PCB Probe Fly Test and Electric test fixture

Flying probe and electric testing fixture are two different ways for PCB testing, and they are complementary to some extent. They have the same purpose which is to test if the PCB boards would have some problems of circuit open, short, via barriers etc. This helps to make sure the boards we dispatched to customers will be workable and perform well.

For test by fixture, it is for the solder joints that the PCB to be tested, processing a number corresponding with flexible vertical contact probe true array (also known as the needle bed). It is connected by pressure with the probe. Introduced the other end of the probe test system to complete the connection of the connected power supply, and the signal line and the measuring line. Thus completing the test. This test method is limited by the PCB pad pitch distance.

As we all know, the PCB wiring is getting higher and higher, the conduction hole diameter, the pad is getting smaller and smaller. With the increase of BGA I / O number. The diameter of test fixture test needle requires smaller and smaller. The smaller the diameter is, the more expensive it will be. Undoubtedly PCB test costs increase accordingly. In addition, the test fixture generally need to drill test template. Testing speed by fixture is faster than the fly probe test.

Proble fly test is based on the network logic of the PCB relations, 2-4-8 root can move anywhere on the PCB surface probe test. The probe is inserted in the program under the guidance and come into contact with the PCB on both ends of the DUT, the probe voltage is applied to the measuring current, in order to determine the PCB-off. Proble fly test does not require the support of the test fixture, thus eliminating the need for a special processing of the cost of the probe, as well as the cost of manufacturing test fixtures. Its test point eight probes can be moved instead of closely arranged test fixture, so it is capable of detecting very high wiring density PCB. However, moving the probe tester is based on the PCB on each network and each test point to test one by one, so it’s much slower than the test fixture test.