Deep-Sleep Problems Lead To Forensic Investigation Of Troublesome Chip

September 15, 2020 by Dan Maloney 53 Comments

When you buy a chip, how can you be sure you’re getting what you paid for? After all, it’s just a black fleck of plastic with some leads sticking out of it, and a few laser-etched markings on it that attest to what lies within. All of that’s straightforward to fake, of course, and it’s pretty easy to tell if you’ve got a defective chip once you try it out in a circuit.

But what about off-brand chips? Those chips might be functionally similar, but still off-spec in some critical way. That was the case for [Kevin Darrah] which led to his forensic analysis of potentially counterfeit MCU chips. [Kevin] noticed that one of his ATMega328 projects was consuming way too much power in deep sleep mode — about two orders of magnitude too much. The first video below shows his initial investigation and characterization of the problem, including removal of the questionable chip from the dev board it was on and putting it onto a breakout board that should draw less than a microamp in deep sleep. Showing that it drew 100 μA instead sealed the deal — something was up with the chip.

[Kevin] then sent the potentially bogus chip off to a lab for a full forensic analysis, because of course there are companies that do this for a living. The second video below shows the external inspection, which revealed nothing conclusive, followed by an X-ray analysis. That revealed enough weirdness to warrant destructive testing, which showed the sorry truth — the die in the suspect unit was vastly different from the Atmel chip’s die.

It’s hard to say that this chip is a counterfeit; after all, Atmel may have some sort of contract with another foundry to produce MCUs. But it’s clearly an issue to keep in mind when buying bargain-basement chips, especially ones that test functionally almost-sorta in-spec. Caveat emptor.

Counterfeit parts are depressingly common, and are a subject we’ve touched on many times before. If you’d like to know more, start with a guide.

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X-Ray Sleuthing Unveils The Fake In Your Adaptors

July 15, 2020 by Adil Malik 36 Comments

Lets face it, the knock-off variety of our favourite adaptors, cables and accessories are becoming increasingly challenging to spot. We would be the first to admit, to have at some point, been stooped by a carefully crafted counterfeit by failing to spot the tell-tale yet elusive indicators such as the misplaced font face, the strategically misspelled logo or perhaps the less polished than expected plastic moulding and packaging. When you finally come around to using it, if you are lucky the item is still more or less functionally adequate, otherwise by now the inferior performance (if not the initial cost!) would have made it pretty obvious that what you have is infact a counterfeit.

[Oliver] recently found himself in a similar situation, after acquiring a seemingly original Lightning to Headphone Adaptor. Rather than dismay, [Oliver] decided to channel this energy into an excellent forensic investigation to uncover just what exactly made this imitation so deceptive. He began by comparing the packaging, printed typeface and the plastic moulding, all of which gave very little away. [Oliver] concluded that atleast superficially, the clone was rather good and the only way to settle this was to bring out the X-ray, of course!

The resulting images of the innards make it blatantly obvious as to why the adaptor is indeed very fake. For a start, compared to the original adaptor, the clone hosts a far more thin BOM count! If you are really serious in getting some training to better spot counterfeits, check out a post we featured earlier on the subject!

Using A Vending Machine Bill Acceptor With Arduino

March 31, 2020 by Tom Nardi 9 Comments

We’ve all seen, and occasionally wrestled with, bill acceptors like the one [Another Maker] recently liberated from an arcade machine. But have you ever had one apart to see how it works? If not, the video after the break is an interesting peak into how this ubiquitous piece of hardware tells the difference between a real bill and a piece of paper.

But [Another Maker] goes a bit farther than just showing the internals of the device. He also went through the trouble of figuring out how to talk to it with an Arduino, which makes all sorts of money-grabbing projects possible. Even if collecting paper money isn’t your kind of thing, it’s still interesting to see how this gadget works on a hardware and software level.

As explained in the video, a set of belts are used to pull the bill past an array of IR LEDs. The hardware uses these to scan the bill and perform some dark magic to determine if it’s a genuine piece of currency. [Another Maker] notes that these readers actually need to receive occasional firmware updates to take into account new bill designs. In fact, the particular unit he has is so out of date that it won’t accept modern $5 bills; which may explain how he got it for free in the first place.

Years ago we saw one of these bill acceptors used to make a DIY Bitcoin ATM. Of course back then, a few bucks would get you a semi-reasonable amount of BTC. These days you would skip the paper currency and do it all digitally.

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Hackaday Links: November 17, 2019

November 17, 2019 by Dan Maloney 8 Comments

Friday, November 15, 2019 – PASADENA. The 2019 Hackaday Superconference is getting into high gear as I write this. Sitting in the Supplyframe HQ outside the registration desk is endlessly entertaining, as attendees pour in and get their swag bags and badges. It’s like watching a parade of luminaries from the hardware hacking world, and everyone looks like they came ready to work. The workshops are starting, the SMD soldering challenge is underway, and every nook and cranny seems to have someone hunched over the amazing Hackaday Superconference badge, trying to turn it into something even more amazing. The talks start on Saturday, and if you’re not one of the lucky hundreds here this weekend, make sure you tune into the livestream so you don’t miss any of the action.

The day when the average person is able to shoot something out of the sky with a laser is apparently here. Pablo, who lives in Argentina, has beeing keeping tabs on the mass protests going on in neighboring Chile. Huge crowds have been gathering regularly over the last few weeks to protest inequality. The crowd gathered in the capital city of Santiago on Wednesday night took issue with the sudden appearance of a police UAV overhead. In an impressive feat of cooperation, they trained 40 to 50 green laser pointers on the offending drone. The videos showing the green beams lancing through the air are quite amazing, and even more amazing is the fact that the drone was apparently downed by the lasers. Whether it was blinding the operator through the FPV camera or if the accumulated heat of dozens of lasers caused some kind of damage to the drone is hard to say, and we’d guess that the drone was not treated too kindly by the protestors when it landed in the midsts, so there’s likely not much left of the craft to do a forensic analysis, which is a pity. We will note that the protestors also trained their lasers on a police helicopter, an act that’s extremely dangerous to the human pilots which we can’t condone.

In news that should shock literally nobody, Chris Petrich reports that there’s a pretty good chance the DS18B20 temperature sensor chips you have in your parts bin are counterfeits. Almost all of the 500 sensors he purchased from two dozen vendors on eBay tested as fakes. His Github readme has an extensive list that lumps the counterfeits into four categories of fake-ness, with issues ranging from inaccurate temperature offsets to sensors without EEPROM that don’t work with parasitic power. What’s worse, a lot of the fakes test almost-sorta like authentic chips, meaning that they may work in your design, but that you’re clearly not getting what you paid for. The short story to telling real chips from the fakes is that Maxim chips have laser-etched markings, while the imposters sport printed numbers. If you need the real deal, Chris suggests sticking with reputable suppliers with validated supply chains. Caveat emptor.

A few weeks back we posted a link to the NXP Homebrew RF Design Challenge, which tasked participants to build something cool with NXP’s new LDMOS RF power transistors. The three winners of the challenge were just announced, and we’re proud to see that Razvan’s wonderfully engineered broadband RF power amp, which we recently featured, won second place. First place went to Jim Veatch for another broadband amp that can be built for $80 using an off-the-shelf CPU heatsink for thermal management. Third prize was awarded to a team lead by Weston Braun, which came up with a switch-mode RF amp for the plasma cavity for micro-thrusters for CubeSats, adorably named the Pocket Rocket. We’ve featured similar thrusters recently, and we’ll be doing a Hack Chat on the topic in December. Congratulations to the winners for their excellent designs.

Cheap Multimeter Leads Come With Extra Ohms, Free!

December 16, 2018 by Donald Papp 23 Comments

[Nop head] discovered that cheap multimeter leads costing only a few bucks can come with more than one may have bargained for. The first set had a large amount of useful-looking attachments, but the wires used for the leads were steel with a resistance of about one ohm each. With two leads in use, that means any resistance measurement gets two ohms added for free. More seriously, when measuring current, the wires can heat up rapidly. Voltage measurements would be affected the least, but the attachments and lead design expose a large amount of bare metal, which invites accidental shorts and can be a safety hazard with higher voltages.

Are all cheap multimeter leads similarly useless? Not necessarily. [nop head] also purchased the set pictured here. It has no attachments, but was a much better design and had a resistance of only 64 milliohms. Not great, but certainly serviceable and clearly a much better value than the other set.

It’s usually not possible to identify garbage before it’s purchased, but [nop head] reminds us that if you do end up with trash in hand, poor quality counterfeits can be good for a refund. That goes for electronic components, too.

What Good Are Counterfeit Parts? Believe It Or Not, Maybe A Refund

November 10, 2018 by Donald Papp 60 Comments

[Charles Ouweland] purchased some parts off Aliexpress and noticed that the Texas Instruments logo on some of his parts wasn’t the Texas Instruments logo at all, it was just some kind of abstract shape that vaguely resembled the logo. Suspicious and a little curious, he decided to take a closer look at the MCP1702 3.3v LDO regulators he ordered as well. Testing revealed that they were counterfeits with poor performance.

Left: counterfeit part. Right: genuine Microchip MCP1702-3302

Looking at the packages, there were some superficial differences in the markings of the counterfeit MCP1702 versus genuine parts from Microchip, but nothing obviously out of place. To conclusively test the devices, [Charles] referred to Microchip’s datasheet. It stated that the dropout voltage of the part should be measured by having the regulator supply the maximum rated 250 mA in short pulses to avoid any complications from the part heating up. After setting up an appropriate test circuit with a 555 timer to generate the pulses for low duty cycle activation, [Charles] discovered that the counterfeit parts did not meet Microchip specifications. While the suspect unit did output 3.3 V, the output oscillated badly after activation and the dropout voltage was 1.2 V, considerably higher than the typical dropout voltage of 525 mV for the part, and higher even than the maximum of 725 mV. His conclusion? The parts would be usable in the right conditions, but they were clearly fakes.

The usual recourse when one has received counterfeit parts is to dump them into the parts bin (or the trash) and perhaps strive to be less unlucky in the future, but [Charles] decided to submit a refund request and to his mild surprise, Aliexpress swiftly approved a refund for the substandard parts.

While a refund is appropriate, [Charles] seems to interpret the swift refund as a sort of admission of guilt on the part of the reseller. Is getting a refund for counterfeit parts a best-case outcome, evidence of wrongdoing, or simply an indication that low value refund requests get more easily approved? You be the judge of that, but if nothing else, [Charles] reminds us that fake parts may be useful for something perhaps unexpected: a refund.

Is That Part A Counterfeit? Here Are A Few Pointers

January 15, 2018 by Jenny List 59 Comments

If you order an electronic component, how do you know what it is you are receiving? It has the right package and markings, but have you got the real thing from the original manufacturer or have you got an inferior counterfeit? We hear so much about counterfeit parts, and sometimes the level of effort put in by the fraudsters is so high that from either a visual or electrical standpoint they can be hard to spot.

[Robb Hammond] writes for Aeri, with an extremely interesting guide to some of the cues for spotting a counterfeit semiconductor part. In doing so he gives us something of an insight into the techniques used by the fraudsters.

The first feature of a package to be examined are the indents. Relabeled chips often have their old markings sanded off and a coating applied to simulate the surface of an unmolested chip, and this coating can either obliterate or partially fill any indentations. Using comparison photos we are shown discernable hidden indents, and partially filled indents.

We’re shown textures and paints, and how markings can sometimes be shown as counterfeit by washing with solvent. A Cypress-marked part is found to be a cheaper Altera one under the paint, and other parts are shown with misaligned markings and markings placed over indents. Wildly varying countries of origin are claimed while seemingly retaining the same batch codes, an impossibility confirmed by manufacturers.

If you order your parts from legitimate distributors then it’s likely that what you receive will be the genuine article. However with the popularity of online auction sites and online bazaars the possibility has become ever more likely of being left with a counterfeit. Knowing some of these tips might just make the difference between the success or failure of your work, so it’s an interesting read.

Have you had any dodgy parts on your bench? Tell us about them in the comments. Meanwhile, it’s a subject we’ve covered before.

Via Hacker News.