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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
What matters do customers need to explain to the PCB sampling manufacturer when submitting PCB sampling orders? Next, let the editor tell you. 1. Material: Describe the manufacturing material used for PCB proofing, the most common being FR4, which is mainly epoxy resin peeled fiber cloth board. 2. Board layer: Indicate the number of layers made. 3. Resistance welding color: There are many colors available, which can be selected according to your own requirements, usually green. 4. Silk screen color: The font and border color of the silk screen on the PCB board are generally selected as white. 5. Copper thickness: The thickness of copper is generally scientifically calculated based on the current of the PCB circuit, and generally the thicker the better, but the cost will be higher. 6. Is the through-hole covered with solder mask: solder mask is used to insulate the through-hole, otherwise it will cause the through-hole to become uninsulated. 7. Surface coating: with tin spray
There are many factors that contribute to the price of PCB samples, and it is difficult for new salespeople to quote a standardized price without understanding the factors that contribute to PCB price composition. So, what are the components of PCB quotation? 1. Urgent or not For customers with tight delivery requirements, they can apply for expedited order service. For general single and double sided boards that require 12 hours of expedited delivery, PCB sampling manufacturers may charge an expedited fee of approximately 800 yuan. 2. Invoice fees Some customers' companies have very formal financial procedures, so they need to provide invoices for every PCB procurement project, and invoicing is subject to taxation. Therefore, PCB sampling manufacturers generally add this invoice tax to the PCB sampling price. 3. Express delivery fees Generally, customers with long-term cooperation and relatively close geographical locations will be delivered free of charge by drivers appoint
PCB sampling refers to the production of a small quantity of PCB samples for functional debugging before starting mass production of circuit boards; After the functional debugging is completed, subsequent batch production can be carried out, which can avoid production risks and reduce losses caused by product errors. There are two methods for PCB sampling, namely formal PCB factory sampling and professional sample company sampling. So, what are the differences between the two types of sampling? Next, let the editor tell you. 1. The purpose of regular PCB factory sampling is to have bulk orders and hope that customers can have a return order; Professional sample companies themselves only produce samples or small batches, and if there are large orders, they generally cannot do so. 2. In terms of quality assurance, it is certain that regular PCB factories do better than professional sample companies. Professional sample companies usually charge for samples upon delivery, do not eve
High frequency circuit board refers to a special type of circuit board with high electromagnetic frequency, used for PCBs in the fields of high frequency (frequency greater than 300MHz or wavelength less than 1 meter) and microwave (frequency greater than 3GHz or wavelength less than 0.1 meter). It is a circuit board produced using ordinary rigid circuit board manufacturing methods or special processing methods on microwave substrate copper clad board. Generally speaking, high-frequency boards can be defined as circuit boards with frequencies above 1GHz. High frequency circuit boards are one of the high difficulty boards, so what are the requirements for making high frequency circuit boards? 1、 Drilling 1. The drilling feed speed should be slow, with a speed of 180/S. A new drilling nozzle should be used, with aluminum plates placed on top and bottom. It is best to drill with a single PNL, and the hole should not be exposed to water; 2. The ground plate copper sinking circuit i
The product quality of circuit boards is produced, not inspected. Only by strictly following the production process and operation instructions at every stage of the production process can the quality of the products be guaranteed. Therefore, in the production of PCB circuit board products, circuit board manufacturers must do the following 8 points: Firstly, establishing the awareness that quality is the lifeblood of an enterprise To recognize: poor product quality; Products have no market, products have no market, and enterprises lose their source of profit. Of course, for companies, even if the product market is good, they should "be prepared for danger", improve product quality, and create a better corporate reputation. Secondly, establish a customer awareness of quality Everything is customer-centric, treating oneself as the customer, the operator of the next process, and the consumer of the product. If you cut corners in your work, it will harm your personal interests. Thi
What problems will you encounter when designing circuit board samples? The following is a summary of ten common problems encountered in PCB sample design. 1、 Overlap of pads Overlapping solder pads means overlapping holes. During the drilling process, multiple drilling at one location can cause damage to the holes and result in scrapping. 2、 Graphic layer abuse Specific performance: Some useless connections were made on some graphics layers, and originally a four layer board was designed with circuits above five layers, which caused misunderstandings; Violation of conventional design, such as component surface design at the Bottom layer and welding surface design at the Top, causing inconvenience, etc. Therefore, maintaining the integrity and clarity of the graphic layer during design. 3、 Character shuffling Specifically, the character cover solder pad SMD solder pad brings inconvenience to the on/off testing of circuit boards and the welding of components; Also, the characte
Aluminum substrate is a metal based copper clad plate with good heat dissipation function, commonly used for making LED lights. Let's now understand the difficulties and production specifications of the aluminum substrate production process. 1. Aluminum substrates are often used in power devices with high power density, so copper foil is relatively thick. If copper foil above 3oz is used, the etching process requires engineering design line width compensation. 2. The aluminum substrate surface of the aluminum substrate is protected with a protective film in advance during PCB processing, otherwise some chemicals may corrode the aluminum substrate surface and cause appearance damage. 3. The milling cutter used in the production of fiberglass board has a relatively low hardness and fast milling speed; The milling cutters used in the production of aluminum substrates have high hardness, and the milling cutter speed is at least two-thirds slower. 4. To produce fiberglass panels, on
l. Areas with unreasonable design are most prone to malfunctions What are the unreasonable design aspects of industrial circuit boards? Firstly, there is a heat dissipation issue, as many circuit boards are damaged due to poor heat dissipation design; Secondly, the copper foil wire of the printed circuit board is used. The copper foil of the power supply wire of the circuit board with poor quality is very thin, which is easily burnt off due to overcurrent, making the motherboard unable to work. 2. Frequently used areas are prone to malfunctions For example, the drive motor of industrial circuit boards, rotating shafts, switch tubes of switching power supplies, commonly used buttons on operation panels, etc. 3. Components with heavy loads, high power, and high operating voltage are most likely to malfunction The power supply, drive circuit, power control device, operational amplifier, etc. of industrial circuit boards are the most vulnerable to damage. These components are gene
In PCB design, wiring is an important step in completing product design, and it can be said that the previous preparation work was done for it. PCB wiring includes single-sided wiring, double-sided wiring, and multi-layer wiring. There are also two types of wiring methods: automatic wiring and interactive wiring. Today, let professional engineers explain in detail what PCB wiring rules and techniques are available for you? 1. Handling of power and ground wires The interference caused by improper handling of power and ground wires can lead to a decrease in product performance, and sometimes even affect the success rate of the product. Therefore, the wiring of power and ground wires should be taken seriously, and the noise interference generated by the power and ground wires should be minimized to ensure the quality of the product. The specific approach is as follows: (1) Add a coupling capacitor between the power supply and ground wire. (2) Try to widen the width of the power a
Copper deposition is the abbreviation for chemical copper plating, also known as through hole plating, abbreviated as PTH. It refers to the chemical deposition of a thin layer of chemical copper on a non conductive hole wall substrate that has been drilled, to serve as the substrate for subsequent copper plating. So, what are the processes for copper deposition on PCB circuit boards? Let's take a look together with the editor: 1、 Decomposition of PTH process: Alkaline degreasing → Second or third stage countercurrent rinsing → Coarsening (micro etching) → Second stage countercurrent rinsing → Pre leaching → Activation → Second stage countercurrent rinsing → Gelation → Second stage countercurrent rinsing → Copper precipitation → Second stage countercurrent rinsing → Acid leaching. 2、 Detailed process explanation of PTH: 1. Alkaline degreasing: Remove oil stains, fingerprints, oxides, and dust inside the holes on the board surface; Adjust the pore wall from negative charge to pos
Filtering technology is an effective measure to suppress interference, especially in dealing with conducted interference and certain radiated interference of EMI signals in switching power supplies, which has obvious effects. So, what issues should we pay attention to regarding PCB circuit board filtering technology? 1. Differential mode interference and common mode interference Any conducted interference signal on the power line can be represented by differential and common mode interference signals. In general, the amplitude of differential mode interference is small, the frequency is low, and the interference caused is relatively small; Common mode interference has a large amplitude and high frequency, and can also generate radiation through wires, resulting in significant interference. Therefore, in order to weaken conducted interference, the EMI signal should be controlled below the limit level specified in relevant EMC standards. In addition to suppressing interference sou
Firstly, distinguish the quality of FPC circuit boards from their appearance: 1. Standards for size and thickness. Customers can measure and check whether the product meets the thickness and specifications specified in the production drawings. 2. Light and color. Circuit boards are all covered with ink. If the color of the board is not bright and there is less ink, it indicates that the quality of the board itself is not good. 3. Weld appearance. Due to the large number of parts on the circuit board, poor welding can lead to parts falling off easily. Careful identification can provide a preliminary assessment of quality. Secondly, high-quality FPC circuit boards have the following requirements: 1. It is required that the components be easy to use after installation, that is, the electrical connection should meet the requirements; 2. The line width, thickness, and distance of the line meet the requirements to avoid heating, open circuit, and short circuit of the line; 3. T
1. SIG GND (PWR) - PWR (GND) - SIG; 2. GND SIG (PWR) - SIG (PWR) - GND; The potential issue with the above two stacked designs is the traditional 1.6mm (62mil) plate thickness. The interlayer spacing will become large, which is not conducive to controlling impedance, interlayer coupling, and shielding; Especially, the large spacing between the power layers reduces the board capacitance, which is not conducive to filtering out noise. The first solution is usually applied in situations where there are many chips on the board. This solution can achieve good SI performance, but it is not very good for EMI performance. It mainly needs to be controlled through wiring and other details. The second solution is usually applied in situations where the chip density on the board is low enough and there is sufficient area around the chip. In this scheme, the outer layer of the PCB is a layer, and the middle two layers are both signal/power layers. From the perspective of EMI control, This
For two-layer boards, controlling EMI radiation is mainly considered from wiring and layout; The electromagnetic compatibility issues of single-layer and double-layer boards are becoming increasingly prominent. The main reason for this phenomenon is that the signal circuit area is too large, which not only generates strong electromagnetic radiation, but also makes the circuit sensitive to external interference. The simplest way to improve the electromagnetic compatibility of the circuit is to reduce the loop area of key signals; Key signals mainly refer to signals that generate strong radiation and signals that are sensitive to external boundaries. Single and double layer boards are typically used in low-frequency simulation designs below 10KHz: 1) Route the power supply in a radial pattern on the same layer and minimize the total length of the lines; 2) When using power and ground wires, approach each other closely; Lay a ground wire next to the critical signal line, which sho
The heat generated during the operation of electronic devices rapidly increases the internal temperature of the equipment. If this heat is not dissipated in a timely manner, the equipment will continue to heat up, and the reliability of electronic devices will decrease. Therefore, heat dissipation treatment for circuit boards is very important. So, what are the cooling methods for PCB circuit boards? 1. High heating device with heat sink and heat conduction plate. When there are a few components in the PCB that have a large heat output (less than 3), a heat sink or heat transfer tube can be added to the heating device; When the temperature cannot drop, a radiator with a fan can be used to enhance the heat dissipation effect. When there are a large number of heating devices (more than 3), a large heat dissipation cover (plate) can be used, and the heat dissipation cover can be buckled onto the surface of the components as a whole to dissipate heat in contact with each component. 2.
There is an old saying: PCB design involves 90% layout and 10% wiring. So, what are the skills for PCB wiring? 1. Don't rely on your automatic router Almost all PCB design software has a tool called an automatic router, but an automatic router will never replace itself in wiring and should only be used for a few reasons, including: Accurate. After placing all components, an automatic router can be used to view the completion level obtained. Bottleneck. You can also use an automatic router to discover bottlenecks and other critical connection points that may not be visible during component placement. Inspiration. You can use an automatic router as a source of inspiration to understand how to route some traces that you cannot complete. In addition to the above reasons, it is recommended not to rely on automatic wiring to complete all wiring on the layout of the circuit board. 2. Understand the manufacturer's specifications Before starting to lay copper wiring, please call or
1. Parasitic capacitance The through-hole itself has parasitic capacitance to the ground. If the diameter of the isolation hole on the floor layer of the through-hole is known to be D2, the diameter of the through-hole pad is D1, the thickness of the PCB board is T, and the dielectric constant of the board substrate is ε， The parasitic capacitance of the via is approximately C=1.41 ε TD1/(D2-D1). The main impact of parasitic capacitance on the circuit caused by vias is that it prolongs the rise time of the signal and reduces the speed of the circuit. For example, for a PCB board with a thickness of 50Mil, if a through-hole with an inner diameter of 10Mil and a pad diameter of 20Mil is used, and the distance between the pad and the ground copper area is 32Mil, we can approximately calculate the parasitic capacitance of the through-hole using the above formula as follows: C=1.41 × four point four × zero point zero five zero × 0.020/(0.032-0.020)=0.517pF The variation in rise time
Through holes (via) are an important component of PCB circuit boards, and the cost of drilling holes usually accounts for 30% to 40% of PCB manufacturing costs. Simply put, every hole on a PCB can be referred to as a through hole. So, what are the classification and composition of through-holes on PCB circuit boards? 1、 Classification of vias From the perspective of function, vias can be divided into two categories: one is used as electrical connections between layers; The second is used for fixing or positioning components. From a process perspective, through holes can be further divided into three categories: blind holes, buried holes, and through holes. Blind holes are located on the top and bottom surfaces of circuit boards, with a certain depth, used for connecting surface and inner circuits. The depth of the holes usually does not exceed a certain ratio (aperture). The buried hole is a connecting hole located on the inner layer of the circuit board, and it will not extend
High frequency board refers to a special type of circuit board with high electromagnetic frequency, used for PCBs in the fields of high frequency (frequency greater than 300MHz or wavelength less than 1 meter) and microwave (frequency greater than 3GHz or wavelength less than 0.1 meter). It is a circuit board produced on a microwave substrate copper clad board using partial processes of ordinary rigid circuit board manufacturing methods or special processing methods. Generally speaking, high-frequency boards can be defined as circuit boards with frequencies above 1GHz. So, what are the main factors to consider when choosing a suitable high-frequency PCB board? Let the editor decrypt it for you: 1. Manufacturability; For example, how about the multiple pressing performance, temperature performance, CAF/heat resistance, mechanical toughness (good reliability), and fire resistance level; 2. Various performance matching with the product (electrical, performance stability, etc.); Lo
1、 Contact the manufacturer Firstly, it is necessary to inform the manufacturer of the documents, process requirements, and quantity. Regarding "What parameters do you need to provide for PCB circuit board sampling to the manufacturer?" You can click on this article to learn and provide the necessary information. Then, professionals will provide you with quotations, place orders, and follow up on the production progress. 2、 Material cutting Purpose: According to the requirements of the engineering data MI, cut into small production pieces on large sheets that meet the requirements, and produce small pieces that meet the customer's requirements. Process: Large plate material → Cutting according to MI requirements → Curing plate → Fillet angle/edge grinding → Plate discharge 3、 Drilling Purpose: Based on engineering data, drill the required hole diameter at the corresponding position on the sheet material that meets the required size. Process: Stacking pin → Upper plate → Dril
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