PCB Tech - Why flying needle test for PCB proofing is important

It should be known that in the process of proofing PCB, the quality of PCB circuit board is usually checked by flying needle test.

Here, the flying needle test is an essential process in the PCB testing process. Compared to the needle bed of the test stand, the flying needle test is mainly used to test with probe and PCB circuit board. What is the difference between the accuracy and cost of the two? Below, we will find out the difference with you from Weisiyuan small edition of Shenzhen SMT Shiyan Patch Factory.

First, we introduce two probes of the flying needle tester. As the most wearable part of the machine, the probe is very easy to replace. Flying needle probes are custom probes that are flexible and easy to replace. Each probe has a life span of 1 million times, and is tested with UUTs of 1,000 test points. Without repeated testing, each probe should be pricked with 500 plates. For example, full-line flying needle machines handle 1,200 square meters per day, more than 5 material numbers and 40 million points per day. Then according to this standard, Then 40 probe heads are replaced every day. For patch processing plants with medium and high capacity, the cost of replacing needles is not much. Different needle sizes are also more flexible than needle beds. In fact, compared to the needle bed, the cost is lower, the flexibility is higher, and the specifications of each probe can be switched freely.

In terms of accuracy, the X, Y and Z axes of the flying needle tester are generally around A4, and the accuracy is (+) 30. μ M, a 200 μ M 01005 device, fully testable. The higher the general precision, the longer the development cycle, the higher the cost, and the limited application range, but even if there are some differences in the accuracy compared with the flying needle.

Application of PCB test stand:

The PCB board test stand in SMT technology workshop equipment is more suitable for enterprises with single product and high-speed production, but now the market demand is more and more diverse, and the flypin test is more applied to small and large patch processing plants. If a large patch processing plant has both high-speed product market and small batch demand, large patch processing plants have the need to use mixed production lines. However, more than 50% of China's PCB circuit board patch processing factories are small-scale patch processing factories. Flying needle testing has a wider application field than test stand testing, and is also conducive to shortening the product development cycle.

Most importantly, the size of components on PCB circuit boards is getting smaller and smaller, the test points and solder points on PCB board are getting smaller and smaller, and the minimum spacing between pins on PCB test stand needle bed is also 1mm, which cannot be tested μ M-level spacing, in which case the average flying needle can achieve 100 μ M test. In terms of accuracy, the flying needle test used by SMT technology shop equipment in PCB Factory has more obvious advantages, but the only disadvantage is that the production efficiency is very slow.