Circuit boards according to the number of layers to be divided into single panel, double panel, and multilayer circuit boards three big classification. PCB is the English (printed circuit board) printed PCB, short for circuit board. Usually on the insulation material, according to the predetermined design, made of printed circuit, printed components or a combination of the conductive graphics known as printed circuit. The conductive pattern that provides the electrical connection between components on the insulating substrate is called the printed line. In this way, the printed circuit or printed circuit of the finished board called printed circuit board, also known as printed board or printed circuit board.
The circuit board software designed by many circuit board designers is designed according to the components of the circuit board software itself. The circuit board welding pad is not very big, so whether the circuit board welding pad is too small affects the circuit board welding?
Our common component welding methods are wave welding and tin pot welding, wave welding is through wave welding machine to circuit board welding, this welding method of circuit board welding plate is not very high requirements, the welded circuit board is more orderly, and tin pot welding of circuit board welding plate has strict requirements, many circuit board welding factory thinks that the welding plate is too big will waste tin, In fact, tin pot welding circuit board if the welding plate is too small, there will be leakage welding phenomenon, if there is leakage welding must use manual welding, that is a waste of labor, if tin pot welding circuit board welding plate is large, it is not easy to appear leakage welding phenomenon, compared to the latter although some waste of tin but the overall time and labor will save a lot, Therefore, it is recommended that the PCB designer should keep the circuit board and pad as large as possible to avoid short circuit in order to ensure high quality welding.
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Now, it is time for your company to purchase circuit boards. When your demand for circuit boards is at a loss, please be sure to keep a clear head and make a correct judgment. Because the current advertising on double-sided circuit boards, multi-layer PCB circuit boards, copper based circuit boards is countless, but the manufacturers of circuit boards are few and far between, many trading platforms let you be dazzled, and Keyou Circuit board factory is a rapid production of multi-layer circuit boards manufacturers, 13 years focus on PCB research and development and manufacturing as one of the high precision double-sided, multi-layer PCB circuit boards, the products cover LED aluminum base, Copper base circuit boards, composite bus copper substrate, foldable metal substrate, soft and hard combined board. Our company adhering to: good quality, fast delivery, to ensure that the reputation of relying on, to undertake the sample circuit board, batch, small batch pcb production.
Brief discussion on PCB short circuit test method
There are some micro short circuit, short circuit phenomenon of PCB circuit board, with ordinary low-voltage computer testing machine can not guarantee its quality, once into the hands of users will affect our own credibility. The development of high voltage computer board measuring machine to ensure the quality of PCB circuit board, ensure 100% qualified rate. Next circuit board manufacturers talk about the testing process.
Circuit board manufacturer
The low-voltage test of the double-sided circuit board was all OK, and the second test was conducted with 300V high-voltage test to test short circuit. The third time was remeasured with ordinary low pressure, and the short-circuit plate measured the second time was also determined as short circuit. The welding between two lines was counted as short circuit by measuring the short circuit point with the resistance range of multimeter, and the average resistance value was 6.7 ohms. Therefore, it should be considered as complete short circuit rather than micro short circuit. Then use a high magnifying glass to check the short circuit phenomenon can not accurately check out the short circuit point (should be the finished product has solder resistance ink).
From the double-sided circuit board test process and its resistance value can be identified as: etching side erosion produces a spike, and then the grinding process makes the spike break down to form a bridge between the wires, and then printed green oil to make the bridge is not a complete short path bridge. This double-sided circuit board test for low pressure naturally can not measure the bridge short circuit. The second high voltage is first measured as a micro short circuit, and then high voltage breakdown welding (because the copper wire is small, it does not need a lot of power to welding to form a short circuit. If the tester manufacturer can increase the allowable power of its short-circuit test current to burn the bridge contact, we will hardly see this phenomenon). So the third time the low-voltage computer test was able to detect the short circuit, and its resistance was only an average of 6.7 ohms.
The simplest and most economical and feasible method is to purchase a new grinding machine or improve the existing grinding machine, adopt the swing grinding brush and the use of ash throwing brush or low eye number of nylon brush, and then rinse with high pressure, especially the washing section has a filter device, to prevent the foreign matter that can cause short circuit from polluting the surface again. The grinding machine can remove the copper wire formed by side erosion and the protruding edge (the sticky dust machine also has a certain removal effect). Single-side circuit board at the same time the newly purchased computer testing machine should be selected high pressure machine, can reduce the circuit board micro short circuit and short circuit. This short-circuit phenomenon usually appears in the single panel, double panel and high density circuit board.