3 Types Of Printed Circuit Board Fabrication Process Flow
A printed circuit board (PCB) is a type of circuit board that emerged in the early 20th century as an electronic component. It allows various electronic components and conductors to be created through a printing process, thereby forming circuits with specific functions. Its characteristics include high wiring density, lightweight, thin thickness, and good flexibility. The manufacturing process of PCBs mainly involves three types: single-sided PCB fabrication, double-sided PCB fabrication, and multi-layer PCB fabrication. If you want to order PCB product, please check and custom your order online. Single-Sided PCB Fabrication Process:Single-sided copper-clad board --> Cutting --> (Etching, Drying) --> Drilling or Punching --> Screen printing of circuit resist pattern or using dry film -> Curing, Inspection, Repair --> Copper etching --> Removal of resist, Drying --> Etching of resist pattern --> Screen printing of solder mask pattern (usually green) with UV curing --> Screen printing of component markings, UV curing --> Preheating, Punching and profiling --> Electrical continuity and short circuit testing --> Cleaning, Drying --> Precoating with solder flux and anti-oxidation agent (Drying) or Hot air solder leveling (HASL) --> Inspection, Packaging --> Final product delivery Double-Sided PCB Fabrication Process:Double-sided copper-clad board --> Cutting --> Lamination -> CNC drilling of through-holes --> Inspection, Deburring, Cleaning -> Chemical copper plating (through-hole metallization) -> (Full-board copper electroplating) -> Inspection, Cleaning -> Screen printing of negative circuit pattern, curing (dry film or wet film, exposure, development) -> Inspection, Repair --> Electroplating of circuit pattern --> Tin plating (nickel/gold for corrosion resistance) -> Removal of ink (photoresist) -> Copper etching -> (Desoldering) -> Cleaning -> Screen printing of solder mask pattern, typically thermosetting green mask (applying photoresist or dry film, exposure, development, thermosetting) -> Cleaning, Drying -> Screen printing of component markings, curing --> (Tin spraying or applying organic solderability preservatives) -> Profiling -> Cleaning -> Electrical continuity and insulation testing -> Inspection, Packaging -> Final product delivery Multi-Layer PCB Fabrication Process (Using Through-Hole Plating):Manufacturing process for multi-layer boards using through-hole plating --> Inner layer copper-clad board, double-sided profiling -> Cleaning -> Drilling for hole positioning -> Applying photosensitive etch-resistant dry film or coating with photosensitive etch-resistant agent -> Exposure -> Development -> Etching and resist removal -> Inner layer roughening, deoxidation -> Inner layer inspection -> (Outer layer single-sided copper-clad board circuit fabrication, B-stage bonding sheet, material bonding sheet inspection, hole positioning) -> Lamination -> CNC drilling -> Hole inspection -> Pre-treatment and electroless copper plating -> Full-board copper plating -> Plating inspection -> Applying photosensitive electroplatable dry film or coating with photosensitive electroplatable agent -> Exposure of outer layer base board -> Development, Repair -> Electroplating of circuit pattern -> Electroplating of tin-lead alloy or nickel/gold -> Removal of resist and etching -> Inspection -> Screen printing of solder mask pattern or photosensitive solder mask pattern -> Printing of character patterns -> (Hot air solder leveling or applying organic solderability preservatives) -> CNC profiling -> Cleaning -> Electrical continuity and disconnection testing -> Inspection, Packaging -> Final product delivery.PCBBUY Process in here:https://www.pcbbuy.com/pcb_manufacturing_process.htmlwhat is a single sided pcb?A single-sided printed circuit board (PCB) is a type of circuit board primarily produced through the direct etching of copper foil. It emerged in the early 1950s with the United States as a central hub for its development. This type of PCB is characterized by its high wiring density, lightweight, thin thickness, and good flexibility. These advantages have led to the widespread use of single-sided PCBs in electronic devices, especially those requiring lightness and good flexibility. With the advancement of transistors, single-sided PCBs rapidly gained popularity, becoming one of the mainstream products in the PCB manufacturing industry. Single-Sided Copper-Clad Board:A single-sided copper-clad board is a type of substrate where a layer of metal material, typically copper, is adhered to an insulating material according to specific requirements. It comes in two types: single-sided with a bottom layer and single-sided with a middle layer. This material is predominantly used for making PCBs. It features higher power voltage (8.5V) and lower signal voltage (1.5V). The product attributes include new and hot-selling items with thicknesses of 1.6mm and 2.0mm. This material is widely used in the PCB manufacturing industry due to its excellent conductivity and mechanical strength, meeting the requirements of various electronic devices. PCB Cutting:PCB cutting involves the process of resizing double-sided PCB sheets to the desired dimensions. Standard specifications typically employ PCB boards with a thickness of 1.6mm. Prior to cutting, necessary tools and materials like wooden boards, cardboard, marking pens, rulers, and cutting tools need to be prepared. During the cutting process, a wooden board is placed on the PCB board to be cut, and an outline is drawn along the wooden board using a marking pen. The cutting is then carried out along the drawn outline using a cutting tool. During the process, it's crucial to maintain the perpendicularity of the cutting surface to avoid injury. After cutting, the resulting PCB board should be inspected to ensure compliance with requirements. Inspection aspects include dimensions, labeling, and appearance. PCB boards that meet the criteria can proceed to the next processing steps, while those that don't need to be reworked or discarded. Therefore, precision and carefulness are essential during PCB cutting to ensure that each step meets requirements and the final PCB product quality conforms to standards. PCB Etching and Drying:PCB etching and drying are two critical steps in the PCB manufacturing process. Etching involves the use of specific cleaning agents such as chloride and fluoride solvents, as well as nylon or cloth brushes, to clean the surface of the PCB board from oxidation, dirt, and other impurities. The purpose of the cleaning agents is to remove dirt and impurities from the PCB surface, enhancing the board's conductivity and reliability. Following etching, drying is conducted to remove residual cleaning agents and moisture from the PCB board. Drying methods include natural air drying and hot air drying. Natural air drying entails placing the cleaned PCB board in a well-ventilated area to allow moisture to evaporate naturally. Hot air drying involves using high-temperature airflow through drying equipment to dry the PCB board. During drying, over-heating or extended heating should be avoided to prevent deformation or damage to the PCB board. Drilling or Punching:During PCB manufacturing, drilling or punching operations are performed to create holes that connect various conductive paths on the circuit board. Drilling involves creating small holes of the required dimensions on the PCB board's surface to interconnect various conductive paths. Drilling is executed using drilling machines or laser drilling equipment, following the precise hole placement as per the PCB design requirements. On the other hand, punching involves using punching machines to interconnect two conductive paths. Punching is performed on the PCB board's surface, necessitating accuracy to ensure high-quality interconnections. Whether drilling or punching, both processes are pivotal in PCB manufacturing and require precision and accuracy to ensure the board's quality and reliability. Screen Printing of Circuit Resist Pattern or Use of Dry Film:During PCB manufacturing, screen printing of circuit resist patterns or using dry film techniques are employed. Screen printing of circuit resist patterns involves using screen printing machines to apply resist ink onto the PCB's surface, forming the desired circuit patterns. This process requires specialized screen printing equipment and resist ink to ensure the accuracy and precision of the circuit patterns. Using dry film entails applying a thin film to the PCB surface to protect the circuit patterns from oxidation or corrosion. This step involves utilizing specialized dry film materials and equipment to ensure the quality and precision of the film coverage. Both of these steps are crucial in the PCB manufacturing process, requiring accurate operations to ensure the board's quality and reliability. PCB Curing, Inspection, and Repair:After PCB curing, an inspection process is carried out, and if any issues are detected on the PCB board, repair actions are undertaken. The repair process includes the following steps: Identifying issues: Inspect the cured PCB board and identify any problems, such as faulty connections or missing components.Preparing tools: Gather the necessary tools for repair, including blades, pads, solder, etc.Conducting repairs: Depending on the issues, use appropriate tools for repair. For instance, if there's a faulty connection, use a blade to cut the connection and then use pads and solder to establish a new connection.Testing the repaired PCB board: After completing the repair process, test the PCB board to ensure that the repairs have restored normal functionality.Repair operations require specialized skills and experience. Incorrect handling may lead to PCB board damage or malfunction. PCB Copper Etching:PCB copper etching involves chemically removing unwanted copper conductors from the surface of the copper-clad board to form circuit patterns. This process is achieved using acid solutions such as copper chloride with hydrochloric acid or copper chloride with ammonia solution. Parameters such as temperature, pressure, time, and solution concentration need to be controlled to ensure the etching process operates optimally. The predominant etching equipment is horizontal conveyor spray etching, which involves conveyor methods and spray methods. Removal of Resist and Drying:The removal of resist and drying in PCB manufacturing involves two key steps, outlined below: Removal of Resist: The process involves using chemical stripping or micro-etching methods to remove the resist applied to the PCB board's surface.Drying: After removing the resist, the PCB is placed in a drying chamber to eliminate excess solvents and volatile substances, ensuring that the coating dries and forms a stable protective layer.Both of these steps are integral to the PCB manufacturing process, requiring the selection of appropriate processes and equipment to ensure that the treated PCB board meets requirements. Screen Printing of Solder Mask Pattern (Often Using Green Ink):Screen printing of the solder mask pattern involves applying a layer of solder mask material to the surface of the PCB. This solder mask, often green in color, is used to protect the exposed copper traces and components from oxidation and other environmental factors. The screen printing process utilizes specialized equipment to accurately apply the solder mask material in the desired pattern. UV Curing:UV curing refers to a process where specific materials, such as the solder mask or other coatings on the PCB, are exposed to ultraviolet (UV) light. This exposure triggers a chemical reaction that results in the formation of a stable polymer. UV curing is fast, efficient, and environmentally friendly, making it a widely used method in PCB manufacturing. Screen Printing of Component Markings:Screen printing of component markings involves applying markings, labels, or symbols onto the surface of the PCB to indicate the placement and identification of components. This step is essential for ensuring proper assembly and maintenance of the PCB. PCB Preheating, Punching, and Profiling:PCB preheating, punching, and profiling are three steps in the PCB manufacturing process: PCB Preheating: Preheating is crucial in the PCB manufacturing process. It helps relieve internal stress and deformations within the PCB, enhancing its stability and reliability.Punching: Punching involves using a punching machine to create holes in the PCB. The precision and quality of punching directly impact the overall quality and performance of the PCB.Profiling: Profiling includes cutting, bending, and shaping operations to achieve the desired external shape of the PCB. The accuracy and quality of profiling affect the final quality and performance of the PCB. PCB Electrical Continuity and Short Circuit Testing:Electrical continuity and short circuit testing are conducted to ensure that the circuit connections on the PCB are correct and free from any short circuits that could lead to malfunctions or failures. These tests are essential for guaranteeing the PCB's functionality and reliability. what is a double sided pcb?A double-sided copper-clad board is a type of PCB where two conductive circuit boards are sandwiched with an insulating material in between. Copper foils are then pressed onto both sides, allowing both sides to be used as circuits. Double-sided copper-clad boards are a type of double-layered board and are widely used in PCB manufacturing. This material is commonly used in computer motherboards, where copper is laid on the substrate of the motherboard, and then it is divided into multiple independent units using specific patterns. Circuits are created within each unit, ultimately completing the fabrication of a double-sided circuit board. Layer Stacking:Layer stacking is a step in the PCB manufacturing process where multiple layers of PCBs are stacked in a specific order. In the PCB manufacturing process, layer stacking involves placing multiple layers that need to be laminated in the correct sequence. It is achieved through the process of brownization (also known as blackening), where the PCB, confirmed after inspection, is treated with brownizing solution to create a fuzzy copper surface. This increases roughness and forms an organic oxide layer on the surface, enhancing the contact surface area with the resin and ensuring reliable lamination. CNC Drilling for Through-Holes:CNC drilling for through-holes is a machining process aimed at drilling conductive through-holes on the PCB substrate. Here's the basic process: Mount the drill bit on the CNC drilling machine and place the PCB substrate on the worktable.Determine the positions and sizes of the through-holes.Adjust the drill bit's position and height to align with the through-hole locations.Start the CNC drilling machine to perform the drilling operation.After completing the drilling of through-holes, remove the PCB substrate from the CNC drilling machine. Regularly check the drill bit for wear and replace it if necessary. PCB Deburring and Cleaning:The method for PCB deburring and cleaning is as follows: Manual wiping: Wipe the PCB board using a brush soaked in alcohol or a lint-free cloth. Alternatively, specialized SMT wiping paper can be used to clean the PCB and remove cured solder paste or adhesive. While this method is convenient and cost-effective, it has several drawbacks such as inefficient cleaning, wastage of labor, and the potential for chemical solvents to violate environmental regulations.Equipment cleaning: Add an appropriate amount of cleaning solution, set the cleaning time, machine parameters, and drying time. Place the PCB board on the fixture inside the machine, then start the equipment to perform the cleaning. This method is safe, environmentally friendly, cost-effective (as the cleaning solution can be recycled), and offers high cleanliness up to 99.8%. It ensures thorough cleaning and drying. Chemical Plating (Through-Hole, Electroless Nickel/Gold):Chemical plating involves depositing a metal onto a substrate's surface using specialized plating solutions. Electroless nickel/gold plating is used for through-hole metalization in PCBs. This process deposits metal inside and on the surface of through-holes using chemical reactions, allowing for the connection of different layers of the PCB. This process is also known as hole metallization. While chemical plating offers advantages like coating non-conductive substrates and achieving strong adhesion, it can be costly due to the price of chemicals used. Full-Panel Electroplating of Thin Copper:Full-panel electroplating of thin copper involves depositing a layer of copper onto the entire surface of a PCB to protect the deposited thin copper, preventing its oxidation from being eroded by acid. Simultaneously, the deposited layer is thickened to a certain extent through electroplating. The process for full-panel electroplating of thin copper is as follows: Grinding the board.Pre-immersion.Full-panel electroplating of thin copper.Rinsing.Drying.Descending the tank.Rinsing.Drying.Inspection. Screen Printing Solder Mask Pattern (Often Using Green Ink):Screen printing of the solder mask pattern involves applying a layer of solder mask material to the PCB's surface. This solder mask, often green in color, is used to protect the exposed copper traces and components from oxidation and other environmental factors. The screen printing process uses specialized equipment to accurately apply the solder mask material in the desired pattern. UV Curing:UV curing refers to the process of exposing specific materials, such as solder mask or other coatings on the PCB, to ultraviolet (UV) light. This exposure triggers a chemical reaction that leads to the formation of a stable polymer. UV curing is rapid, efficient, and environmentally friendly, making it widely used in PCB manufacturing. Screen Printing Component Markings:Screen printing component markings involve applying labels, symbols, or identification codes to the surface of the PCB to indicate the placement and identification of components. This step is crucial for accurate assembly and maintenance of the PCB. PCB Preheating, Punching, and Profiling:PCB preheating, punching, and profiling are essential steps in the PCB manufacturing process: PCB Preheating: Preheating relieves internal stress and deformations in the PCB, enhancing its stability and reliability.Punching: Punching involves using a punching machine to create holes in the PCB. The quality of punching directly affects the overall performance of the PCB.Profiling: Profiling includes cutting, bending, and shaping to achieve the desired external shape of the PCB. Accurate profiling is crucial for the final quality and performance of the PCB. PCB Electrical Continuity and Short Circuit Testing:Electrical continuity and short circuit testing ensure that the circuit connections on the PCB are correct and free from short circuits that could lead to malfunctions or failures. These tests are vital to ensuring the functionality and reliability of the PCB. what is a multilayer pcb?A multilayer printed circuit board (PCB) is a type of circuit board used in electronic products that consists of multiple layers of insulation substrate with interconnected traces and solder pads for mounting electronic components. It serves the purpose of conducting signals across different layers while also providing insulation between them. Inner Layer Copper CladdingInner layer copper cladding refers to the addition of inner layers to a double-sided copper-clad PCB. Inner layer copper cladding allows for precise control of the thickness of inner layer PCB copper foils and control of controlled impedance for signal transmission. This can effectively enhance the quality of transmission for high-speed digital and high-frequency RF signals. Double-Sided Routing for Inner Layer Copper CladdingDouble-sided routing for inner layer copper cladding involves precision machining of the inner layer copper-clad PCB to create openings on both sides, facilitating further processing and manufacturing. Inner layer copper cladding is mainly used for connecting, securing, and testing electronic components. It can also provide functions such as electromagnetic shielding and heat dissipation. Drill Hole PositioningDrilling is carried out using a drill press, and the steps include: Preparing tools, including a drill press, fixture, center drill, etc.Installing the fixture and adjusting its position to align with the drill press spindle.Preparing the center drill and adjusting its protrusion length in the drill chuck.Fixing the fixture to the drill press spindle.Adjusting the drill press speed, running without load to check for smooth rotation.Placing the center drill on the surface of the workpiece.Starting the drill press and drilling holes according to the fixture's hole positioning.Upon reaching the desired depth, retracting the drill bit.Cleaning up the debris. Applying Photosensitive Anti-Corrosion Dry Film or Coating Photosensitive Anti-Corrosion AgentPhotosensitive anti-corrosion dry film or coating photosensitive anti-corrosion agent is used during the PCB fabrication process for corrosion resistance. Photosensitive anti-corrosion dry film is applied on a PET film, and after exposure to ultraviolet light, the exposed areas are dissolved using a developing solution. The remaining resin in the unexposed areas is retained, and the unexposed copper layer is removed through etching, forming the desired pattern. Coating photosensitive anti-corrosion agent involves applying a layer of such agent, followed by a layer of resin, and then curing it with UV light. PCB ExposurePCB exposure involves placing various materials that need exposure under sunlight or ultraviolet light to evenly project their images onto photosensitive material, creating a photosensitive, developing, or imaging effect. Exposure in PCB fabrication refers to using UV radiation to expose the resist areas of the PCB after silk screening. The exposed areas undergo a polymerization reaction. Subsequently, during the development process, the unexposed resist is removed using a developing solution, leaving behind the polymerized areas, creating the required solder mask pattern on the PCB. PCB DevelopmentDevelopment in PCB fabrication refers to the process of using chemicals, typically alkaline developer, to remove the unexposed resist material from the PCB surface. The alkaline developer dissolves the chemicals in the unexposed areas of the photosensitive film, exposing the underlying copper layer. Different types of developers are used based on the type of photosensitive film used. Etching and StrippingEtching and stripping are two different processes with distinct purposes and applications: Etching: After exposure and development, the protective film is removed from the areas that need to be etched. The board is then subjected to a chemical solution that dissolves the exposed copper areas, resulting in the formation of desired patterns.Stripping: During development, the chemical solution removes the protective film from the unexposed or inadequately exposed areas that are not supposed to be etched. Inner Layer Processing and Oxide RemovalInner layer processing involves increasing the roughness of inner layer traces after edge grinding to enhance adhesion between dry film and the substrate. Oxide removal is performed on the copper surface of inner layer traces after they are completed, aiming to improve solderability and copper plating quality. Inner Layer InspectionInner layer inspection includes: Verifying correct layer definitions.Checking that inner layer routing compensation matches the data.Ensuring independent pads on inner layer traces are properly removed.Checking for added teardrops on pads with line widths smaller than 24 mils.Inspecting via hole clearance and minimum distance from the edge.Verifying the correctness of markings on inner layer films.Inspection of Outer Layer Copper Cladding, B-stage bonding sheets, and bonding sheet material, and drilling positioning holes. Lamination Lamination is a process used to create multi-layered printed circuit boards (PCBs). Before lamination, the inner layers of the PCB undergo extreme temperatures and pressure. Then, a photosensitive dry film resist is laminated onto the surface, followed by curing at high temperatures. Finally, pressure is slowly released, and the laminated material is gradually cooled. Numerical Control Drilling The steps involved in numerical control drilling are as follows: Line Marking: Use tools to mark the centerline of hole positions according to the basic drilling standard requirements. The centerline should be clear and accurate. Measure the marked lines using calipers or steel rulers.Grid or Circular Marking: After marking lines and verifying their accuracy, create a grid or circle centered on the hole centerline. This serves as a reference for checking and correcting hole positioning during drilling.Punching a Sample Hole: Start by punching a small point on the cross centerline in different directions. This helps ensure that the punched hole is precisely located at the intersection of the cross centerlines. Gradually enlarge the sample hole to achieve accurate alignment.Clamping: Clean the machine table, fixture surface, and workpiece reference surface with a cloth. Then securely clamp the workpiece, ensuring it is flat, firm, and easy to inspect and measure. Pay attention to the clamping method to prevent workpiece deformation.Trial Drilling: Before drilling the actual holes, conduct trial drilling. Align the drill bit with the center of the hole and drill a shallow pit at the location of the sample punched hole. Visually inspect the alignment of the pit and make necessary adjustments to achieve coaxial alignment. Hole Inspection Hole inspection refers to the measurement of positional tolerance for each hole in a given product before the manufacturing process. It's a method of controlling the production process to ensure that all hole dimensions, shapes, and relative positions meet the required specifications. The steps of hole inspection include: Line Marking: Use tools to mark the centerline of hole positions. The centerline should be clear and accurate. Measure the marked lines using calipers or steel rulers.Grid or Circular Marking: After marking lines and verifying their accuracy, create a grid or circle centered on the hole centerline. This serves as a reference for checking and correcting hole positioning during drilling.Punching a Sample Hole: Start by punching a small point on the cross centerline in different directions. This helps ensure that the punched hole is precisely located at the intersection of the cross centerlines. Gradually enlarge the sample hole to achieve accurate alignment.Clamping: Clean the machine table, fixture surface, and workpiece reference surface with a cloth. Then securely clamp the workpiece, ensuring it is flat, firm, and easy to inspect and measure. Pay attention to the clamping method to prevent workpiece deformation.Trial Drilling: Before drilling the actual holes, conduct trial drilling. Align the drill bit with the center of the hole and drill a shallow pit at the location of the sample punched hole. Visually inspect the alignment of the pit and make necessary adjustments to achieve coaxial alignment. Pre-Treatment and Electroless Copper Plating for Holes Pre-treatment before electroless copper plating is an important step to enhance the adhesion between the substrate and the copper layer. The process includes the following steps: drilling, alkaline cleaning, water rinsing, acid etching, water rinsing, activation, water rinsing, acceleration, water rinsing, and electroless copper plating. Full Panel Electroplating of Thin Copper Parameters for full panel electroplating of thin copper include: Bath Composition: The main components are copper sulfate and sulfuric acid. A high acid to low copper formula is used to ensure even thickness distribution on the plated surface and the ability to plate deep holes and small holes effectively.Sulfuric Acid Concentration: Typically around 180 g/L, sometimes up to 240 g/L. Copper sulfate concentration is generally around 75 g/L. A small amount of chloride ions is added to the bath as auxiliary brighteners and leveling agents for enhancing the gloss effect.Copper Brightener: The addition or replenishment of copper brightener is generally done at a rate of 3-5 ml/L or according to ampere-hour method based on actual production requirements.Current Calculation: The current for full panel electroplating is usually calculated as 2 A/dm² multiplied by the plated surface area on the board. PCB Plating Inspection Methods for inspecting PCB plating include: Chemical Element Analysis with XRF: Using X-ray fluorescence (XRF) equipment to perform chemical element analysis on PCB materials, including pure copper foil, substrate, etc. This ensures the quality meets required standards and production specifications.Thickness Measurement with XRF Thickness Gauge: Rapid and accurate measurement of thickness for various materials and plated layers on the PCB, such as gold, silver, tin, etc. This ensures proper adhesion of the plating and correct signal transmission.Impurity Detection with XRF Thickness Gauge: Detecting impurities on the PCB surface to exclude defective products and improve production efficiency. Applying Photosensitive Electroplatable Dry Film or Electroplatable Resistant Film The steps for applying photosensitive electroplatable dry film or electroplatable resistant film are as follows: Line Marking: Use tools to mark the centerline of hole positions according to the basic drilling standard requirements. The centerline should be clear and accurate. Measure the marked lines using calipers or steel rulers.Grid or Circular Marking: After marking lines and verifying their accuracy, create a grid or circle centered on the hole centerline. This serves as a reference for checking and correcting hole positioning during drilling.Punching a Sample Hole: Start by punching a small point on the cross centerline in different directions. This helps ensure that the punched hole is precisely located at the intersection of the cross centerlines. Gradually enlarge the sample hole to achieve accurate alignment.Clamping: Clean the machine table, fixture surface, and workpiece reference surface with a cloth. Then securely clamp the workpiece, ensuring it is flat, firm, and easy to inspect and measure. Pay attention to the clamping method to prevent workpiece deformation.Trial Drilling: Before drilling the actual holes, conduct trial drilling. Align the drill bit with the center of the hole and drill a shallow pit at the location of the sample punched hole. Visually inspect the alignment of the pit and make necessary adjustments to achieve coaxial alignment.PCB Surface Layer Exposure PCB surface layer exposure is an important step in the PCB production process. Exposure involves using ultraviolet (UV) light to cure the solder mask on the PCB. Here's how the process works: The PCB with the developed solder mask is placed on the film master.Ultraviolet light is directed through the film master, which has transparent areas that correspond to the solder mask openings.The UV light triggers a chemical reaction in the solder mask material, causing it to harden or cure.After exposure, the unexposed areas of the solder mask are washed away using a developer solution.The hardened areas of the solder mask remain on the PCB surface, protecting the copper traces and components during subsequent processes like soldering and assembly. This process ensures that the solder mask adheres to the desired areas, preventing solder bridges and ensuring proper component placement and soldering during PCB assembly. The quality of exposure affects the accuracy of the solder mask pattern and the overall reliability of the PCB.
PCB Knowledge ⋅ 08/21/2023 15:20
What are the common PCB manufacturing challenges？
Electronics and PCB manufacturing is presently facing several challenges together with opportunities. Along with the need to control costs, the PCB manufacturing services will have to focus on finding ways of capitalizing on current trends. If you are going to learn more about fast turnaround PCB prototype, please check and read the content below for more information.If you want to order PCB product, please check and custom your order online. How Are Prototype PCBs Produced? There are two main methods for prototyping a PCB: Through-hole Technology Through-hole technology is the traditional method of manufacturing PCBs and prototypes. This method involves inserting leads through holes on a single side of the circuit board. Then, the leads are soldered to the copper or other metal layer on the other side. Manufacturers who use through-hole technology often make prototypes by hand. They usually have some issues because they don’t always have all of the same robust components that go into making the final version. These hand-made prototypes tend to be simple in design, and some do not last through the challenges that arise during the testing process. Surface-mounted Technology This method of producing a prototype is more technologically advanced. Surface-mounted technology does not need leads. Instead, the components are soldered in place usually with a speedy soldering technique. SMT allows manufacturers to create more precise, compact boards with complex abilities. Components can be added to both sides of the board because of the soldering technique. These prototypes tend to last through testing procedures because the process makes them stronger than those made through through-hole techniques. SMT prototypes can be made quickly and efficiently. Why to process PCB prototyping? We recommend that you create a prototype before ordering a full production run of a new PCB design. We make sure our prototype PCB service is fast and user-friendly so you can test your board without delay or hassle. Here's what PCB prototyping enables you to do: • Detect design flaws early in the production process before you invest significant capital• Cost-effectively test multiple designs• Get an accurate portrayal of how your board will function What are the common PCB manufacturing challenges？ Electronics and PCB manufacturing is presently facing several challenges together with opportunities. Along with the need to control costs, the PCB manufacturing services will have to focus on finding ways of capitalizing on current trends. This may include integrating technologies outside their primary areas of expertise, while meeting demands from customers for highly efficient manufacturing processes that are also eco-friendly. The biggest trends and challenges in the electronics manufacturing industries are likely to be: Manufacturing is different from designingThe design of your PCB might look good on paper or a computer screen - but it can be an entirely different story when it comes to manufacturing it. For example, there may not be sufficient tolerances between tracks on the board, which later on in the process could result in the circuit shorting out. Or perhaps the design includes a number of components positioned closely together, each with a different thermal mass. Achieving a quality solder joint on each of these components without heat damaging the rest of the circuit board requires expert process engineering skills. Insure the multilayer PCB stackupMultilayer printed circuit boards are those boards that contain more than a single layer counts, hence the need for stack-up. Stack-up is the arrangement of insulating and copper layers to make a printed circuit board before the PCB layout design. What are the main components analyzed during PCB prototype testing? When a PCB prototype is tested, it means that the circuit design of the board is assessed to ensure it’s safe and suitable for your project. The circuit is a combination of electronic components that will be connected by conductive wires within the final PCB design and through which electrical current can flow. These electronic components can include: · Capacitors (C)· Resistors (R)· Diodes (D)· Fuses (F)· Inductor (I)· Integrated Circuit (IC)· Transistor (T)· Relay (R) These are the components that require testing for any faults or irregularities that could lead to PCB failure. It’s also important to ensure they are the ideal type and quality for the given project. For example, it’s important to consider the anticipated environmental conditions (such as temperature and humidity), as well as the available current. Ask yourself: in the case of a short circuit, overload, or overheating, what’s going to happen?Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/21/2023 15:11
What Is Aircon Pcb?-3 Tips
The air conditioner circuit board is one of the essential components of an air conditioner, responsible for controlling the air conditioner's circuits and electronic systems. Through the electronic components and circuit design on the circuit board, functions such as cooling, heating, air supply, and dehumidification of the air conditioner can be achieved. This article will provide a detailed introduction to the structure, working principle, and testing methods of the air conditioner circuit board. If you want to order PCB product, please check and custom your order online. Structure of Air Conditioner Circuit Board The air conditioner circuit board is a vital component of an air conditioner, acting as its neural center and controlling the air conditioner's circuits and electronic systems. The air conditioner circuit board mainly consists of the following components: Power Circuit: The power circuit is the initial stage of the air conditioner circuit board. It is responsible for receiving external power and converting 220V AC power into DC power to supply electricity to the entire circuit board. The power circuit also includes protection devices such as fuses or circuit breakers to ensure safety.Control Circuit: The control circuit is the core part of the air conditioner circuit board, primarily composed of microcontrollers, memory, input-output interfaces, etc. The microcontroller is the heart of the control circuit, responsible for receiving signals from sensors and user inputs. It controls the operation of motor drive circuits and other peripherals based on programs, enabling various functions of the air conditioner. For example, when the indoor temperature exceeds the set value, the microcontroller controls the operation of the cooling motor drive circuit to achieve cooling.Motor Drive Circuit: The motor drive circuit is an important part of the air conditioner circuit board, mainly composed of power driver components, motors, sensors, etc. Power driver components receive signals from the control circuit and drive the motor's operation. For instance, when the control circuit sends a cooling signal, the power driver component drives the cooling motor to operate, achieving the cooling function.Sensor Circuit: The sensor circuit is the perceptive part of the air conditioner circuit board, primarily composed of temperature sensors, humidity sensors, air quality sensors, etc. The temperature sensor detects indoor temperature and the set value, the humidity sensor detects indoor humidity and the set value, and the air quality sensor detects indoor air quality and the set value. These sensors transmit the detected data to the control circuit, which adjusts the operation of motor drive circuits and other peripherals based on programs to achieve various functions of the air conditioner. Working Principle of Air Conditioner Circuit Board Power Supply:The power supply of the air conditioner circuit board is primarily achieved through the power circuit. When the air conditioner is powered on, 220V AC power is input into the power circuit. To ensure safety, protective devices such as fuses or circuit breakers are typically installed on the air conditioner circuit board. Control Circuit:The control circuit of the air conditioner primarily consists of microcontrollers, memory, input-output interfaces, etc. The microcontroller receives signals from sensors and user inputs. It controls the operation of motor drive circuits and other peripherals based on programs, enabling various functions of the air conditioner. For example, when the indoor temperature exceeds the set value, the microcontroller controls the operation of the cooling motor drive circuit to achieve cooling. Motor Drive Circuit:The motor drive circuit of the air conditioner is mainly composed of power driver components, motors, sensors, etc. Power driver components receive signals from the control circuit and drive the motor to operate. For example, when the control circuit sends a cooling signal, the power driver component drives the cooling motor to operate, achieving the cooling function. Sensor Circuit:The sensor circuit of the air conditioner primarily consists of temperature sensors, humidity sensors, air quality sensors, etc. These sensors detect indoor environmental parameters such as temperature, humidity, and air quality. The detected data is transmitted to the control circuit, which then adjusts the operation of the air conditioner's components and functions based on the sensor data. Testing Methods of Air Conditioner Circuit Board To ensure the proper functioning of the air conditioner, it is necessary to test the air conditioner circuit board. The following are common testing methods: Visual Inspection: Begin by visually inspecting the exterior of the air conditioner circuit board for any noticeable signs of burning, damage, or anomalies. If any irregularities are observed, the circuit board may need to be replaced.Voltage Measurement: Use a multimeter to measure the voltage in the power circuit and ensure that it falls within the specified range. If voltage abnormalities are detected, further investigation of the power supply circuit is necessary.Control Circuit Check: Use a multimeter to check the control circuit's functionality. If the microcontroller can control the operation of motor drive circuits and other peripherals based on signals from sensors and user inputs, the control circuit is functioning properly. If it fails to operate correctly, inspect the microcontroller and related circuitry.Motor Drive Circuit Inspection: Use a multimeter to verify the proper operation of the motor drive circuit. If the motor drive circuit can drive the motor when signals are received from the control circuit, the motor drive circuit is working as intended. If the motor cannot be driven properly, inspect the motor drive circuit and related circuit components.Sensor Circuit Examination: Use a multimeter to check the sensor circuit's components. If the sensors can accurately transmit data to the control circuit, the sensor circuit is functioning correctly. If data transmission is not successful, inspect the sensor circuit and related components. In summary, the air conditioner circuit board is one of the core components of an air conditioner, and its proper functioning is crucial for the normal operation of the air conditioner. During air conditioner maintenance, testing the circuit board is necessary to identify the causes of malfunctions and undertake necessary repairs. Additionally, to ensure safety, strict adherence to relevant regulations is necessary during operation.
PCB Knowledge ⋅ 08/19/2023 16:58
What are the testing options of PCB CTI?
The CTI value is tested in accordance with the IEC-112 standard method "Test Method for Comparative Tracking Index of Substrates, Printed Boards and Printed Board Assemblies", which means that the surface of the substrate can withstand 50 drops of 0.1% ammonium chloride The highest voltage value (V) at which an aqueous solution does not form a trace of electrical leakage. According to the CTI level of insulating materials, UL and IEC divide them into 6 grades and 4 grades respectively. If you are a beginner of PCB industry, do you know PCB CTI? Do you know how it works during the PCB manufacturing process? If you are curious about PCB CTI, please check and read the content below for more professional information.If you want to order PCB product, please check and custom your order online. Why to process PCB CTI? HVTR testing and other standard high voltage arcing tests are performed on dry, solid insulation materials. By contrast, CTI testing is performed with liquid applied to the board’s surface. The objective is to evaluate the resistance of the board’s insulation to tracking in the presence of contamination, which is more likely for industrial boards, especially when embedded in production equipment, as found in advanced industrial processing environments. The CTI is important as it provides a quantitative metric by which different materials can be compared and a selection made based upon its probability to withstand its intended environment. Moreover, the CTI can be used to determine creepage and clearance distances for your board’s design. When two PCB traces run in parallel, the dielectric material should not breakdown at any time and both traces should be able to carry current without any problem. The chance of dielectric breaking down and the traces having a direct short is very less. The dielectric ensures that resistance is present between the two traces. One of the primary reasons why the two traces might have leakage current is due to the impurities forming between traces, environmental conditions, voltage applied, and temperature. CTI is the measurement of the susceptibility of the PCB’s insulating material to the electrical breakdown. Mathematically, CTI is that voltage, which results in failure by breakdown after 50 drops of 0.1 percent ammonium chloride solution have fallen on the material. What is the working principle PCB CTI? Comparative Tracking Index (CTI) is the extent to which the insulating material of the PCB can resist the unwanted current to flow between traces on the board. It is a measure of the ability of the PCB substrate to withstand any breakdown between two tracks on the PCB surface. It is used to assess the proportionate resistance of the PCB base material and helps calculate the high-voltage isolation values between the tracks. The CTI value is tested in accordance with the IEC-112 standard method "Test Method for Comparative Tracking Index of Substrates, Printed Boards and Printed Board Assemblies", which means that the surface of the substrate can withstand 50 drops of 0.1% ammonium chloride The highest voltage value (V) at which an aqueous solution does not form a trace of electrical leakage. According to the CTI level of insulating materials, UL and IEC divide them into 6 grades and 4 grades respectively. Copper clad laminates with low CTI values are prone to leakage tracking when used for a long time in harsh environments such as high pressure, high temperature, humidity, and pollution. Generally, the CTI of ordinary paper-based copper clad laminates (XPC, FR-1, etc.) is ≤150, and the CTI of ordinary composite-based copper clad laminates (CEM-1, CEM-3) and ordinary glass fiber cloth-based copper clad laminates (FR-4) It ranges from 175 to 225, which can not meet the higher safety requirements of electronic and electrical products. In the IEC-950 standard, the relationship between the CTI of the copper clad laminate and the working voltage of the printed circuit board and the minimum wire spacing (Minimum Creepage Distance) is also stipulated. The high CTI copper clad laminate is not only suitable for high pollution, It is also very suitable for the production of high-density printed circuit boards for high-voltage applications. Compared with ordinary copper clad laminates with high leakage tracking resistance, the line spacing of printed circuit boards made with the former can be allowed to be smaller. What are the testing options of PCB CTI? The Comparative tracking index is significant as it gives a quantitative metric by which materials that differ can be compared and a selection possible based on its chances to cope with its intended environment. Most especially, the Comparative tracking index can be adopted to ascertain clearance distance and creepage for your board’s design. Comparative Tracking Index Testing OptionsUL testing facility: The best option is by testing by anUl facility if testing is needed. The Comparative tracking index test can be carried out with the related surface tracking estimation.Facility for other testing facilities: There are several companies that can carry out testing of materials for you. The benefit here is that you are not mandated to acquire or have the equipment that is necessary or the environment that meets the standards’ requirements.In-Door: if your anticipation is on the need to carry out this type of testing regularly, the expenses might worth acquiring equipment and expertise to get it done whenever it is required. Additionally, you may make use of the result of past studies that are available, and that is compatible with your design. If accurately utilized, Comparative tracking index testing can assist you in picking the best materials, PCB layout, and coating that are protective for your industrial board.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/19/2023 15:41
What are the considerations of PCB annular ring calculator?
A perfect annular ring will be created by drilling right into the center of the via pad. However, the annular ring may not be in the center because the drilling accuracy depends on the drilling machine used by the PCB manufacturer. There are several drill issues with the annular ring: In this passage, we will tell you everything about annular ring used for PCB. If you are looking for more information about annular ring used for PCB, please check and read the content below for more.If you want to order PCB product, please check and custom your order online. What are the considerations of PCB annular ring calculator? Different fabrication houses will undoubtedly use varied and differing manufacturing technologies and equipment. Average performance houses may offer design specifications allowing a 10mil minimum annular ring. High performance houses may be able to reduce that figure down to 5mil. If pad and via holes are laser-drilled, as opposed to mechanically drilled, then the value for the minimum annular ring may be reduced further still. The class of board you are designing will also play a part in the value required for the minimum annular ring. For example, if your design is of IPC Class 3 standard, which refers to high reliability electronics products, the required minimum annular ring is 2mil. If you do have to reduce the annular ring below the accepted standard of the fabrication house, try to limit the usage of such affected pads and vias. The more pads and vias on the board that use such annular ring specifications, the more chance there is of a board failing during the fabrication process. How to calculate annular ring? To find an annular ring’s width, you need to use this formula: (pad diameter – via diameter) ÷ 2. If the diameter of the pad is 25 mils (0.50mm) and the hole/via is 15 mils (0.38mm) then your equation will look like this: (25 - 15) ÷ 2 = 5 mils(0.50 – 0.38) ÷ 2 = 0.06mm. Let us look at further real-world examples. That will include the annular ring's width for standard vias, micro via, and component holes. Standard Via Generally, a standard via will feature a hole with a diameter of 0.20mm (7.87 mils). On a 0.40mm (15.74 mils) pad, your final equations will look like this: (0.40mm – 0.20mm) ÷ 2 = 0.10mm(15.74 mils – 7.87 mils) ÷ 2 = 3.93 mils Microvia Micro vias are typically smaller than your standard holes. They will have a hole diameter of 0.10mm (3.93 mils). On a pad with a diameter of 0.30mm(11.82mm), your equation will look like this: (0.30mm – 0.10mm) ÷ 2 = 0.10mm(11.82 mils – 3.93 mils) ÷ 2 = 3.93 mils Component Hole As we discussed earlier, component holes tend to be larger than average vias. On a pad with a 1.20mm (47.24 mils) diameter and a 0.80mm (31.50 mils) hole, your equation will look like this: (1.20mm – 0.80mm) ÷ 2 = 0.20mm(47.24 mils – 31.50 mils) ÷ 2 = 7,87 mils What is the application of PCB annular ring? Annular rings are integral elements of a PCB as they create room for solid electrical connections on a board. Without these rings, you will be unable to create reliable connections on your PCB. Issues related to annular rings are problematic and significantly affect the trace continuity and the functionality of the entire board. Unfortunately, some designers ignore the importance of annular rings by creating distorted shapes. When designing annular rings, you should be accurate to avoid drilling off the mark. By doing so, you will eliminate the annular ring tangency. Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/18/2023 16:53
What are the causes of tombstoning in PCB?
As the name suggests, tombstoning resembles those large, sometimes slanted slabs of granite that you’ll find at a cemetery. In the case of a PCB design, tombstoning is typically a surface mount passive component, like a resistor or a capacitor, that partially lifts from a pad on one end. Tombstoning is just one of many issues that can occur during the soldering process when all of your components get attached to a bare board. And since the beginning of PCB manufacturing, tombstoning has been and continues to be an issue. In this passage, please check and read the content below for more tombstoning in PCB.If you want to order PCB product, please check and custom your order online. What are the causes of tombstoning in PCB? Self-alignmentThe placement head of the automatically correct placement machine place the MLCC (such as four per second) quickly in the process of printing solder paste pads, the board surface and placement head will move quickly according to the X and Y coordinates given by the program. And finding the position and place the MLCC on the pad. At this time, although the X and Y coordinates of the center position of the MLCC are correct, the MLCC may be offset by the angle θ due to unevenness of the pad or sliding of the solder paste when placed on the pad during the instant or after the transfer. Subsequently, due to the simultaneous melting of the two solder joints, the uniform tin-dipping force that appears will pull the MLCC back to the correct position. This situation is a more common type of MLCC in the SMT process. SkewingWhen the two solder joints fail to melt at the same time, or the tin-dipping forces at the two points differs greatly, the tin-dipping forces on one of the solder pads will pull the MLCC more diagonally, as in the case of Figure 2, called Skewing. Sometimes, although it is pulled straight, it is completely pulled towards itself, resulting in a virtual welding at one end. What are the factors of tombstoning in PCB? The tombstone defect occurs due to different wetting speeds that result in imbalanced torque. Wetting is when the solder reaches a fluid state to attach a component lead to the pad. Ideally, the solder attaches to both pads while the wetting process is uniform, but unbalanced soldering causes tombstoning. However, a PCB layout tombstone can also occur due to: · Improperly designed solder pads· Inaccurate placement of components· Inconsistent pad size· Presence of nitrogen· Uneven reflow oven temperature· Chip placement being parallel to the reflow oven· Inconsistent heating capacities in the PCB’s materials In early SMT manufacturing, the tombstoning phenomenon was related to infrared reflow (IR) and vapor phase reflow (VPR) welding. In VPR soldering, the temperature rises too fast, causing the solder paste to melt unevenly if the two components' ends have different heat capacities. In IR, the different heat absorption colors at both components' ends melt unevenly and cause tombstoning. How to prevent tombstoning in PCB? There are three main DFM areas to focus on that will help you to prevent tombstoning from occurring on your PCB design: · Footprint pad size: If the pad sizes for your small passive parts are incorrect, it could affect the thermal mass of the solder joints. A pad with less mass will cause the solder to reflow sooner than larger pads. It is important, therefore, to follow industry standards or the manufacturer’s recommended sizes when you build the CAD footprint pads.· Footprint construction: Along with building the pads to the correct size, you also need to ensure the entire footprint for the passive parts is built correctly. If the part is not centered on its origin, it could lead to problems as you saw in the video. You also must ensure that the pads are correctly spaced and that you are using the same size pad for both pins of the part. Again, the key is to follow industry standards and the manufacturer’s recommendations when building your footprints.· Trace routing and power planes: Even if you have a perfectly sized and balanced CAD footprint, there could still be a risk of differing thermal mass between the pads if the routing is not balanced. Connecting one pad with a thin trace while connecting the other pad with a thick trace will create an imbalance in the thermal mass of the two pads. The additional metal will act as a heat sink, causing the solder paste on that pad to melt slower than the other. Embedding a pad within a power plane is even worse, as the larger area of metal will pull more heat with it. Be careful to balance the routing between the two pads as much as possible, and use thermal ties when connecting a pad directly to a metal plane. By following these recommendations, you have a much better chance of avoiding tombstoning of your small passive parts. Here’s another way that you can get some help with your design so that it will be more easily manufactured.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/17/2023 15:52
What are the considerations of making FPGA PCB?
FPGA devices are ubiquitous in new product designs with approximately 100,000 design starts each year. No one argues that there are many benefits offered by FPGA technology. The industry leaders, Xilinx and Altera, both had sales in excess of $1 billion in 2007, with Xilinx approaching $2B. In this passage, we will tell you everything about the FPGA PCB in design process. If you are searching for more professional knowledge, please check and read the content below in this passage.If you want to order PCB product, please check and custom your order online. How can we program FPGA PCB? FPGA is programmable because it is made up of an array of logic blocks that are programmable. These blocks are connected through a hierarchy of interconnects that are reconfigurable and hence allow the blocks to be connected. This is analogous to many logic gates that can be wired in multiple configurations. The logical blocks of FPGA can be configured in multiple ways so that they can perform complex functions or simple logic gates like XOR and AND etc. Most of the FPGA logic blocks also have memory.0 elements like flip flops or complete memory blocks. What are the considerations of making FPGA PCB? 1. Designing a custom FPGA board makes sense if the project will have a short life cycle, high volume, or requires a smaller form factor than you can achieve with COTS FPGA board and PMOD or FMC add-on boards. 2. If the project life cycle exceeds the product lifetime of a DDR memory chip (a couple of years), then designing a custom FMC daughterboard may be a better alternative. 3. Cost is a factor in this decision. Most COTS FPGA boards are somewhat general-purpose, designed for maximum flexibility. If you're making a high-volume, cost-sensitive product, then it is probably worthwhile to make a custom design; but for low-volume you are probably better off concentrating on making a daughtercard. 4. Regardless of which approach you choose, there are certain interfaces that require clear, master documentation: at the interface between the FPGA toplevel I/O pins and the rest of the board, and at the connector interface between boards. These are places where pin locations, internal net names, and external net names sometimes get mismatched and swapped. A table is sufficient documentation; be sure to keep this interface table versioned and under source control. Before sending PCB files to fabrication, print out a copy of this interface table, a copy of the schematic, and a copy of the FPGA pin/pad report. Drag a highlighter across the papers to check off each signal connects where it should. 5. For connectors, I've learned the hard way to provide a mechanical "system drawing" that shows both boards and mating connectors together on a single, dimensioned drawing. I first got burned by a VME connector system where pin "A1" on one connector did not map to pin "A1" on the other connector. I've also seen designers forget that a pair of right-angle connectors results in a mirror image connection (90 degrees + 90 degrees = 180 degrees). This was a problem when I was responsible for the motherboard and several other project managers were responsible for various daughter boards. Then why FPGA is reprogrammable? The FPGAs can be reprogrammed for the implementation of a different logic function. It allows reconfigurable computing which is flexible. The FPGAs have the ability to start the development of system software along with the hardware, which makes them suitable for use in embedded systems development. The concurrent development of hardware and software enables the simulations of system performance at a very early phase. It allows multiple system partitioning trials and iterations before finalizing the final system architecture. What are the tips of FPGA design? Intelligent design of the FPGA interface is an imperative when using FPGA devices to meet leading-edge system interface requirements such as DDR3. An FPGA interface design without PCB process integration or PCB routing consideration can lead to increased PCB costs and extended design times. The key, as this article demonstrates, is to consider connectivity as the foundation for a FPGA/PCB co-design process and the critical elements that are required for an effective implementation. Connectivity in this context is bidirectional movement of FPGA interface information between the FPGA and PCB domains. Implementing an effective process-connectivity foundation enables the FPGA to be quickly incorporated into the PCB design. An important derivative of a connectivity solution is the repeatable creation of an FPGA interface definition that is optimized for both the FPGA and PCB. The results of this connectivity foundation are lower development costs and improved PCB quality. FPGA proliferationFPGA devices are ubiquitous in new product designs with approximately 100,000 design starts each year. No one argues that there are many benefits offered by FPGA technology. The industry leaders, Xilinx and Altera, both had sales in excess of $1 billion in 2007, with Xilinx approaching $2B. There is a constant stream of new product offerings from the industry leaders that include Xilinx Virtex-5 FXT (high performance processing and I/O) and Virtex-4QV (space applications), Altera's Stratix IV (high density with 13.3 million gates), and Actel’s IGLOO (low power). The diversity of offerings should be a system designer's dream. The FPGA design process is well-defined with a suite of FPGA vendor-provided tools to support it, which includes Xilinx's ISE, Altera's Quartus II, and Actel's Libero IDE. As each new generation of FPGA is delivered, so are the tools that see constant investment. Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/16/2023 13:55
What are the best design practices of high voltage PCB？
When creating a PCB for high voltage DC bias, standards and precautions become much more stringent. High voltage PCB materials and design for arc prevention ensure the final product is safe and functional. Avoid increased costs and danger by keeping these PCB materials and design tips in mind. Are going to search for more information about high voltage PCB layout? If you are curious about high voltage PCB layout, please check and read the content below for more professional knowledge.If you want to order PCB product, please check and custom your order online. What are the features of high voltage PCB? Isolation Slots and cut-outs Most high voltage boards require isolation slots and board cut-outs near any board section, which carries high voltage. In many consumer devices like chargers and power supplies, these slots and board cut-outs are mandatory to pass certain safety standards. These features add an extra layer of safety and would help in high humidity environments and cases where contamination is likely. Isolation slots and cut-outs will usually have to define on a mechanical layer of the board. Board Material Standard FR-4 is not a good material for high voltage boards as it has low dielectric strength. Whenever the cost is not a constraint, it is better to go for a board material with a higher dielectric strength. Some of the high voltage rated materials are: 1.BT Epoxy2.Polyimide3.Isola Board Finishing The most underlooked and important factor when it comes to high voltage PCBs is the board finishing. It mainly includes the surface finish on the pads and any exposed traces. Mainly the finished board should have a smooth finish free of any bumps and should be even along the entire surface. Any imperfections on the high voltage pads like sharp points can result in a high electric field region, which can then cause arcing. What are the best design practices of high voltage PCB？ Time and again, manufacturers receive feedback from PCB users on high voltage boards. This information helps in creating best practices that can reduce the chances of errors in production. RoutingRouting best practices are essential to maintain when designing a high voltage PCB. Ideally, the designer maintains clearance between traces that have a high voltage difference in between. Moreover, it would be best to avoid any sharp edges because they can act as areas of high concentration of electric field. In the internal layers of the board, it’s crucial to avoid running high voltage traces as well. Internal LayersIt’s also vital to make a multi-layer PCB with a medium voltage on each layer. Filling the spaces between the layers requires caution. The thickness of each separation between layers must be .005” in order to maintain a balance in the overall PCB design. In high voltage PCBs, any voids or useless gaps disturb the dielectric value. Polygon PlanesYou should also consider increasing the polygon plane clearance until it touches a safe value in all high voltage PCBs. Internal planes in a multi-layer PCB should have the appropriate separation and a high voltage. This enables the smooth passing of the current without disrupting the other elements on the board. EMIYou may have heard about high voltage PCBs emitting a disturbance on a wide spectrum. To minimize this issue, you can shield the high voltage items after potting with the help of a metal sheet. A small loop area in the ground plane can greatly help in minimizing the disturbances.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/15/2023 15:47
What are the types of environmental testing in PCB?
Environmental testing is about more than just elevated temperature and humidity tests. A series of environmental tests can include shock, vibration, and mechanical tests. These tests should be performed in accordance with the IEC 60068 environmental testing standards. These tests are intended to ensure a new product can survive under when stored or transported at extreme temperatures and humidity, as well as in the operational environment. In this passage, we are providing all the information about environmental testing in PCB manufacturing. If you are going to search environmental testing in PCB, please check and read the content below for more information.If you want to order PCB product, please check and custom your order online. What are the types of environmental testing in PCB? Highly Accelerated TestsAccelerated tests include highly accelerated life test (HALT) and highly accelerated stress screen (HASS). These tests assess product reliability in controlled environments, including high temperature, high humidity, and vibration/shock tests while the device is powered. The goal is to simulate conditions that could lead to the imminent failure of a new product. During testing, the product is monitored in the simulated environment. Environmental testing of electronics normally involves performing tests in a small environmental chamber. Product engineers are sometimes reluctant to accept HALT/HASS results because the stresses placed on the system may be over-spec. In other words, they may exceed those found in the product’s envisioned environment. This has caused many engineers to refuse to fix known problems identified in HALT/HASS tests, only to have these same problems cause product failure later. An experienced CM can often identify simple design and assembly changes that can drastically extend the lifetime of your new product. Humidity and CorrosionMany PCBs will be deployed in a humid environment, thus a common test for PCB reliability is a water absorption test. In this type of test, a PCB is weighed before and after being put in an environmental chamber with controlled humidity. Any water that adsorbs onto the board will increase the board’s weight, and any significant change in weight results in disqualification. When these tests are performed during operation, the exposed conductors should not corrode in a humid environment. When brought up to some potential, copper can easily oxidize, which is why exposed copper is normally plated with an oxidation-resistant alloy. Some examples include ENIG, ENIPIG, HASL, nickel-gold, and nickel. Thermal Shock and CyclingThermal testing is normally performed separately from humidity testing. These tests involve repeatedly changing the board temperature and examining how thermal expansion/contraction affect reliability. In thermal shock testing, the board is rapidly moved between two extreme temperatures using a 2-chamber system. The cold temperature is usually somewhere below freezing, and the high temperature is normally above the glass transition temperature for the substrate (above ~130 °C). Thermal cycling is performed using a single chamber, and the temperature is changed by several from one extreme to the other at 10 °C per minute. In both tests, the board will expand or contract as the board’s temperature changes. During expansion, high stress will be placed on the conductors and solder points, which accelerates the lifetime of the product and allows mechanical failure points to be identified. Why we need environmental testing in PCB manufacturing? Not all PCB assemblies and products require environmental testing, and it is more common in some industries than others. For example, environmental testing of PCB assemblies is a regular requirement for products intended for the military and defence industries. In short, if your product is used in an extreme environment, such as a desert, where the days are very hot and the nights are cold, or at sea, where water-related corrosion and repeated shock are primary risks, your PCB assemblies will need to be tested under these conditions. Does environmental testing affect PCB assemblies? No. The environmental testing process does not have an adverse effect on the appearance or performance of PCB assemblies. Indeed, should you want your circuit boards to look as nice as they possibly can, an expert contract electronics manufacturing partner should be able to offer a cleaning service, or you should be able to make use of your contract manufacturer’s cleaning process. Crucially, it is worth finding out from a prospective contract electronics manufacturer if they perform environmental testing of PCB assemblies on a batch-testing or an all-boards basis. You should only use a partner that performs testing on all of your boards. Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/14/2023 13:48
What are the responsibilities of PCB test technician?
To perform the job successfully, an individual must be able to perform each essential duty satisfactorily. The requirements listed below are representative of the knowledge, skill and/or ability required. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions. Do you know what PCB test technician is? What is the content of PCB test technician job? If you are going to learn more about PCB test technician, please check and read the content below for more.If you want to order PCB product, please check and custom your order online. What is the job content of PCB test technician? A circuit board repair technician repairs printed circuit boards (PCBs) and equipment that utilizes PCB designs. In addition to analyzing the needs of each job and performing necessary maintenance, your duties in this career may include working on the assembly and installation of new printed circuit boards. Your responsibilities also involve restoring full function to circuit boards and other electric control systems. After assessing the repair situation, you may replace circuit board parts or replace the entire board with a new one that has the same specifications as the original. What are the responsibilities of PCB test technician? · Perform routine SMT soldering and desoldering of fine pitch electronic components on Printed Circuit Boards under a microscope.· Inspect PCB Electronic Assemblies for defects; solder quality, parts alignment, missing parts, visual damage, etc· Test PCBs for failures; Repair / Rework defects· Assist in building and testing products the team designs· Ensure laboratory readiness in support of all product development activities· Manage inventory and replenishment of laboratory supplies· Perform system integration and validation testing activities, including verification of interoperability· Measurement data collection and reporting for products in development· Provide support for the product at customer sites and manufacturing locations How to be a circuit board test technician? There are many paths that test technicians have taken to learn the skills of their job, but in general, you can expect a mixture of the following: EducationMost new technicians will have an associate’s degree in electronics or similar training through a technical school. However, some test technicians have learned their skills through several years of experience in a job instead of earning a degree. Typically any sort of electronics or related education is a plus for new test technicians. Training and certificationsTraining by industry standard organizations, such as certification in soldering by IPC, is also considered a plus. Skills and experienceHere are some of the skills and experiences that potential employers will be looking for: · Proficiency at reading and understanding schematics and other electronic engineering documentation· Computer abilities for recording test data and preparing reports· Basic soldering and rework skills· General experience in PCB assembly and electronics manufacturing· Able to work with sales and engineering to satisfy customer requirements· Experience in preparing and setting up different test equipment· Proficiency at operating ICT, flying probe, and other test equipment as required· Test technicians with the training, skills, and experiences that we’ve just looked at will be well-positioned for work in the electronics manufacturing industry. We’ll look at a manufacturer that is looking for people with these skills next.Wanna know PCB knowledge? Check and read for more.
PCB Knowledge ⋅ 08/11/2023 17:17
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