We’ve all experienced it: that sinking feeling you get when you’ve powered up your latest circuit and nothing happens. Maybe you made a mistake in your design or you shorted something while soldering. It’s even possible that ESD damaged one of your chips. All of these issues and more are possible, maybe even inevitable, when designing your own hardware.
But what if your design is perfect and your soldering skills beyond reproach? What if your shiny new device is DOA but you’ve done everything right? A fascinating report by [Yahya Tawil] makes the case that it’s increasingly possible that you’ve run across a counterfeit component. While it’s still relatively unlikely the hobby hacker is going to get bit by the counterfeit bug, the figures and examples referenced in his report may surprise you.
[Yahya] points to a number of government studies on the rising scourge of counterfeit components, and the numbers are rather surprising. For example, the U.S Department of Commerce conducted a study between 2005 and 2008 where over 50% of respondent manufacturers and distributors had encountered counterfeit components. Another estimate claims that up to 15% of the semiconductors purchased by the Pentagon are counterfeit, presenting a serious risk to national security.
But how exactly does one counterfeit a microcontroller or transistor? Interestingly, in the vast majority of cases, old chips are pulled from recycled circuit boards and new labels are written over the original. Sometimes the forgery is as simple as changing the date code on the component or up-rating its capability (such as labeling it military spec when it isn’t), but in some cases chips with the same package will be labeled as something else entirely. Other tricks are decidedly low-tech: the documentation for the device may list functions and capabilities which it simply does not possess, artificially raising its value.
The report is a worthwhile read, even for those of us who may not be purchasing components in the same quantities as the Pentagon. It may make you think twice before you click “Buy” on that shady site with the prices that seem to good to be true.
Counterfeit components certainly seem to be on the rise from where we’re sitting. We’ve covered a number of other studies on this increasingly common trend, as well as first hand accounts ranging from successful recoveries to frustrating failures.
Some more info with plenty of photos.
http://www.aeri.com/counterfeit-electronic-component-detection/
One must assume a QC role considering the global supply chains, silicon lot errata, and seconds-bin recycling.
It got bad enough for us to only order directly form Analog Devices & TI , then physically deliver them to the assembly line.
We simply can’t trust the assembly people to source components that can’t be profiled directly (students should build an octopus if they don’t have one for their scopes yet). As even spools of resisters with the wrong tolerance, capacitors with the wrong rating/dialectic (some china MLCC also fail-closed witch can cause fires), and multi-lot pad re-printed recovered SMD parts.
It is a dangerous problem, but consumers demand cheap products.
I think it poses a greater problem these days as the rate of new hardware component families has slowed over the past 5 years.
The part that annoys me is the de-standardization of packages by some manufacturers…. I have seen some QFNs around with over 3 different oblong/trapezoidal contacts where the ground pad should be…. I can’t imagine a good re-flow without a prior glue process slowing things down a lot.
I as repairing a 3D plasma a couple of years ago and required a couple of IGBT’s. The only place I could find a supplier was an eBay store in the US.
Of course as soon as the power was applied they didn’t even go bang the set just failed to start up correctly. I eneded up sourcing a similar specked part from a manufacturer that was readily available from element 14 and low and behold the set worked
This has become a serious problem at my (unnamed) work. A trusted vendor became decidedly untrusted as they fed us a series of bogus parts. Bad capacitors in this case. Not the marked voltage rating. Sure looked correct, but X-rays demonstrated a different part inside. The worst thing is that they survived our initial burn in.
I’ve gotten what I suspect are recycled parts before, especially with ultra cheap Arduino clones. Most recently I picked up a dirt cheap pro micro (Atmel 32u4) board and it worked great at first. Then while I was working on a project with it and iterating on firmware after a few times reprogramming the chip it started to fail every now and then. Finally it just died completely and can’t be reprogrammed at all, even with an ISP.