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Have you noticed that now more and more of our lighting is using led lighting.What is LED? Compared to the traditional light bulbs, LEDs have lower power consumption, longer lifetime and higher energy efficiency. In the PCB industry,when we say LED PCB, it refers to the pcb used for LED lighting, if you are looking for a suitable LED PCB for your lighting system, this article may bring you something. WHAT ARE LEDS COMPOSED OF?LED is an initial light-emitting diode that produces light when an electric current passes through. LEDs typically have negative and positive electrodes, which generate light in the visible light region.The LEDS are glued to the PCB by soldering process and have electrical connections for lighting.Since light-emitting diodes dissipate a lot of heat when they are in use, when you are designing LED, the metal core is usually the best choice for LED PCB, it is because that it dissipates heat more faster. Among them, the metal material aluminum is the most widely used
PCB polychlorinated biphenyls Polychlorinated biphenyls were artificially synthesized organic compounds used commercially in North America from 1929 to the late 1970s. Although Canada did not process and produce this chemical substance, it has been widely used in electrical equipment insulation, heat exchangers, water systems, and other special applications. It took decades for people to realize the global environmental pollution caused by polychlorinated biphenyls, which are mixtures of various chlorinated biphenyls and pose great harm to human health. The Canadian government once took measures to try to eliminate PCBs, but in 1977, illegal imports, processing and sales of PCBs occurred in Canada, and in 1985, PCBs were illegally released to the natural environment. The Canadian Constitution allows PCB equipment owners to continue to use PCBs until the life of the equipment. Since 1988, provincial governments in Canada have only begun to regulate the storage, transportation, and d
PCB plug terminal Part of the wire is pressed tightly and then inserted into another part, which is welded to the PCB board. The bottom mechanical principle of this connection ensures the long-term airtight connection of the product and the reliability of the finished product through this anti vibration design. Both ends of the socket can be equipped with mounting ears, which can greatly protect the connectors and prevent poor placement of the connectors. At the same time, this socket design ensures that the socket can be correctly inserted into the mother body. Sockets can also have assembly and locking buckles. The assembly buckle can be more firmly fixed to the PCB board, and the locking buckle can lock the mother body and socket after installation is completed. 1. Curved and straight pin plug terminals (incoming direction at 270, 180, and 90 degrees to PCB board) 2. Fixed with screw flange ears and flange without screws 3. Screw connection and spring connection 4. Spacing: 3
PCB insertion and extraction force detection The reason for the inspection is that there are burrs or dirt stuck at the screw teeth of a few installation holes. Especially when using the last few installation holes that have already been connected to a plug-in terminal plug socket by the factory, if the defect is found, the crimping wires of the other holes that have already been installed must be removed one by one and the plug socket replaced. In addition, due to improper matching of wire diameter and crimping aperture, or due to incorrect crimping process operation, it can also cause accidents of unstable crimping ends. For this reason, the production factory needs to conduct a test on all installation holes of the delivered plug (socket) samples before the finished product leaves the factory, that is, use loading and unloading tools to simulate the wires with crimped pins or sockets and send them in place to check whether they can be locked. According to the product technical sp
PCB self-service selection NC, is the internal product number of Nachuan Electric 1.5 refers to the cross-sectional area of the product being 1.5mm 2. Refers to the number of terminal positions, and the number of digits can be changed as a parameter ST, referring to the plug 3.50, which refers to a variable parameter with a spacing of 3.50 If: NC 1.5/2-STF-3.50 plug-in terminal blocks, only ST becomes STF, indicating a flange with side screws The terminal housing is usually labeled with product information, which allows users to identify the basic parameters of the product to prevent operational errors during installation and connection, and can play a simple preventive role. There are permanent markings on the main parts of the shell as follows: a. Terminal rated voltage (V) b. Terminal rated current (A) c. Terminal model d. Terminal trademark or manufacturer name e. Product Certification System
PCB gong board machine *Desktop single table cutting machine, with a speed of up to 100mm/s and a positioning speed of 500mm/s. *Capable of continuous cutting without interruption during loading and unloading. *A high-quality shaft system enables the system to quickly accelerate and decelerate, reduce synchronization time, improve productivity, and maintain high accuracy. *Use high-quality hardware to ensure high rigidity and performance. *All guide screws are covered to prevent dust and dirt from entering, thereby improving the lifespan and performance of the shaft. 1. Drive system motor: servo/stepper motor 2. Spindle speed: 50000r/s 3. Cutting performance: 500mm/s 4. Repetitive accuracy of driving system: ± 0.02mm 5. Cutting speed: Maximum 100mm/S depends on circuit board material and cutting quality 6. Resolution: ± 0.01mm 7. Configuration: X, Y, Z three axes, stroke: 300X300X80mm, stroke can also be customized. 8. Repetitive accuracy:<0.1mm, for the contours of stra
PCB upper shelf PCB loading rack, also known as PCB collection box, PCB automatic loading rack, SMT loading and unloading rack, etc. Widely applicable to automatic loading and unloading machines, it is acid resistant, oil resistant, high temperature resistant, non-toxic, and odorless. It can be used to hold PCB boards, making cleaning convenient, circuit board turnover convenient, stacking neatly, and easy to manage. Its reasonable design and excellent quality are suitable for transportation, distribution, storage, circulation and processing in factories. The SMT loading and unloading rack can be combined with various logistics containers and workstations, and is used in various warehouses, production sites, and other occasions. In today's world where automatic loading and unloading machines are increasingly valued by enterprises, the SMT loading and unloading rack helps complete the circulation, storage, and integrated management of PCB boards. It is a necessary product for modern
PCB upper shelf according to size 1. External dimensions: 355 * 315 * 580mm, can store 50 PCB boards. PCB board specifications: 350 * (80-250) mm PCB upper shelf Side plate guide groove. The groove depth is 3.5mm, the groove width is 8mm, and the pitch is 10mm 2. External dimensions: 355 * 320 * 563mm. Can store 50 PCB boards. PCB board specifications: 350 * (50-250) mm Side plate guide groove. The groove depth is 3.5mm, the groove width is 5mm, and the pitch is 10mm 3. External dimensions: 460 * 400 * 563mm. Can store 50 PCB boards. PCB board specifications: 460 * (100-330) mm Side plate guide groove. Groove depth 3.5mm, groove width 5mm, pitch 10mm 4. External dimensions: 535 * 460 * 570mm, can store 50 PCB boards. PCB board specifications: 535 * (50-390) mm Side plate guide groove. The groove depth is 3.5mm, the groove width is 5mm, and the pitch is 10mm.
Classified by the upstream and downstream of the industrial chain, it can be divided into raw materials - copper clad panels - printed circuit boards - electronic product applications. The relationship is simply expressed as: fiberglass cloth: fiberglass cloth is one of the raw materials of copper clad panels, made from fiberglass yarn weaving, accounting for about 40% (thick plate) and 25% (thin plate) of the cost of copper clad panels. Glass fiber yarn is made by calcining raw materials such as silica sand in a kiln into a liquid state. It is then pulled into extremely fine glass fibers through extremely small alloy nozzles, and then hundreds of glass fibers are twisted into glass fiber yarn. The construction investment of kilns is huge, usually requiring billions of funds, and once ignited, production must be uninterrupted 24 hours a day, resulting in huge exit costs. Fiberglass fabric manufacturing is similar to weaving enterprises in that it can control production capacity and q
The global PCB industry accounts for more than a quarter of the total output value of the electronic component industry, and is the industry with the largest proportion among various electronic component sub industries, with an industry scale of 40 billion US dollars. Meanwhile, due to its unique position in the electronic basic industry, it has become the most active industry in the contemporary electronic component industry. In 2003 and 2004, the global PCB output value was 34.4 billion US dollars and 40.1 billion US dollars, with year-on-year growth rates of 5.27% and 16.47%, respectively. Development status of domestic PCB industry The PCB development work in China began in 1956 and gradually expanded to form the PCB industry from 1963 to 1978. After more than 20 years of reform and opening up, due to the introduction of advanced foreign technology and equipment, single panel, double-sided board, and multi-layer board have all achieved rapid development, and the domestic PCB i
In the early years, circuit boards belonged to the high-tech industry, and most foreign companies controlled technology output, which at one time constrained and restricted the development and growth of the circuit board industry. According to Time magazine, China and India are among the most polluted countries in the world. To protect the environment, the Chinese government has been strictly formulating and implementing relevant pollution control regulations, which have affected the PCB industry. Many cities and towns are no longer allowed to expand and build new PCB factories, but the development of our circuit board enterprises is now restricted by local conditions. The more economically developed the areas, the greater the restrictions. Why? Because unconsciously, circuit board enterprises have developed into what the government sees as major polluters, energy consumers, and water users! In today's society where environmental protection and sustainable development are highly va
Frequently Asked Questions 1、 Degreasing (temperature 60-65 ℃) 1. Too much foam: abnormal quality caused by too much foam: poor degreasing effect, caused by mismatched bath solution. 2. Composition of particulate matter: The reason for the composition of particulate matter is that the filter is broken, the high-pressure water washing of the grinding machine is insufficient, and dust is brought in from the outside. 3. Finger prints cannot be degreased: Finger prints cannot be degreased due to low degreasing temperature and incorrect dispensing of medication. 2、 Micro corrosion (NPS 80-120G/L H2SO4 5% temperature 25-35 ℃) 1. The copper surface of the board is slightly white: the reason is due to insufficient grinding, oil removal, or contamination, and low concentration of liquid medicine. 2. The copper surface of the board is black: it cannot be washed clean after oil removal and is contaminated by oil removal. A pink surface on copper indicates a normal effect of micro etchi
1. Copper foil is excessively etched, and the electrolytic copper foil used in the market is generally single-sided galvanized (commonly known as ashed foil) and single-sided copper plated (commonly known as reddened foil). The common copper throwing is generally galvanized copper foil above 70um, while reddened foil and ashed foil below 18um have not undergone bulk copper throwing. 2. Local collisions occurred during the PCB process, causing the copper wire to detach from the substrate due to external mechanical forces. This defect manifests as poor positioning or directionality, where the detached copper wire will have obvious twisting or scratches/impact marks in the same direction. Peel off the defective copper wire and observe the rough surface of the copper foil. It can be seen that the color of the rough surface of the copper foil is normal, and there will be no side corrosion defects. The peeling strength of the copper foil is normal. 3. Unreasonable PCB circuit design, u
1. Engineering design: The arrangement of interlayer semi cured sheets should correspond; Multi layer core boards and semi cured sheets should use the same supplier's products; The outer C/S surface graphics area should be as close as possible, and independent grids can be used; 2. Drying board before cutting Generally, at 150 degrees Celsius for 6-10 hours, the moisture inside the board is removed, further allowing the resin to cure completely and eliminating stress inside the board; Drying the board before opening, both the inner layer and both sides are required! 3. Before laminating the multi-layer board, attention should be paid to the longitudinal and latitudinal directions of the cured sheet: The shrinkage ratio in the warp and weft directions is different, so pay attention to distinguishing the warp and weft directions before cutting and stacking the semi cured sheet; When cutting the core board, attention should also be paid to the warp and weft directions; The gener
The equipment used for curing plastic melt ink is not suitable for curing water-based ink. Except for discharge ink, other water-based inks contain chemical cross-linking agents. Only when water-based inks are sufficiently dried can they ensure the washing fastness of printed images. Some printing factories choose air drying for the solidification of water-based ink, while others make the printed matter come into direct contact with a hot platform before the ink dries, causing the moisture to evaporate, and then place the printed matter in an oven. Before coating the paper, a drying device should be used to remove moisture from the paper, which is also suitable for removing moisture from water-based inks. Perhaps the most reasonable way to remove moisture is to avoid adding water to the printing process. Therefore, if it is possible to print transparency on light or white fabrics Ink, which means using fine screen printing transparent ink, will have very little moisture.
(1) One point grounding Concentrate several grounding points of the same level unit circuit as much as possible to avoid the AC signal from other circuits from entering the same level or from the AC signal in the same level from entering other circuits. Suitable for low-frequency circuits with a working frequency of less than 1MHz. If a single point grounding is used when the working frequency is between 1-1OMHz, the length of the ground wire should not exceed 1/20 of the wavelength. In short, single point grounding is the basic principle for eliminating common impedance interference of the ground wire. (2) Multiple grounding points nearby There are a large number of common ground wires distributed at the edges of the PCB and present a semi closed circuit (anti magnetic field interference). All levels of circuits are grounded nearby to prevent the ground wires from being too long. Suitable for high-frequency circuits with signal operating frequencies greater than lOMHz. (3) Groun
Mechanical characteristics of PCB through holes When the PCB through-hole is large, our wiring space will be very small. Obviously, we want to use small PCB through-holes, but how small is appropriate? Even if the PCB plate making via is already very small and the PCB plate making via is smaller, more lines can be laid on the PCB to improve the wiring density. For products with limited product size, designers have to make the PCB through holes on the board smaller and smaller. The smaller the PCB through hole, the smaller the parasitic capacitance. This means that the smaller the PCB through hole, the better it will work in high-speed situations. In the fastest PCB design, small PCB through holes are mandatory. Of course, the cost of generating small PCB through holes is higher. In engineering design, it is inevitable that the higher the performance, the higher the cost, and PCB through holes are no exception. At present, we have three principles for PCB through holes: Small PCB th
PCB process PK: tin spraying vs gold plating vs gold deposition Gold plate and gilded plate are commonly used processes in the production of circuit boards nowadays, and many people are unable to correctly distinguish the differences between the two. Some even believe that there is no difference between the two, but in fact, they are not. Usually, when people choose gold plating, what is gold plating? When we refer to whole plate gold plating, we generally refer to "electroplated gold", "electroplated nickel gold plate", "electrolytic gold", "electroplated gold", "electroplated nickel gold plate". There is a distinction between soft gold and hard gold (usually hard gold is used for gold fingers), and the principle is to dissolve nickel and gold (commonly known as gold salt) in chemical solution, Immerse the circuit board in an electroplating cylinder and apply current to generate a nickel gold coating on the copper foil surface of the circuit board. Electroplated nickel gold is wide
The difference between PCB tin spraying and PCB tin plating The cost of PCB solder board is relatively low because it only sprays tin on the PCB on the solder pad, while tin plating includes tin on the circuit as well. PCB tin plating, as the name suggests, is the process of depositing a thin layer of tin at the PCB pad location using chemical methods, usually ranging from 10 to 30 microns. The main purpose is to prevent oxidation and better fuse SMT tin. In fact, the same purpose as gold plating and OSP requires additional tin plating during SMT. PCB tin spraying refers to the physical method of spraying a layer of tin, usually ranging from 50 to 150 microns in thickness, which is relatively thick. Do not apply tin during SMT, just melt the tin onto the component. The composition of the two types of tin must be different. PCB based tin uses a salt of tin, and the mixture is an acidic solution containing tin. But PCB tin spraying generally uses tin alloys, which are generally divide
Reasons and Preventive Measures for Poor PCB Surface Mount Welding 1、 Poor wetting Poor wetting refers to the welding process where the solder and PCB substrate welding area, after being soaked, do not generate metal to metal reactions, resulting in missed or missing solder faults. The reason for this is mostly due to the surface contamination of the welding area, or the adhesion of solder resist, or the formation of a metal compound layer on the surface of the joint, such as the presence of sulfides on the surface of silver and oxides on the surface of tin, which can cause poor wetting. In addition, when the residual aluminum, zinc, cadmium, etc. in the solder exceeds 0.005%, the wetting effect of the solder reduces the activity and can also lead to poor wetting. In wave soldering, if there is gas present on the surface of the PCB substrate, this fault is also prone to occur. Therefore, in addition to implementing appropriate welding processes, anti fouling measures should be take
The automotive electronics market is the third largest application field for PCBs after computers and communication. With the gradual evolution and development of automobiles from traditional mechanical products to intelligent, information-based, mechatronics high-tech products, electronic technology has been widely used in automobiles, and electronic products have been used without exception in engine systems, chassis systems, safety systems, information systems, vehicle Internal environment systems, etc. The automotive market has clearly become another highlight of the electronic consumer market, and the development of automotive electronics has naturally driven the development of automotive PCBs. Among the key application objects of PCB today, automotive PCBs occupy an important position. However, due to the special working environment, safety, and high current requirements of automobiles, they have high requirements for the reliability and environmental adaptability of PCBs, and
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