Re: lifetime tests of PCB markings| 27 September, 1999
| Writing the final report for my engineering studies (microsystem technology) I'm treating the identification of PCBs from automotive applications by laser marking with a data matrix code. | | | No I'm trying to set up a programme of how to test the lifetime of this mark. | | Has anyone of you experience in this field? | Is there any standard (DIN, ISO, ...) how to do? | | | Thank you for an answer. | | | Guido | Guido: The most experienced people in the field are those working at the Symbology Research Center (SRC) in Huntsville, AL, USA. This team of engineers works in conjunction with NASA to develop methods of marking the data matrix code on all types of manufactured products for traceability, error proofing, process control, etc.THey are a part of RVSI, the people who invented the code and put it in the public domain.
According to their people, the durability of the mark on PCBs depends upon the method employed to mark the board. Laser marking should last the life of the board, ink jet is dependent upon the characteristics of the ink used. (Typically, a white pad is screened on, then the mark ink jetted onto the pad.) Even if 30% of the mark is obliterated, the full set of data encoded in the mark is readable if the mark was EC200 (Reed-Solomon error correction)compliant.
Virtually all of the automotive companies are using the Data Matrix symbology in one form or another.
Some companies are actually using a removable ink, placed on the board to carry its warranty/repair history and "erased" then updated by the service depot on warranty claims.
I have included the web site for the SRC. The Director of the center is Don Roxby. If you call him, tell him I recommended that you do so. His staff hosted me for a tour recently and I was very impressed with their work!