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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
Multilayer circuit board: refers to a printed circuit board with three or more layers of conductive graphics and insulating materials between them, which are laminated and separated, and the conductive graphics between them are interconnected as required. Multilayer circuit boards are a product of the development of electronic information technology towards high speed, multifunctional, large capacity, small volume, thinness, and lightweight. Single sided circuit board: On the most basic PCB, parts are concentrated on one side and wires are concentrated on the other side. Because wires only appear on one side, this type of PCB is called a single sided circuit board. Single panel production is usually simple and cost-effective, but the disadvantage is that it cannot be applied to products that are too complex. Double-sided circuit board: It is an extension of a single panel. When single-layer wiring cannot meet the needs of electronic products, a double-sided board should be used. Bo
On printed circuit boards, all electrical connections of components are made through solder pads. According to different components and welding processes, pads can be divided into two types: non through hole pads and through hole pads. Non through hole pads are mainly used for welding surface mount components, while through hole pads are mainly used for welding pin type components. So, what are the shapes of solder pads? Next, please come with the editor to understand: 1. Circular pad In PCB sampling, circular pads are the most commonly used type of pad. For through-hole pads, the main dimensions of circular pads are the through-hole size and pad size, and the pad size is generally twice the through-hole size. Non through-hole circular pads are mainly used for testing pads, positioning pads, and reference pads, and their main dimensions are pad sizes. 2. Rectangular pad There are two types of rectangular pads: square and rectangular. The square pad is mainly used to identify
Rigid circuit boards include phenolic paper laminates, epoxy paper laminates, polyester glass felt laminates, and epoxy glass cloth laminates. Flexible printed circuit boards are also known as flexible printed circuit boards or FPCs. Flexible circuit board, also known as FPC or soft board, is a type of printed circuit board that uses polyimide or polyester film as the substrate, has high reliability and flexibility. So, what are the characteristics of flexible circuit boards and rigid circuit boards? 1、 Characteristics of rigid circuit boards: 1. High density. With the improvement of circuit integration and the advancement of mounting technology, high-density printed circuit board technology has become very mature. 2. High reliability. Through a series of inspections, tests, and aging tests, it can be ensured that the PCB works reliably for a long time. 3. Designability. For various performance requirements of PCBs (electrical, physical, chemical, mechanical, etc.), circuit b
Nowadays, the use of PCB multilayer circuit boards on the market has become a popular trend, and in the development of the industry, the ability of many PCB manufacturers to develop and produce PCB multilayer circuit boards has become increasingly prominent. So, what are the requirements for PCB multi-layer circuit board sampling? Below, the editor will analyze for everyone: 1. Requirements for clean appearance. When making samples for PCB multilayer circuit boards, it is necessary to have a flat appearance of the template, no burrs on the edges and corners, and no blistering or delamination between the wires and solder mask. Only in this way can the PCB multi-layer circuit board ensure better welding effect and also ensure that the PCB multi-layer circuit board produced by the PCB manufacturer meets the appearance requirements of actual use. 2. Reasonable process requirements. Before sampling, it is also necessary to study whether the process of PCB multilayer circuit boards is
Many customers often confuse rigid flex bonding boards and IC carrier boards. Let a professional PCB factory provide you with a detailed explanation of rigid flex bonding boards and IC carrier boards? 1. What is a rigid flexure composite plate? Rigid flexible combination board refers to the combination of soft and hard boards, which combines a thin layer of flexible and rigid bottom layers, and then presses them into a single component to form a circuit board. It has the characteristics of being flexible and foldable. Due to the mixed use of multiple materials and multiple production steps, the processing time of rigid flexible composite plates is longer and the production cost is higher. In the PCB sampling of electronic consumer products, the use of rigid flexible combination boards not only maximizes space usage and minimizes weight, but also greatly improves reliability, thereby eliminating many demands for welded joints and fragile wiring that are prone to connection proble
Medical PCB board is the supporting part of circuit components and equipment in electronic products. Even if the circuit schematic design is correct or the printed circuit board design is inappropriate, it can have a negative impact on the reliability of electronic products. So design according to certain principles. 1. The principles that should be followed in the layout design of medical PCB boards: Firstly, consider the size of the medical PCB board. When the PCB size is too large, the printing line will be long, the impedance will increase, the noise resistance will decrease, and the cost will increase; If the PCB size is too small, the heat dissipation effect will be poor, and adjacent circuits will be easily disturbed. After determining the size of the printed circuit board, it is also necessary to determine the location of special components. Then, according to the functional units of the circuit, arrange all components of the circuit. When determining the location of speci
So, how to store the half hole PCB board of the module? Circuit boards are not better than other products and cannot come into contact with gases and water. Cannot damage the module half hole PCB vacuum pump. When loading, place a layer of foam pad beside the small box. Bubble pads have better water absorption ability and are very effective in waterproofing. Naturally, waterproof beads are also essential. Then classify and label the sewage. After opening the packaging, the small box must be separated from the wall, stored off the ground in a dry and cool place, and protected from sunlight. Module half hole PCB boards that have undergone metal surface treatment (such as gold immersion, electroplating, tin spray painting, gold plating, etc.) can usually be stored for 6 months, while module half hole PCB boards that have undergone metal surface treatment (such as silver immersion) can usually be stored for 6 months., Tin, OSP, etc. can usually be stored for 3 months. For module half
Module half hole PCB board. A double-layer PCB circuit board is a type of PCB circuit board formed by bonding a replaced conductive pattern layer and an insulating layer material layer. The number of stacked layers of the conductivity pattern is above three, and the interconnection of fixed layer electrical equipment is completed based on metallized holes. If one double-sided board is used as the inner layer, two single-sided aluminum substrates are used as the outer layer, or two double-sided boards are used as the inner layer, and two single-sided aluminum substrates are used as the outer layer, and the raw materials are bonded together according to the system and insulation layer, and the conductivity pattern is interconnected according to the design plan, it becomes a four or six layer PCB circuit board, also known as a double-layer PCB circuit board. A double panel is a material layer in the middle, and both sides are wiring layers. The double-layer module half hole PCB board
Another reason for this problem is that the composition of the solder wire used throughout the production, processing, and manufacturing process changes, resulting in excessive residue and the need to add pure tin or replace the solder wire. Spot printed laminated glass undergoes changes in the physical state of chemical fiber layers, such as separation between layers. But this type of situation is not due to poor spot welding. The reason is that the base steel plate is too hot, so it is necessary to reduce the heating and soldering wire temperature or increase the driving speed of the base steel plate. In general, the solder wire of the module half hole PCB board appears dark gray, but sometimes there are orange spot welds. The key reason for this problem is that the temperature is too high, and only lowering the temperature of the tin furnace is sufficient. Due to the structure of the PCB itself, it is very easy to cause harm to the module's half hole PCB board when exposed to
The short circuit fault of the module half hole PCB board is one of the common problems that immediately cause the module half hole PCB board to not work. There are many reasons for this type of problem, and everyone will analyze it one by one below. 1) The main reason for PCB short circuit faults is the poor design of the solder pad. In this case, it is possible to change the circular solder pad to an elliptical shape, increase the spacing between points, and avoid short circuit faults. 2) Inappropriate design solutions for PCB component orientation can also lead to short circuit faults on wooden boards and prevent them from working properly. If the foot of a SOIC is parallel to the tin wave, it is very easy to cause a short circuit fault accident. At this time, the orientation of the part can be adjusted appropriately to make it perpendicular to the tin wave. 3) There is also a probability that it can lead to a common fault of PCB short circuit, which is fully automatic softwa
Why do module half hole PCB boards require vacuum packaging bags? Although this issue is small, it is indeed a problem that many circuit board manufacturers attach great importance to. Due to the lack of good sealing performance of the module half hole PCB board, its surface gold deposition, tin spraying, and welding layer positions will be oxidized by air, which poses a threat to welding and is not conducive to production and manufacturing. So, how do you store the module half hole PCB board? A circuit board is not like any other product, it cannot touch gas or water. The module half hole PCB vacuum pump cannot be damaged. When loading, a layer of bubble pad should be placed next to the small box. The bubble pad has good water absorption ability, which has a very good effect on waterproofing. Naturally, waterproof beads are also indispensable. Then classify and label the pollutants. After packing, the small box must be separated from the wall, stored off the ground in a dry and c
The quality and production efficiency of SMT chip placement processing are crucial for PCB circuit boards. If they are the foundation of PCB circuit boards, then SMT process materials are the bricks and stones of PCB circuit boards, playing a crucial role. Therefore, when designing the SMT process and resumes the production line, it is necessary to select appropriate process materials based on the process flow and requirements. SMT process materials include welding and SMT materials such as solder, solder paste, and adhesive, as well as process materials such as flux, cleaning agent, and heat conversion medium. Next, let's introduce the main functions of assembly process materials. (1) Solder and solder paste Solder is an important structural material in surface assembly processes. Different types of solder are used in different applications to connect the metal surface of the welded object and form solder joints. Reflow soldering uses solder paste, which is a welding material an
The SMT installation rate is very important for PCB companies. It can be said that many people are concerned about the SMT installation rate because it not only affects the processing cost of the production line, but also affects the operating speed of the workshop. Today, the editor will introduce to you the impact of suction nozzles on the SMT installation rate! The suction nozzle is also another important factor affecting the installation rate, which can be caused by both internal and external factors. 1: On the one hand, the internal reason is insufficient vacuum negative pressure. Before removing the parts from the suction nozzle, the mechanical valve on the installation head will automatically switch from blowing to true adsorption, resulting in a certain negative pressure. After absorbing the parts, when the detection value of the negative pressure sensor is within a certain range, the machine is normal, and vice versa, the suction is not good. Generally speaking, the nega
A: Component installation offset mainly refers to the position deviation in X-Y after the component is installed on the PCB. The reasons for this are as follows: (1) Reason for PCB board a: The curvature of the PCB board exceeds the allowable range of the device. The maximum upwarping is 1.2mm, and the maximum downwarping is 0.5mm. b: The height of the support pins is inconsistent, resulting in uneven support of the printed board. c: Poor flatness of workbench support platform d: Circuit board wiring has low accuracy and poor consistency, especially with significant differences between batches. (2) The suction pressure of the mounting nozzle is too low, and it should be above 400mmHG when taking out and mounting. (3) Abnormal blowing pressure during installation. (4) Abnormal or deviation in the amount of adhesive or solder paste applied. This leads to displacement during component installation or welding, resulting in deviation from the original position during high-speed
1: The optical recognition system is a fixed optical camera system. During the rotation process of the installation head, the contour of the components is recognized by the camera for optical imaging. At the same time, measure and record the center position and rotation angle of the components relative to the camera, and transmit them to the transmission control system to compare the XY coordinate position deviation and θ， Angle deviation compensation has the advantages of accuracy and flexibility, and is suitable for various specifications and shapes of components. It has a reflection recognition mode based on device electrodes, and the recognition accuracy is not affected by the size of the nozzle. Components such as SOP, QFP, BGA, PLCC generally use reflection recognition mode. The transmission recognition method is based on the shape of the component, and the recognition accuracy is affected by the size of the suction nozzle. When the shape of the suction nozzle is larger than
Printed circuit boards (PCBs) are an indispensable part of electronic devices, and their performance and reliability directly affect the operation of the entire system. PCB (Printed Circuit Board), also known as Printed Circuit Board (PCB) in Chinese, is an important electronic component that supports electronic components and serves as a carrier for the electrical interconnection of electronic components. Due to its use of electronic printing technology, it is called a "printed" circuit board. Cabling is a key step in PCB design, which determines the performance and stability of the circuit board. This article will explore the wiring principles and practical techniques of PCB boards to help engineers achieve better results in design. Wiring principles Following the circuit schematic diagram Wiring should strictly follow the circuit schematic to ensure correct wiring connections and prevent short or open circuit problems. During the wiring process, each component in the circuit
There are many knowledge points about PCB, and it is difficult for one to understand them in a short time, but basic common sense still needs to be learned quickly. So, do you understand the basic knowledge of PCB sampling? 1. PCB measurement unit The unit of measurement for PCBs is usually English units, not metric units. The units of dielectric thickness, conductor length, and width are usually in inches or mils. 1mil=0.001in, 1mil=0.0254mm The thickness of a conductor is measured in ounces (oz, where the mass of a metal conductor refers to the mass of 1 inch of material), Commonly used thickness is 0.5oz=17.5 μ m. 1.0oz=35.0 μ m. 2.0oz=70.0 μ m. 3.0oz=105.0 μ M. 2. Physical characteristics of PCB transmission lines In PCB proofing, the length L and width W of the transmission line are usually set by the PCB layout engineer. The width and spacing of transmission lines are generally not less than 5mil; The thickness H of the transmission line varies depending on the manufac
The high degree of customization is the most important characteristic of PCBs. There are significant differences in the usage scenarios, products, performance, materials, areas, and other aspects of PCBs, resulting in significant changes in the types of components used, the thickness of connecting wires, and the density of wiring. This requires PCB companies to have strong customized production capabilities. Although the PCB industry has some common basic processes, the most important thing is to determine different production processes and equipment based on the accuracy requirements of substrate thickness and material, line width and distance, design structure and production scale, as well as other specific requirements specified by customers, resulting in significant differences in production prices. So, do you know what the cost components of PCB circuit boards are? The production process of PCB is relatively complicated, usually involving more than 40 processes such as inner
1. One side adopts red glue technology, and the other side adopts solder paste technology This method is suitable for PCB boards with dense components and different sizes of components on one side. Especially when the gravity of large components is high, there will be detachment phenomenon after reflow soldering, and at this time, the red glue will become more firm when exposed to heat. The process flow is as follows: incoming material inspection -->A-side screen printing solder paste on PCB -->SMT -->AOI or QC inspection -->A-side reflow soldering -->flip board -->B-side screen printing red glue or dot red glue on PCB (note that both dot red glue and dot red glue apply to the middle part of the component, and do not let the red glue contaminate the solder pad, causing the component feet to not solder) -->SMT -->drying -->cleaning -->testing -->repair. It should be noted that the solder paste surface must be welded first before drying the red adhesive surface. Because the drying t
Wave soldering is a batch soldering process used for manufacturing PCBs. The basic equipment used in this process is to move PCB through conveyors in different areas, solder trays used in the welding process, pumps that generate actual waves, and spray and preheating pads for flux. Solder is usually a mixture of metals. Wave soldering is mainly used for welding through hole components. 1. There is green oil inside the component hole, which leads to poor tin plating inside the hole. The green oil in the hole should not exceed 10% of the hole wall, and the number of holes in the internal green oil should not exceed 5%. 2. Insufficient coating thickness leads to poor tin plating in the hole. 3. The coating thickness on the component hole wall is insufficient, resulting in poor tin plating inside the hole. For example, copper thickness, tin thickness, gold thickness, etc. Usually, the thickness of the hole wall should be greater than 18 μ M. 4. The hole wall is too rough, resulting
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