PCB News - Several effective methods for pcb flying probe test

Flying probe test is one of the methods to check the electrical function of PCB (open and short circuit test). The flying tester is a system for testing PCB copy boards in a manufacturing environment.Instead of using all the traditional bed-of-nails interfaces on traditional online testing machines, flying probe testing uses four to eight independently controlled probes to move to the component under test. The unit under test (UUT,  unit under test) is transported to the testing machine through a belt or other UUT conveyor system. Then it is fixed and the probe of the tester contacts the test pad (test pad) and via hole (via) to test a single component of the unit under test (UUT). The test probe is connected to the driver (signal generator, power supply, etc.) and sensor (digital multimeter, frequency counter, etc.) through a multiplexing system to test the components on the UUT. When a component is being tested, other components on the UUT are electrically shielded by the prober to prevent reading interference. In the Massembly knowledge class, introduce professional mounting knowledge in popular text. Max Aim Technology, the country's first PCB (Max Aim Knowledge Classroom) model boarding, component procurement, and one-stop service provider!

The steps of making the flying probe test program:

Method one:

First:Import the layer file, check, arrange, align, etc., and then rename the two outer layers to fronrear. Change the name of the inner layer to ily02, ily03, ily04neg (if negative), rear, rearming.

Second:Add three layers, copy the two solder mask layers and the drilling layer to the added three layers, and change the name to fronmeng, rearming, mehole. Those with blind and buried vias can be named meta01-02,Met02-05,Met05-06 and so on.

Third:Change the two layers of copying fronng and rearming and changing the D code to the rund of 8mil. We call the frontmeneg the front test point and the rearmeneg the back test point.

Fourth:Delete the NPTH hole, find the via hole against the line, and define the untested hole.

Fifth:Use the fron and mehole as the reference layer, and change the fronmeng layer to on, and check to see if the test points are all in the open window of the front layer. The test point in the hole larger than 100mil should be moved to the welding ring for testing. The test points at the BGA that are too dense should be misaligned. Some redundant intermediate test points can be deleted appropriately. The operation of the back layer is the same.

Sixth:Copy the organized test point fronmeng to the fron layer, and copy the rearming to the rear layer.

Seventh:Activate all the layers and move to 10,10mm.

Eighth:The output gerber file is named as forn, illy02, illy03, illy04ng, illy5ng, rear, fronmeng, rearmneg, mehole, met, layer 0.12-0.9meter. Then use Ediapv software

Method two:

First:Guide all the Gerber files as forfron, illy02, illy03, illy04neg, illy5ng, rear, fronmeng, rearming, mehol, met90, 0-0, meter 10, 0-0, meter.

Second:Generate a network. net annotation of artwork button.

Third:Generate test files. Make  test   programs button, input the D code of the untested hole.

Fourth:save,

Fifth:Set the reference point, and it's done. Then take it to the flying probe machine and test it.

Personal feeling:

1.Using this method to make test files often makes many test points, and the intermediate points cannot be deleted automatically.

2.Poor grasp of the hole test. View the generated connectivity (open circuit) test points in ediapv, there is no test point for a single hole. Another example: there is a line on one side of the hole and no line on the other side. It is reasonable to test the hole on the side without a line. However, the test points generated by Ediapv conversion are random, and sometimes they are right or wrong.

3.For the REAR surface solder mask without opening window, the name of the REAR layer can be named other names, so that in EDIAPV, it will not run out of the test point inexplicably.

4.If there is only one window on both sides of the MEHOLE, but there are measuring points on both sides when you run out, you can press the make  testing programs button again. It should be noted that you can place the cursor above the MEHOLE layer.

The above is the introduction of several effective methods for PCB flying probe testing. Ipcb is also provided to PCB manufacturers and PCB manufacturing technology