While all these complex processes are great for ensuring accurate and high-quality tests, a few other emerging advanced features make flying probe tests desirable. These include:
- Phase Difference Measurement Unit: The PDM unit sends signals to estimate the phase difference between different board sections. This feature reduces the need for isolation tests that are not necessary.
- High Voltage Stress (HVS) Test: If the PDM misses any high resistance isolation defects, the HVS test will run and apply high voltage to the various test points. Doing so will detect the flaws. 250V is the maximum application voltage in keeping with typical measurements. However, HVS provides a lot more voltage than that. It offers options ranging from 500V to 1000V, and at the same time, it ensures the use of the right amount of power to prevent damages to the boards during high resistance tests.
- Micro Shorts Detection: It is not uncommon for parts containing micro shorts to burn out due to the application of sudden high voltage. For this reason, micro shorts detection allows the application of low voltages and then increasing it gradually to prevent damages.
In a nutshell, a flying probe test carries out a comprehensive test on the board as much as it is feasible, depending on how easy it is to access a board’s design.
In simple terms, a flying test probe (FPT) is an automated system with a small number of probes that “fly” or maneuver around the top and bottom of a PCB simultaneously to contact test points. According to the instructions in a program for the specific board undergoing testing, a flying test probe moves from one test point to another according to its instructions.
FPT machines have high-precision needles that perform electrical tests to determine if a printed circuit board is in good order. An FPT test does not require custom tooling or manufacturing of a test fixture. That makes it highly cost-effective and the go-to choice for boards in the early development stage and low to mid-volume production.