Sanded chips - Page 1
Forum section: electronics / beginners

author: Austinthemighty
author_rank: Newbie
timestamp: November 01, 2017, 04:23:13 pm
content: Why do some manufactures sand the top of there chipsfor example, if you look at this board all three of the chips have been sanded

author: fourtytwo42
author_rank: Super Contributor
timestamp: November 01, 2017, 04:30:52 pm
content: This has been going on for donkeys years, its just one way of obscuring the design, making it more difficult for others to copy, I used to do it to power transistors in my amplifiers before time began

author: timb
author_rank: Super Contributor
timestamp: November 01, 2017, 04:31:54 pm
content: It’s a lame attempt at preventing you from reverse engineering the design. It rarely works out, however, as a skilled engineer can generally figure out what the chip is anyway simply by function, package and tracing the connections. Failing that you can always dissolve the chip package and look at the die itself, which will sometimes contain identifiers.

author: CM800
author_rank: Frequent Contributor
timestamp: November 01, 2017, 04:32:23 pm
content: It's very common on stepper drives and controllers from Asia, Leadshine expecially.often they do a half arsed job of it, if you rub some thermal paste into it, you can read most of it sometimes.

author: Bud
author_rank: Super Contributor
timestamp: November 01, 2017, 04:49:36 pm
content: Because there is a big nation of thieves living somewhere in Asia. They steal from the West and then steal from each other. They sand chips trying to prevent their brothers to steal from them.

author: CM800
author_rank: Frequent Contributor
timestamp: November 01, 2017, 04:59:10 pm
content: Quote from: Bud on November 01, 2017, 04:49:36 pmIt's open source hardware, but you have to work for it.

author: Mr. Scram
author_rank: Super Contributor
timestamp: November 01, 2017, 11:28:54 pm
content: Quote from: timb on November 01, 2017, 04:31:54 pmThe problem with the method is that you will catch out amateurs, but will hardly slow down organised copycats.

author: technogeeky
author_rank: Frequent Contributor
timestamp: November 01, 2017, 11:41:26 pm
content: I want to point out that it's also a hint that the volumes on the assembled device are relatively low. If they were high, the manufacturer could easily ask for parts with their own label and/or part number on the ICs (probably for free or almost for free). In this way, they could hide the part identification for the device without looking amateurishandwithout paying for the cost of someone to drill/sand it off, or the time required to put the device or IC in a jig to laser etch it off.So it's only used for relatively low production volumes, and it only defeats relatively low skilled or low effort reverse engineering attempts. Low skilled because it's not difficult at all to take a completely populated board with labeled ICs, depopulate the board, and completely reverse the thing. I could do this, and I'm barely beyond monkey level intelligence. Low effort because, many ICs are labelled with identifying information on-die, so a hot plate, some fuming nitric acid, and a decent microscope are all that are needed to overcome this.

author: Zero999
author_rank: Super Contributor
timestamp: November 02, 2017, 12:06:05 pm
content: Quote from: fourtytwo42 on November 01, 2017, 04:30:52 pmOh dear, that was lame. Only a couple of seconds with a transistor tester will identify them. A 5 year old could do it.