Yeah nah, imagine if the BGA you are using is high density and/or fine pitch. How are you going to verify that a ball in the centre of the package has soldered down properly (good fillet with pad, minimal voids...)
It's easy - even a single uncollapsed ball will not let the device "drop" during reflow (anyone familiar with BGA will know what I'm talking about) so you can easily see if there is a soldering failure. But if you follow manufacturer's recommendations regarding stencil thickness (important for very fine-pitch BGAs, <0.5 mm) and reflow profile, the chances of failure are extremely low. Unless your devices are going to be used in some super-critical systems like life support, it will take an eternity for X-ray machine to pay for itself. Just look up (or ask your assembly house if you have one) the failure rate of BGA soldering and you will see that it's very low.
would only need to eliminate the uncertaintiy from two or theree situationas and it woudl pay for it self.
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Yeah nah, imagine if the BGA you are using is high density and/or fine pitch. How are you going to verify that a ball in the centre of the package has soldered down properly (good fillet with pad, minimal voids...)
It's easy - even a single uncollapsed ball will not let the device "drop" during reflow (anyone familiar with BGA will know what I'm talking about) so you can easily see if there is a soldering failure. But if you follow manufacturer's recommendations regarding stencil thickness (important for very fine-pitch BGAs, <0.5 mm) and reflow profile, the chances of failure are extremely low. Unless your devices are going to be used in some super-critical systems like life support, it will take an eternity for X-ray machine to pay for itself. Just look up (or ask your assembly house if you have one) the failure rate of BGA soldering and you will see that it's very low.
would only need to eliminate the uncertaintiy from two or theree situationas and it woudl pay for it self.
How about JTAG boundary scan to check if BGA pins connected?
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Connected can be so variable. A whisker thin join would pass a boundary scan and fail a few months later.
I'm quietly hoping someone buys one of these cheap x-rays and posts some honest feedback.
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Connected can be so variable. A whisker thin join would pass a boundary scan and fail a few months later.
I'm quietly hoping someone buys one of these cheap x-rays and posts some honest feedback.
The full-scale images on their example page (http://www.x-image.com.cn/images.html) look great. The best ones are somewhat better than what I can get out of the Faxitron.
Just to show what is achievable at lower voltages, this message (https://www.eevblog.com/forum/projects/the-x-ray-image-thread-by-aurora-various-electronics-via-x-ray-imaging/msg1174830/#msg1174830) has some photos of a BeagleBone Black PCB taken with my 35 kVp (uh, well, OK, 37 kVp) MX-20. Lots of other good examples from Fraser and other people in that thread. As you can see, sub-50 kVp voltages are useful for basic PCB inspection as long as you have a microfocus tube paired with a good sensor. If you don't have those things, more voltage won't help.
This is a 6-layer board, and I have had good results with 8 layers of 1-oz copper as well. 10+ layers is probably pushing it. You may not be able to shoot through a whole cell phone, but that is debatably useful in a board-level inspection context.
If you are only interested in BGA inspection, an X-ray machine isn't really the best tool for that job. It is much better than nothing, but what you really want is an optical fiber scope similar to this one (https://www.kurtzersa.com/electronics-production-equipment/rework-inspection-systems/inspection-systems/produkt-details/ersascope-1.html). If you are lucky enough to be equipped with both X-ray and fiber, there's not much you can't inspect.
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How dpoes that scope see pins that are past the first row?
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How dpoes that scope see pins that are past the first row?
It doesn't. BTW the prism adapter for the handheld model is nearly Eu5000 ....
https://www.ersa-shop.com/inspektionssysteme-ersa-mobile-scope-c-47_53.html (https://www.ersa-shop.com/inspektionssysteme-ersa-mobile-scope-c-47_53.html)
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How dpoes that scope see pins that are past the first row?
That may not actually be the model I'm thinking of. A guy whose shop I visited once has an actual fiber endoscope that will look past the first row. It has to be illuminated by a 'spray' of dozens of other fibers (for want of a better term) that can be worked underneath the BGA package.
I didn't get a chance to play with it in person, but I watched his tech use it, and I noticed that it was harder to control the illumination than it was to direct the camera. The images he was getting were nothing short of amazing, but I don't think it could visualize every ball. It might not have worked past the first couple of rows, or it might have only been useful on 0.8 mm and larger parts. But the tech pointed out that the first couple of rows is usually enough to tell if your process has a problem.
Edit: it may have been one of these Optilia systems (http://www.optiliaindustrial.eu/umbraco/WebshopOptilia/cache/ProductFiles/321/2%20-%20Brochure,%20BGA%20Inspection%20Systems.pdf) (1.5 MB .PDF). The idea behind the fiber light bundle is to hit the balls being inspected from as many angles as possible. The camera probes themselves are still too thick to fit beneath most packages (0.8 mm) but that doesn't seem to be all that important.
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If you're doing small volume, a used dental head and some mammography or industrial film and surplus cassettes can all be had for a few hundred bucks. With some practice you can image the bonding wires in tiny SMT packages.