How to identify a chip which has its ID wiped off it
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Specmaster
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How to identify a chip which has its ID wiped off it
I'm working on a night light that has one chip that has had all of its identity wiped off it, and even under a microscope I can see no trace of what it was. I seem to remember that there is a method to make any residue marking become more visible, but I'm struggling to find any links on the internet of how to do it, anyone got any ideas
Who let Murphy in?
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Re: How to identify a chip which has its ID wiped off it
If they've deliberately attempted to remove the chip's identity, they will have used a laser or abrasive to remove the top layer of casing. This is done with various items of Chinese equipment. I can't seen any possible way of making it readable, because there's nothing to make readable.
If the markings have become indistinct through handling, you may have a chance of reading it. I find a jeweller's eye glass, and holding it at the right angle for the light to catch it, often works. There may be other ways to make it more readable. Google is your friend for things like this. You might also search Youtube, which sometimes succeeds when Google doesn't. There may be something along the lines of an ingenious use of superglue.
With valves what sometimes works, is to breathe on the marking then quickly look at the valve in glancing light, and before the condensation evaporates, you may catch a ghostly image of the markings. Sometimes it works. I haven't tried it with ICs. If I did, I think five minutes in the deep freeze would help.
Other than that, if it's for a night light, I can't imagine the circuit would be very complicated, so trace it out and work out what the chip is doing, then you can probably find a substitute. It might be a micro controller, in which case you have to work out what it is doing and program a suitable replacement - OK if you are geared up for that, but a lot of hassle if you are not.
A photo of the chip in the circuit would make it easier to make helpful suggestions as to what it is.
If the markings have become indistinct through handling, you may have a chance of reading it. I find a jeweller's eye glass, and holding it at the right angle for the light to catch it, often works. There may be other ways to make it more readable. Google is your friend for things like this. You might also search Youtube, which sometimes succeeds when Google doesn't. There may be something along the lines of an ingenious use of superglue.
With valves what sometimes works, is to breathe on the marking then quickly look at the valve in glancing light, and before the condensation evaporates, you may catch a ghostly image of the markings. Sometimes it works. I haven't tried it with ICs. If I did, I think five minutes in the deep freeze would help.
Other than that, if it's for a night light, I can't imagine the circuit would be very complicated, so trace it out and work out what the chip is doing, then you can probably find a substitute. It might be a micro controller, in which case you have to work out what it is doing and program a suitable replacement - OK if you are geared up for that, but a lot of hassle if you are not.
A photo of the chip in the circuit would make it easier to make helpful suggestions as to what it is.
Re: How to identify a chip which has its ID wiped off it
Looking on Youtube, there are a couple of ways to make lasered chip markings more visible. One is to use a piece of Sellotape.
https://www.youtube.com/watch?v=OesIvcG ... nnel=w2aew
another is to rub a small amount of heatsink compound across the chip and wipe it off.
https://www.youtube.com/watch?v=C5Ww4zq ... nAudioTech
Both are easy enough to try, but neither are of any use if the chip markings have been obliterated deliberately.
https://www.youtube.com/watch?v=OesIvcG ... nnel=w2aew
another is to rub a small amount of heatsink compound across the chip and wipe it off.
https://www.youtube.com/watch?v=C5Ww4zq ... nAudioTech
Both are easy enough to try, but neither are of any use if the chip markings have been obliterated deliberately.