PCB News - The difference between circuit board flying probe test and test rack test in PCB board industry

The difference between circuit board flying probe test and test rack test in PCB board industry

In the production process of PCB boards, it is inevitable that electrical defects such as short circuits, open circuits, and leakage due to external factors will inevitably be caused. In addition,PCB boards continue to evolve toward high density, fine pitch and multiple levels. If the defective boards are screened out and allowed to flow into the process, it will inevitably cause more cost waste. Therefore, in addition to the improvement of process control, the improvement of testing technology can also provide PCB board manufacturers to reduce the rejection rate and improve the product yield. s solution. The editor of the circuit board manufacturer below will let you know what is flying test and what is electrical test.

The electrical testing methods include: Dedicated, UniversalGrid, Flying Probe, E-Beam, Conductive cloth (Glue), Capacity and Brush Test (ATG-SCANMAN), of which there are three most commonly used equipment, which are dedicated tester (PCB automatic general tester), high-quality general-purpose tester and flying probe tester.

First of all, in terms of the application purpose of the testing technology, flying probe testing is currently the most suitable electrical testing equipment for small-scale production and samples. This will greatly increase the cost of testing. Regardless of the level of PCB board used for general-purpose and special-purpose types, as long as the output reaches a certain number, the test cost can reach the standard of economies of scale, and it only accounts for the price. 2~4%, which is the main reason why general-purpose and special-purpose models are currently mass-produced test models.

The flying probe tester is an improvement of the traditional needle bed on-line automatic high-voltage dedicated PCB tester. It uses probes to replace the needle bed. The XY mechanism is equipped with 4 heads that can move at a high speed and a total of 8 test probes., The minimum test gap is 0.2mm.

When working, the unit under test (UUT) is transported to the testing machine through a belt or other UUT transmission system, and then the probe of the testing machine is fixed to contact the test pad and via hole (via) to test the unit under test (UUT) Of individual components. The test probe is connected to the driver and sensor through the multiplex 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.

The flying probe tester can check short circuits, open circuits and component values. A camera was also used in the flying probe test to help find missing components. Use a camera to check the shape of components with clear orientations, such as polar capacitors.

With the probe positioning accuracy and repeatability reaching the range of 5-15 microns, the flying probe tester can accurately detect UUTs. Flying probe testing solves a large number of existing problems seen in PCB circuit board assembly: for example, a test development cycle that may be as long as 4-6 weeks; can not economically test small batch production; and can not quickly test prototype assembly.

Flying probe test is one of the methods to check the electrical function of PCB board (open and short circuit test). Flying tester is a system for testing PCB circuit 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, unitundertest) is transported to the testing machine through a belt or other UUT conveying system. Then it is fixed, and the probe of the tester contacts the test pad and the via to test the single component of the 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.

What is the difference between flying probe test and test stand? What are their respective advantages?

Flying probe test: It uses 4 probes to conduct high-voltage insulation and low-resistance continuity test (testing the open circuit and short circuit of the circuit) on the circuit board without the need for test fixtures. Directly install the PCB board and run the test program to test extremely It is convenient, saves the cost of testing, reduces the time for making test racks, improves the efficiency of shipping, and is suitable for testing small batches and prototypes.

The test rack is a special test fixture for continuity testing of mass-produced PCB boards. The production cost is higher, but the test efficiency is better, and there is no charge for returning the order.

The above is a description of the difference between flying probe testing and testing machine testing in the PCB circuit board industry. I believe you have learned a lot. If you learn a little every day, you will have a deeper understanding of circuit board manufacturers!