Author Topic: Laser-ing the IC markings off on a budget.  (Read 11956 times)

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Offline Brumby

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Re: Laser-ing the IC markings off on a budget.
« Reply #50 on: March 24, 2021, 05:12:11 am »
OP: for that you nee a pulsed laser.
I wouldn't say "need" - but it is an option.

Quote
CW lasers might work, but you do induce a lot of thermal damage to the plastic, potentially degrading insulation resistance or even expose bonding wires.
The OP is well aware of this risk - it is the reason they started this thread!


As stated earlier, I'd try out various settings on chips you don't care about.  It shouldn't take long to dial in acceptable parameters.
 

Offline beanflying

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Re: Laser-ing the IC markings off on a budget.
« Reply #51 on: March 24, 2021, 06:34:16 am »
Pulsed notionally higher powered fiber lasers or CO2 (pulsed or not) won't make much difference as the power needed to ablate the surface will be a constant.

It is fairly common in Raster CO2 Laser engraving to play with the timing/switching of the pulse to get an effect or just a simple reduction in power and a change to the scan lines per X unit will drop the power and overlap of the beam.

Just checked the scan lines on the sample runs I did were 0.05mm with a typical kerf of 0.16-17 (power is not uniform across the beam either) so there is a reasonable overlap that for speeds sake alone you would cut back as well as dropping the power put into the encapsulation.
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Offline Simon

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Re: Laser-ing the IC markings off on a budget.
« Reply #52 on: March 24, 2021, 07:51:29 am »

You know, like some devices I've seen that "accidentally" have a positive DC rail on a black wire, just for grins.  ;)


https://youtu.be/CSvf6FsSnjg

You mean like the entire German automotive standard wire colour coding? Black is positive, Brown is Negative - just for kicks, luckily wost stuff is reverse polarity protected.
 
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Online coppercone2

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Re: Laser-ing the IC markings off on a budget.
« Reply #53 on: March 24, 2021, 07:53:22 am »
How I love this thread


Hopefully your bosses pay off some cancer bills for those poor kids working on the unrepairable trash
https://www.smithsonianmag.com/science-nature/burning-truth-behind-e-waste-dump-africa-180957597/

The threshold for china reverse engineering your stuff is probobly like 200 units
 

Offline Simon

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Re: Laser-ing the IC markings off on a budget.
« Reply #54 on: March 24, 2021, 07:53:31 am »
I think if you truly want potting to be a method you need to go down the routes that whoever makes banking equipment use which of course will not be cheap. Obviously people like that will be using all the other means like locking software and encryption etc.
 

Offline Simon

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Re: Laser-ing the IC markings off on a budget.
« Reply #55 on: March 24, 2021, 12:41:56 pm »
The important thing is to design for longevity and change the attitudes about constantly buying a new one. Fortunately the market i work in wants longevity and robust designs so I don't have to cut corners to the degree that commercial product cut.

i once read of a guy returning 3 lexmark printers to the store after every single one stopped working after 16 pages were printed.

I have a hard drive that mysteriously stopped working. When I went searching I discovered that this was a common fault and happened after a certain time period and that the manufacturer was offering a firmware upgrade for those that had not reached this time or if the drive had stopped working they would take it back and sort it out. I sent mine back and it was returned to me in perfect working order. No explanation was ever given of why it stopped working in correlation to a particular number of hours. We all know what happened but the manufacturer (seagate) would never admit to having a time to fail in the firmware.
 

Offline Microdoser

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Re: Laser-ing the IC markings off on a budget.
« Reply #56 on: March 24, 2021, 01:20:53 pm »
The important thing is to design for longevity and change the attitudes about constantly buying a new one.

I'm currently designing a product, and I am designing it to be easily repairable. I want the end user to keep using my product and repair it, extending the time they use my product well beyond the standard product lifetime. Every time a user needs to buy a new product is a chance they won't choose yours.

Furthermore, I will offer a repair and refurbish service at a fair price and I hope this, as well as consumable parts, will become a steady income stream. Repairs will, at the preference of the end user, be simple board switching or component level repairs to minimize repair cost. It should always be cheaper and easier to repair the product than buy a new one IMO.

I am fully aware that any vested interests will reverse engineer any product. My defence against that will be to offer superior customer service and a trustworthy brand identity.
 

Offline SilverSolder

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Re: Laser-ing the IC markings off on a budget.
« Reply #57 on: March 24, 2021, 03:31:43 pm »
The important thing is to design for longevity and change the attitudes about constantly buying a new one. Fortunately the market i work in wants longevity and robust designs so I don't have to cut corners to the degree that commercial product cut.

i once read of a guy returning 3 lexmark printers to the store after every single one stopped working after 16 pages were printed.

I have a hard drive that mysteriously stopped working. When I went searching I discovered that this was a common fault and happened after a certain time period and that the manufacturer was offering a firmware upgrade for those that had not reached this time or if the drive had stopped working they would take it back and sort it out. I sent mine back and it was returned to me in perfect working order. No explanation was ever given of why it stopped working in correlation to a particular number of hours. We all know what happened but the manufacturer (seagate) would never admit to having a time to fail in the firmware.

There are those who claim that planned obsolescence isn't a "thing".  -  It is definitely a "thing"...  in fact, every product ever (competently) designed has had a specific defined design life...   if you buy a car, everything is designed for 100K miles or 10 years...   if you buy a cell phone where the battery can't be changed, you know you are buying a product with a 2-3 year design life...   and so on.
 

Offline Alex Eisenhut

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Re: Laser-ing the IC markings off on a budget.
« Reply #58 on: March 24, 2021, 05:23:56 pm »
Hmmm, how about a CSP embedded in a cavity in the PCB? That's doable. Pot that, and I think we have some more "security". Might slow down a determined hacker by a whole extra 24 hours.
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Offline Simon

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Re: Laser-ing the IC markings off on a budget.
« Reply #59 on: March 24, 2021, 06:17:34 pm »
in fact, every product ever (competently) designed has had a specific defined design life...   if you buy a car, everything is designed for 100K miles or 10 years...

True. In Simon's case, I'm not convinced it is a blatant counter. If it was found out, Seagate would be in deep trouble.

If I were Seagate, I would have implemented a seemingly benign "performance log" or some sort of logging system that runs in the firmware NOR flash, and wait for that block to get worn out in a reliable but not exactly predictable fashion.

This is a catch me if you can thing, and I think their lawyers have done their math.

Yes I am sure you are right and I never believed that there was an explicit counter but something reasonably predictable had been implemented hence the error I guess where someone miscalculated the indirect mechanism but there was an hour count given and I think it was seagate that said there was an issue that would fail the drive after this time, but no further explanation was given
 

Offline Simon

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Re: Laser-ing the IC markings off on a budget.
« Reply #60 on: March 24, 2021, 06:33:30 pm »
A bus manufacturer engineer told me that cars are designed for 3'000 hours use. I expect it's not as direct as that and there are other factors but that is 180'000 miles at 60mph so it sounds like a reasonable figure. It is not to say the car will literally stop at 3'000 hrs but under average use you can't expect the major items to still be usable and major repairs required.

A bus he claimed lasts 50'000 hrs which with a 16 hour day is 3125 days or probably 10-15 years which is not unreasonable. The thing with life expectancy is that you have to really work hard on some systems to have that sort of durability. stuff like vibration, fine for a few hours, but over thousands of hours a wire that is not properly restrained can chafe to the point of failure.

Cars still use brushed motors because any brushed motor will likely last 3'000 hours or even if it's 1'000 hours it takes the component through the guarantee. So why use brushless motors that will outlive the car and cost 50-100% more. It makes sense to put a brushless radiator fan on a bus that lasts 40'000 hours as it will likely last the 50'000 hours or more particularly if speed controlled. Apart from the speed controllable fan saving something like £8'000 in fuel (for the price of the controller for multiple fans) the fan will never need replacing as it will last 4 times the brushed fan for an extra 50% in price...... all worth it when you will use the 40'000 hrs of the fan and for less than £100 extra you save that cost 4 times over just for the labour to replace the brushed fans. But on a car why spend £75 on a fan when a £50 fan can do the job and you are fitting 1'000'000 of them?
 

Online coppercone2

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Re: Laser-ing the IC markings off on a budget.
« Reply #61 on: March 24, 2021, 06:38:34 pm »
The important thing is to design for longevity and change the attitudes about constantly buying a new one.

I'm currently designing a product, and I am designing it to be easily repairable. I want the end user to keep using my product and repair it, extending the time they use my product well beyond the standard product lifetime. Every time a user needs to buy a new product is a chance they won't choose yours.

Furthermore, I will offer a repair and refurbish service at a fair price and I hope this, as well as consumable parts, will become a steady income stream. Repairs will, at the preference of the end user, be simple board switching or component level repairs to minimize repair cost. It should always be cheaper and easier to repair the product than buy a new one IMO.

I am fully aware that any vested interests will reverse engineer any product. My defence against that will be to offer superior customer service and a trustworthy brand identity.

And how about getting a good reputation while you are at it? People will keep buying the newer versions for many different reasons with confidence
 

Offline beanflying

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Re: Laser-ing the IC markings off on a budget.
« Reply #62 on: March 24, 2021, 06:54:56 pm »
How about keeping somewhere NEAR on the OP's topic?  :palm:
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Offline Simon

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Re: Laser-ing the IC markings off on a budget.
« Reply #63 on: March 24, 2021, 07:29:55 pm »
How about keeping somewhere NEAR on the OP's topic?  :palm:

You mean the guy who called everyone who would not give him the answer he wanted a troll and has not come back for a page and a half.
 
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Offline beanflying

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Re: Laser-ing the IC markings off on a budget.
« Reply #64 on: March 24, 2021, 07:33:31 pm »
How about keeping somewhere NEAR on the OP's topic?  :palm:

You mean the guy who called everyone who would not give him the answer he wanted a troll and has not come back for a page and a half.

Maybe because you kicked him when a nudge would have done Simon ever thought about that? You have removed and locked threads for straying off topic and YOU are leading!
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Offline KE5FX

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Re: Laser-ing the IC markings off on a budget.
« Reply #65 on: March 24, 2021, 07:50:06 pm »
How about keeping somewhere NEAR on the OP's topic? 

I think it's on topic. The OP is asking for ways to make it harder not only to copy a device, but to repair it.  Once the decision has been made to intentionally make it hard to repair a product, it's reasonable to suspect the manufacturer of intentionally limiting its service life in other ways.

My thinking has always been that no manufacturer would implement a "lifetime counter" because the risk -- meaning the product of the probability of being caught and the consequences that are likely to ensue -- would be horrific.  Then Dieselgate came along.   :palm:   So much for my thinking.

In general, though, I still believe that Hanlon's Razor applies more often than not.  Seagate's firmware problem was probably just a matter of using a 32-bit timestamp counter someplace where 64 bits would have been better.   Rest assured, they didn't make money selling drives that fail early, because people who buy lots of hard drives tend to keep track of such things. 

Likewise, the reason why cars last 100,000 miles before becoming uneconomical to own is simply because few people want to pay for new cars that last 200,000 miles before becoming uneconomical to own.  Porsche says that 70% of the cars they've ever built are still on the road... but in a world where every car has to meet that standard, billions of people are going to have to do without any cars at all.  Whether that's better or worse for humanity is definitely off topic, but the point is irrefutable.

At the end of all of this bloviation lies a simple question of engineering ethics.  If someone asks for advice on how to make their product worse, they will need to get it from someone besides me.  I buy lots of stuff myself, and I don't want it to to be more expensive, harder to repair, or for that matter, harder to understand.

You mean the guy who called everyone who would not give him the answer he wanted a troll and has not come back for a page and a half.

The funny thing is that he was actually calling me a troll.  I dislike how EEVblog gives us like 15 seconds to correct a mistake or clarify a point before appending Last edited on $DATE by $NAME, who is either trying to hide something or needed to think his half-baked post through a little further.  So I usually just delete my post when I need to edit it, and then resubmit it as a new one.  Occasionally this breaks causality.  The lesson for the OP is to use the Quote button when setting out to call people trolls, lest he troll himself.   8)
 

Offline ajb

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Re: Laser-ing the IC markings off on a budget.
« Reply #66 on: March 24, 2021, 08:15:00 pm »
Pulsed notionally higher powered fiber lasers or CO2 (pulsed or not) won't make much difference as the power needed to ablate the surface will be a constant.

It's not quite that simple.  Ablation is a thermal process, and the energy input to the top layer of material via the laser is working against the thermal conductance of the object which tends to carry away thermal power into the rest of the material.  So in order to get enough energy into the top layer of the material that you want to ablate before that energy diffuses into and thereby heats the bulk material you need to deliver that energy relatively quickly--thus a relatively high peak power is more effective.  Or more accurately, a high peak power density is required, since the ablation energy is a function of the area to be ablated.  So a cheap CW diode laser engraver could certainly cause greater heating and thermal stress or possibly chemical degradation to the part before adequately ablating the surface, both because it will have a worse beam profile and hence less effective focusing than fiber or CO2, and because it will have lower peak power versus a pulsed laser.  (And of course the wavelength is a factor too.)  Whether it's enough to make a real difference in process reliability in practice is a harder question to answer, and will depend on just how cheap and crappy of a diode laser engraver we're talking about.  Some real-world testing from which you can estimate the total energy applied to the part to get good results with either method is probably the best way to start figuring that out.
 

Offline Microdoser

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Re: Laser-ing the IC markings off on a budget.
« Reply #67 on: March 24, 2021, 08:24:19 pm »
The important thing is to design for longevity and change the attitudes about constantly buying a new one.

I'm currently designing a product, and I am designing it to be easily repairable. I want the end user to keep using my product and repair it, extending the time they use my product well beyond the standard product lifetime. Every time a user needs to buy a new product is a chance they won't choose yours.

Furthermore, I will offer a repair and refurbish service at a fair price and I hope this, as well as consumable parts, will become a steady income stream. Repairs will, at the preference of the end user, be simple board switching or component level repairs to minimize repair cost. It should always be cheaper and easier to repair the product than buy a new one IMO.

I am fully aware that any vested interests will reverse engineer any product. My defence against that will be to offer superior customer service and a trustworthy brand identity.

And how about getting a good reputation while you are at it? People will keep buying the newer versions for many different reasons with confidence

A good reputation is part and parcel of a trustworthy brand identity IMO and of course there will be newer versions which I hope previous customers will want to purchase based on their experience with the device and the company.

What I am not going to do is force them to buy a new version because they cannot repair their old version or make the repair price so high they may as well buy a new product.
 

Offline SilverSolder

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Re: Laser-ing the IC markings off on a budget.
« Reply #68 on: March 24, 2021, 08:42:05 pm »
[...] Porsche says that 70% of the cars they've ever built are still on the road... but in a world where every car has to meet that standard, billions of people are going to have to do without any cars at all.  [...]

Porsches probably get taken care of, and fixed, almost no matter what condition!  -  e.g. compared to an old Toyota taxi...
 

Offline james_s

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Re: Laser-ing the IC markings off on a budget.
« Reply #69 on: March 25, 2021, 12:02:29 am »
There are those who claim that planned obsolescence isn't a "thing".  -  It is definitely a "thing"...  in fact, every product ever (competently) designed has had a specific defined design life...   if you buy a car, everything is designed for 100K miles or 10 years...   if you buy a cell phone where the battery can't be changed, you know you are buying a product with a 2-3 year design life...   and so on.

Yes and no. In a sense it's true, but in my experience it's not a case of "we want this to fail after x number of years" but "we want this to last a minimum of x number of years, and build it as cheaply as possible." The goal is to make it cheap to build, not to make it fail, but a consequence of being cheap is that it often will not last as long.

One potential exception I can think of, back in the late 60s Westinghouse and GE each developed a formulation for the coating on mercury vapor lamp cathodes that created a translucent white deposit on the arc tube walls rather than the dark silvery black deposit of evaporated tungsten that was typical and they marketed these as their Westinghouse "Lifeguard" and GE "Bonus Line" lamps. They lasted longer, a LOT longer, I have seen some that were still going after 30 years of dusk till dawn service. After about 15 years both companies went back to the older cathode formulation and lifespan reduced to 3-5 years or so before they started getting really dim. It's possible though that even that came down to cost, and the fact that it coincides with around the everyone started pushing high pressure sodium lamps.
 
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Offline james_s

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Re: Laser-ing the IC markings off on a budget.
« Reply #70 on: March 25, 2021, 12:07:20 am »
Porsches probably get taken care of, and fixed, almost no matter what condition!  -  e.g. compared to an old Toyota taxi...

Yeah how often do you see people driving around in a 20 year old beater Porsche or Ferrari or something? I don't think I ever have. Some cars are just classics right from the start, people who buy them treat them like an investment and take good care of them. Similar is true of airplanes, go visit a small airport and look at the various Cessnas and Pipers and stuff, most people would be hard pressed to tell whether a particular plane is a 1963 model or a 2003 model, they don't restyle them every year to keep up with the fashion trends and airplanes are very expensive so people take care of them. There are also airworthiness regulations that prevent a plane from continuing to fly if it falls into disrepair. Almost any car can be made to last a long time if you take care of it. I've never owned a car with less than 100k on it, the last one I got rid of had 330k when it was totaled, the replacement currently has 267k and still going strong. Whenever anything breaks I fix it, money spent on repairs is negligible compared to what payments would be on even a cheap new car. It's all in the attitude, I don't understand the mentality of not wanting to spend more fixing a car than it's worth, most cars are not investments, you always spend more than they're worth, whether on depreciation or on repairs.
« Last Edit: March 25, 2021, 12:10:57 am by james_s »
 

Offline SilverSolder

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Re: Laser-ing the IC markings off on a budget.
« Reply #71 on: March 25, 2021, 01:38:58 am »
Porsches probably get taken care of, and fixed, almost no matter what condition!  -  e.g. compared to an old Toyota taxi...

Yeah how often do you see people driving around in a 20 year old beater Porsche or Ferrari or something? I don't think I ever have. Some cars are just classics right from the start, people who buy them treat them like an investment and take good care of them. Similar is true of airplanes, go visit a small airport and look at the various Cessnas and Pipers and stuff, most people would be hard pressed to tell whether a particular plane is a 1963 model or a 2003 model, they don't restyle them every year to keep up with the fashion trends and airplanes are very expensive so people take care of them. There are also airworthiness regulations that prevent a plane from continuing to fly if it falls into disrepair. Almost any car can be made to last a long time if you take care of it. I've never owned a car with less than 100k on it, the last one I got rid of had 330k when it was totaled, the replacement currently has 267k and still going strong. Whenever anything breaks I fix it, money spent on repairs is negligible compared to what payments would be on even a cheap new car. It's all in the attitude, I don't understand the mentality of not wanting to spend more fixing a car than it's worth, most cars are not investments, you always spend more than they're worth, whether on depreciation or on repairs.

Totally agree, my oldest car turns 30 this year (I've owned it for 20), a little Miata MX5 that has cost almost nothing to own - I treated it to new shocks, mounts, and suspension bushings all round last year, it drives like a dream.  The funny thing is how much the youngsters seem to like it - if I go to Autozone for something, I'm barely allowed to leave again, they all seem to want to talk!
 

Online coppercone2

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Re: Laser-ing the IC markings off on a budget.
« Reply #72 on: March 25, 2021, 03:14:11 am »
the problem is that some features are really good, particularly rearview camera, but it can be retrofitted.

IMO that one eventually going to save you money when you are off your game, its almost idiot proof so long you clean it in the winter
« Last Edit: March 25, 2021, 03:16:14 am by coppercone2 »
 

Offline mnementh

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Re: Laser-ing the IC markings off on a budget.
« Reply #73 on: March 28, 2021, 06:54:21 pm »
Mill the part smooth then laser-etch a in-house stock number which is "accidentally" similar to a completely unrelated part in a similar package. >:D

Some early arcade games from the pre-microprocessor era did that. I saw a board that had a standard 74xx number on a part that was obviously a bipolar PROM. Just looking at the schematic you could see it was clearly the sprite ROM.

Yebbutt by the time you have a schizz-matic you've already done 90% of the reverse-enginerding-ery, or have stolen IP which is the equivalent. ;)

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Offline mnementh

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Re: Laser-ing the IC markings off on a budget.
« Reply #74 on: March 28, 2021, 06:57:41 pm »

You know, like some devices I've seen that "accidentally" have a positive DC rail on a black wire, just for grins.  ;)


https://youtu.be/CSvf6FsSnjg

You mean like the entire German automotive standard wire colour coding? Black is positive, Brown is Negative - just for kicks, luckily wost stuff is reverse polarity protected.

Gewd laird... some people just effin' hate the color-blind, don't they...? :o

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