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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
1： The distance from the edge of the circuit board is generally not less than 2MM. The shape of the circuit board is rectangular, and the aspect ratio is 3:2 or 4:3. When the surface size of the circuit board is greater than 200MM by 150MM, the mechanical strength that the circuit board can withstand should be considered. 2： In general, all components should be arranged on the same side of the circuit board. Only when the top layer components are too dense can some highly limited and low heat generating devices, such as SMD resistors, capacitors, ICs, etc., be placed on the lower layer. 3： The minimum spacing between adjacent solder pads of different components on the PCB sample circuit board should be at least 1MM. 4： On the premise of ensuring electrical performance, components should be placed on a grid and arranged parallel or perpendicular to each other, in order to be neat and beautiful. In general, components are not allowed to overlap; The arrangement of components shoul
Counting the busy people in 2012, there are indeed many. Du Fu is busy getting graffiti, Mr. Bao is busy clarifying his skin color, and Yuan Fang is busy answering questions and solving doubts. However, the busiest thing to say is the consumers who choose from countless electronic products. The electronics industry is fiercely competitive, and consumers are undoubtedly the biggest beneficiaries. Under the competition of electronic products, the electronic component industry has attracted much attention. When PCB copying breaks the traditional circuit board industry and embarks on a "non mainstream" path, colorful and exciting scenes will surely unfold one after another. Circuit boards are important electronic components and support electronic components. Circuit board copying (PCB copying) is a reverse research technique that can visualize the core technology of electronic products and absorb it into one's own technology. As a leading enterprise in the board copying industry, Xing
1. Function and Characteristics: Nickel plating is used as a substrate coating for precious and base metals on printed circuit boards (PCB), and is also commonly used as a surface layer for certain single-sided printed boards. The PCB sampling manufacturer tells you that for heavy load worn surfaces such as switch contacts, contact pads, or plug gold, using nickel as the gold substrate coating can greatly improve wear resistance. When used as a barrier layer, nickel can effectively prevent the diffusion between copper and other metals. The combination coating of matte nickel/gold is often used as a metal coating for corrosion resistance, and can meet the requirements of hot pressing welding and brazing. Only nickel can be used as a corrosion resistant coating with ammonia based etchants, and PCBs that do not require hot pressing welding and require a bright coating are usually coated with smooth nickel/gold. The thickness of nickel coating is generally not less than 2.5 microns, us
1. During the production process, loose materials may be generated due to equipment and other factors. Therefore, during the operation process, the operator should check the material step distance before pasting and when taking over the shift. Each time the garbage is poured, the throwing box and garbage bin should be checked to collect the loose materials. At the same time, excessive abnormal situations of loose materials should be reported to the line leader. 2. Classify the bulk materials according to the appearance of the components, and verify the back pattern of the components to determine the material code. Then, package the verified bulk materials in an anti-static bulk box or bag, and mark the material code with the signature of the confirming person. 3. The loose materials generated on duty should be loaded 1 hour before work or when there are still 100 pieces left on the task order. When the loose materials are online, the operator first checks the material code and ba
First of all, let's talk about the difference: through holes are drilled holes on PCBs, usually used for interlayer conductivity and also for heat dissipation. A pad is a pad on a via, just like a pad for inserting devices. But! In the production and manufacturing process of PCB circuit boards, their processing methods are different. 1. The number of holes indicated in the design of VIA is determined by drilling. Then there are also process steps such as copper deposition, and the actual pore size will be approximately 0.1mm smaller than the designed pore size. For example, if the through-hole is set to 0.5mm, the actual aperture after completion is only 0.4mm. 2. The aperture of PAD will increase by 0.15mm during drilling. After undergoing copper deposition process, the aperture is slightly larger than the designed aperture, about 0.05mm. For example, if the designed aperture is 0.5mm, the drilling will be 0.65mm, and the completed aperture will be 0.55mm. 3. VIA may be co
SMT processing is the most common technology in the SMT processing industry. What questions do we need to know about such a process? How can we comprehensively understand the technology of SMT processing? How can we comprehensively understand the factors that contribute to these problems? Here are a few points for you: 1： Placement of SMT processing: Its function is to accurately install surface mounted components onto the fixed position of the PCB. The equipment used is a placement machine, located behind the screen printing machine in the SMT production line. 2： Screen printing for SMT processing: Its function is to leak solder paste or SMT adhesive onto the PCB pad, preparing for the welding of components. The equipment used is a screen printing machine (screen printing machine), located at the forefront of the SMT production line. 3： Solidification of SMD processing: Its function is to melt the SMD adhesive, thereby firmly bonding the surface assembled components with the PC
The current management situation of small and medium-sized enterprises in China can be divided into three types: first, management without management; Secondly, there is management, but the form of expression is relatively extensive; The third is to have management, but it is not the crystallization of the natural development of one's own enterprise, but rather a product that is "borrowed" and basically belongs to the type of "copying and copying". 1. There is no "management" management, which means that enterprises do not have a fixed management model and rely solely on command and command to act. In this type of enterprise, there is no organizational structure, no clear division of labor, and often an employee has to hold multiple positions, with the element of human governance running through it. The management of the enterprise relies entirely on the consciousness of family relationships, and commands or commands fill the entire process of enterprise management. Usually, there
The exceptionally weak quality control and technical management in circuit board factories can lead to product quality problems. The quality department and technical department are important in circuit board enterprises, and most circuit board factories with abnormal quality have a common point, which is chaotic internal management. So, in order to improve product quality and reduce manufacturing costs, the circuit board sampling manufacturer tells you that the circuit board factory should have made improvements in the following aspects: 1. Everyone has responsibilities and everything has a process The circuit board factory should clarify the functions and job responsibilities of the technical and quality departments, especially for order review, product process drawings, FPC/PCB inspection standards, etc., to avoid the production and material departments from privately changing information. The biggest taboo in management is to rely on power for management. Circuit board factories
1、 PCB copying material Taking ordinary double-sided sheet metal as an example, sheet materials generally include FR-4, CEM-3, etc., with sheet thicknesses ranging from 0.6mm to 3.0mm, and copper thicknesses ranging from frac12oz to 3oz, all of which cause significant price differences in sheet metal; In terms of solder resist ink, there is also a certain price difference between ordinary thermosetting oil and photosensitive green oil. 2、 PCB board copying production process Different production processes can result in different costs, such as gilded and tinned plates, gongs (milled) and beers (punched) plates for manufacturing shapes, and the use of silk screen and dry film circuits. 3、 PCB copying difficulty Even if the materials and processes are the same, the difficulty of the PCB itself will result in different costs. If there are 1000 holes on both types of circuit boards, and one board has a hole diameter greater than 0.6mm and the other board has a hole diameter less t
In recent years, Pcb liquid medicine has gradually shifted from being environmentally friendly to being environmentally friendly. The government has increased its punishment efforts, and the industry and PCB manufacturers or suppliers have begun to pay close attention to environmental issues. Environmentally friendly chemical solutions emit less exhaust gas, wastewater, and waste, making them easy to handle, creating a friendly working environment, and providing more protection for workers' physical health. For example, in the field of porous metals, in recent years, more and more PCB companies have chosen organic conductive film direct electroplating. This metallization process does not emit formaldehyde gas, which not only greatly improves the working environment, but also has no complex wastewater and simple treatment methods, greatly saving water and electricity, and reducing operating costs. Wise individuals in the PCB industry have begun to call for innovation in the PCB sa
PCB circuit board impedance refers to the parameters of resistance and reactance, which hinder AC power. In the production of PCB circuit boards, impedance processing is essential. The reasons are as follows: 1. PCB circuits (bottom of the board) should consider the installation of electronic components by plugging, and after plugging, issues such as conductivity and signal transmission performance should be considered. Therefore, it is required that the impedance should be as low as possible, and the resistivity should be less than 1&TIMes per square centimeter; Below 10-6. 2. During the production process of PCB circuit boards, they need to go through processes such as copper deposition, electroplating tin (or chemical plating, or thermal spraying tin), and connector soldering. The materials used in these processes must ensure a low resistivity to ensure that the overall impedance of the circuit board meets product quality requirements and can operate normally. 3. The tin plat
What is a circuit board Printed Circuit Board, commonly known as PCB, is a complex manufacturing process that involves dozens of processes such as inner layer, pressing, and drilling. It is generally classified according to the number of layers and characteristics, and can be divided into three types based on the number of layers: single-layer board, double-layer board, and multi-layer board. Single panel refers to a circuit board where wires are concentrated on one side, Double panel refers to a circuit board with wires distributed on both sides, while multi-layer single refers to a circuit board with more than two sides. Circuit board classification: 1. Flexible board 2. Rigid plate 3. Soft hard combination board Circuit boards can be divided into three main categories based on their characteristics: flexible boards, rigid boards, and soft hard composite boards. Flexible boards, also known as FPCs, are mainly made of flexible substrate materials such as polyester film, whic
1. Design considerations Firstly, before starting the design, it is necessary to understand the copper PCB specified in the design guidelines. From the shared guidelines, it can be understood that it includes considerations such as line width, line spacing, and heat release mode. The increased copper thickness requires wider wiring to accommodate higher currents, and appropriate spacing is crucial for avoiding hot spots and ensuring reliable operation. In addition, selecting suitable materials with excellent mechanical strength and thermal performance is crucial for ensuring robustness. 2. Material selection Careful attention must be paid to the etching process to prevent excessive etching, which may damage the integrity of the copper layer. In addition, the additional weight of copper requires a sturdy substrate to support the structure of the board. You may have a question why industrial power supplies require the use of thick copper plates because they have exceptional heat
In circuits with resistors, inductors, and capacitors, the resistance to alternating current is called impedance. Impedance is commonly represented by Z, which is a complex number. The real part is called resistance, and the imaginary part is called reactance. The impedance caused by capacitors in a circuit is called capacitance, while the impedance caused by inductors in a circuit is called inductance. The impedance caused by capacitors and inductors in a circuit is collectively called reactance. The unit of impedance is ohms. Impedance type (1) Characteristic impedance In electronic information products such as computers and wireless communication, the energy transmitted in the circuit of a PCB is a square wave signal (pulse) composed of voltage and time, and the resistance it encounters is called characteristic impedance. (2) Differential impedance Two identical signal waveforms with opposite input polarity at the driving end are transmitted by two differential lines, and t
a) Ma Keng: Ma Keng is the result of organic pollution. Large pits usually indicate oil pollution. If the stirring is poor, the bubbles cannot be expelled, which will form pits. Wetting agents can be used to reduce its impact. We usually refer to small pits as pinholes. Poor pre-treatment, metallic impurities, low boric acid content, and low plating temperature can all cause pinholes. Maintenance and process control of the plating solution are crucial, and anti pinhole agents should be used as process stabilizers to supplement. b) Roughness and burrs: Roughness indicates that the solution is dirty, and sufficient filtration can correct it (high pH can easily form hydroxide precipitates, which should be controlled). If the current density is too high, impurities are brought in by impure anode mud and added water, and in severe cases, roughness and burrs will occur. c) Low adhesion: If the copper coating is not fully removed from the oxide layer, the coating will peel off and the adh
Benefiting from the rotational support of terminal new products and new markets, the global PCB market has successfully achieved recovery and growth. According to data from the Hong Kong Circuit Board Association (HKPCA), the global PCB market will develop steadily in 2011, expected to grow by 6-9%, while China is expected to grow by 9-12%. The Taiwan Institute of Industry and Technology (IEK) analysis report predicts that the global PCB output value will increase by 10.36% in 2011, with a scale of 41.615 billion US dollars. According to Prismark's analysis data and the report released by Industrial Securities R&D Center, the changes in PCB application structure and product structure of PCB sampling manufacturers reflect the future development trend of the industry. With the decline in the output value of single/double sided boards and multi-layer boards, as well as the increase in the output value of HDI boards, packaging carrier boards, and soft boards, it indicates that the grow
Single panel Single sided boards are on the most basic PCB, with parts concentrated on one side and wires concentrated on the other side (when there are SMD components, they are on the same side as the wires, and plug-in devices are on the other side). Because wires only appear on one side, this type of PCB is called a single side. Because single panels have many strict restrictions on the design of wiring (as they only have one side, wiring cannot cross and must be routed independently), only early circuits used such boards. Double-sided board Double sided boards have wiring on both sides of the circuit board, but to use wires on both sides, it is necessary to have appropriate circuit connections between the two sides. The "bridge" between these circuits is called a guide hole (via). A guide hole is a small hole filled or coated with metal on a PCB that can be connected to wires on both sides. Because the area of the double-sided board is twice that of a single panel, the doubl
The reason why PCB has been increasingly widely used is because it has many unique advantages, which can be summarized as follows. Can be high-density. For decades, high-density printed circuit boards have developed with the improvement of integrated circuit integration and the advancement of installation technology. High reliability of PCB board sampling. Through a series of inspections, tests, and aging tests, it can be ensured that the PCB can work reliably for a long time (usually 20 years). Designability. The various performance requirements (electrical, physical, chemical, mechanical, etc.) of PCBs can be achieved through design standardization and standardization, with short time and high efficiency. Producibility. By adopting modern management, standardized, scaled, automated production can be carried out to ensure product quality consistency. Testability. We have established a relatively complete testing method, testing standards, various testing equipment and instrum
Entering the PCB prototype factory, the first thing to see is the cutting process, where copper plates of various thicknesses (from 0.4mm to 2.0mm) are cut into appropriate sizes, laying the foundation for circuit board production. This step may seem simple but it is actually very important. If the board size design is not suitable, a lot of edge waste will be generated during the PCB production process. PCB sampling manufacturers will add the price of the waste edge to the customer's board, increasing the unit price. Improving the utilization rate of raw materials as much as possible is an important measure taken by Jiali Chuang to lower the unit price. Then you see the drilling workshop, where the large and small holes on the circuit board are for inserting electronic components or through hole jumpers. This process is completely operated by computer numerical control, and the machine sets the size and coordinates of the through-hole according to the circuit. The accuracy requirem
A multifunctional SMT machine, also known as a high-precision SMT machine or general-purpose machine, can mount high-precision large and irregular components. Generally, it can also mount small chip shaped components, covering almost all component ranges, so it is called a multifunctional SMT machine. Today, let's talk about the basic features of a multifunctional SMT machine: 1、 The structure of functional SMT machines mostly adopts an arch structure, which has the characteristics of high accuracy and good flexibility. 2、 In X and Y positioning systems, full closed-loop servo motors are mostly used for driving, and linear grating encoders are used for direct position feedback to avoid errors caused by screw distortion and deformation. Some use dual electric motors and dual screw rods on both sides of the platform in the y-axis, and use a bilinear grating ruler for feedback, which can effectively reduce the waiting caused by the stationary mounting head and reduce the error cause
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