ScanWorks® delivers test coverage ICT can’t

A motherboard with five daughtercards just wasn’t getting the test coverage that the manufacturer wanted from its in-circuit test (ICT) systems. As a result, Testing House Mexico, a member of ASSET®’s network of Partner Providers, was called in and eventually deployed a boundary scan test solution integrated into the manufacturer’s ICT systems. The solution involved the ScanWorks platform for embedded instruments integrated with Agilent Medalist 3070 ICT systems.

“The ICT systems weren’t able to treat the entire assembly of one main motherboard and five daughtercards as one unit under test (UUT),” said Juan Jose Montes, senior test engineer for Testing House. “And there were sections of the motherboard and daughtercards where there was no way to get probe access for ICT test. We had to come up with a boundary-scan test solution and that’s where ScanWorks integrated into the Agilent 3070 was able to deliver the test coverage we couldn’t get otherwise.”

The assembly was developed by Nokia Mountain View division, which was subsequently sold to Checkpoint Software Technologies Ltd. High-volume manufacturing of this design is still ongoing in Asia.

“Testing House looked at our design and came up with the highest test coverage solution at the lowest cost,” said Michael Nebeker, test engineer for the Nokia Mountain View division. “We wanted to run some of our boundary scan tests on the benchtop too, which is where ScanWorks came in.”

Testing House developed a pneumatic stub for the ICT fixture which allowed the entire assembly to be tested as one UUT. ScanWorks integrated on the 3070 was then employed to test interconnects on the motherboard and five daughtercards, as well as the connectors between the daughtercards and motherboard.

“We had to deal with the absence of access for ICT probes and there was no way to test the connectors,” Montes explained. “Sometimes test coverage from ICT is low and boundary-scan test is a good way to make up for low coverage.”

Testing House was able to take advantage of the integrated ScanWorks solution for the Agilent 3070 ICT systems. Boundary-scan tests were developed on ScanWorks and then ported over to the 3070 where the ScanWorks boundary-scan tests were integrated into the assembly’s manufacturing test suite.

“Developing tests on ScanWorks was accomplished very quickly, in less than a week,” Montes said. “And then when we integrated the tests into the ICT systems, it was very smooth. It probably took less than a couple of days to integrate the tests into the ICT systems. Compared with the ICT portion of the project, the ScanWorks test development and integration into ICT went very smoothly.”