Improving Flying Probe Test Coverage Using D-Scan and C-Scan
For one of our Sprint Flying Probe test development projects, our customer had initially requested that a test program be developed only for testing the analog devices on their board. The reason for this was to minimize test program development cost. So, ICs and connectors sections were not being tested. As such, a non-functioning board could be the result of a defective IC or connector but, our customer would not be aware of this. Once the test program was used in production, a large percentage of boards were identified as failing. After troubleshooting these boards, it was determined that the primary cause was a defective IC. Consequently, our customer decided to increase the test coverage on their boards by having the ICs and connectors tested. To achieve this, the D-Scan and C-Scan Vectorless test option on the Sprint Flying Probe was used. D-Scan and C-Scan Vectorless Test Tool Set This tool set extends fault coverage to any IC, including BGAs and ICs with heat sinks, as well as connectors and polarized capacitors. D-Scan, which is available on any combination of Flying and Fixed probes, uses protection (parasitic) diodes built into many devices to test failing pins. One stationary probe is required per power supply node. C-Scan is available on all four Flying heads and uses a capacitive coupling technique to check for open pins on ICs with no protection diodes. It can be used to check for opens on connectors and orientation of polarized capacitors. Each C-Scan probe assembly includes one retractable capacitive sensor.