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IntroductionA printed circuit board (PCB) mechanically supports and electrically connects electrical or electronic components using conductive tracks, pads and other features etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate. A PCB allows signals and power to be routed between physical devices.What are PCBs? How Do PCBs Work?CatalogIntroductionⅠ PCB Basics1.1 PCB MaterialsⅡ PCB Product CharacteristicsⅢ Common Sense of PCB ProcessⅠ PCB Basics1.1 PCB Materialsa. Copper Clad Laminate（referred to as CCL, or sheet material）Tg: Glass Transition Temperature, which is the temperature at which glassy substances are transformed between glassy and highly elastic (usually softened). In the PCB industry, this glassy substance is generally referred to as resin or dielectric layer composed of resin and glass fiber cloth. Tg is an important technical index reflecting the heat resistance of printed circuit board substrates. Generally, the higher the Tg value of printed circuit boards, the better the heat resistance. The Tg of general FR-4 copper-clad epoxy glass laminates for SMT printed circuit boards is 130 ～ 140℃, which can meet the requirements when using Sn-Pn solder. For lead-free solders with higher melting points, the Tg of the substrate can not withstand the high temperature of welding if the Tg ≤ 150 ° C. In special cases (high temperature use), the Tg can be greater than 170 ° C. However, excessive Tg will cause the hardness of the substrate to increase and the material to become brittle. Therefore, we cannot simply pursue high Tg. We should comprehensively consider the performance of the board and choose a suitable printed board substrate with a higher Tg, which is one of the requirements for lead-free welding.CTI: Comparative Tracking lndex (or comparative leakage index, tracking index). The highest voltage value that the surface of the material can withstand 50 drops of electrolyte (0.1% ammonium chloride aqueous solution) without the formation of leakage traces. The unit is V.CTE: Coefficient of thermal expansion. Generally, the sheet material performance of a PCB is measured by the linear expansion coefficient, which is defined as the ratio of the increase in length to the original length under a unit temperature change, such as Z-CTE. The lower the CTE value, the better the dimensional stability and vice versa.TD: Thermal decomposition temperature refers to the temperature at which the base material resin loses weight by 5%. It is a sign of delamination and performance degradation caused by the heat of the base material of printed circuit boards.CAF: Conductive Anodic Filament of printed boards is the phenomenon of electrochemical insulation damage on insulating substrates. It refers to the state where dendritic metals are precipitated between wires under the action of an electric field after a voltage is applied to parallel circuits on printed circuit boards. Or conductive anodic filament(CAF) occurs along the glass fiber surface of the substrate, thereby reducing the insulation between the wires.T288: It is a technical index that reflects the welding resistance of the printed circuit board substrate. It refers to the maximum time that the printed circuit board substrate can withstand the high temperature of welding at 288°C without blistering and delamination. The longer this time, the better it is for welding. For traditional Sn-Pb alloys with low welding temperature (220 ～ 230℃), when the thermal decomposition time of printed circuit board substrate is 260 ℃, T260≥30s can meet the requirements of SMT printed circuit board. For lead-free welding, the temperature is generally 250 ~ 260℃, the thermal decomposition temperature of the substrate of the printed circuit board will increase, and only T288≥300s at 288 ℃ can ensure that the substrate does not decompose and the performance is not damaged during welding.DK: dielectric constant.DF: Dissipation factor refers to the ratio of the energy that has been lost in the insulation sheet material of the signal line to the energy that still exists in the line.OZ: oz is the abbreviation of the symbol ounce, which is British measurement unit and also unit of weight. 1 OZ means the thickness of copper with a weight of 1 OZ evenly spread over an area of 1 square foot (FT2). It is the average thickness of copper foil expressed by the weight per unit area. It is expressed by a formula, that is, 1OZ = 28.35g / FT2. b. Copper FoilED Copper Foil: Electrodeposited copper, copper foil commonly used in PCB, cheap.RA Copper Foil: Rolled annealed copper, copper foil commonly used in FPC.Drum Side: smooth side of electrodeposited copper foilMatt Side: rough side of electrodeposited copper foilCopper: Elemental symbol Cu, atomic weight 63.5, density 8.89 g / cm3, and the electrochemical equivalent of Cu2 + is 1.186 g / Ah. c. Prepreg: referred to as PPEpoxy Resin: an organic polymer compound containing two or more epoxy groups in the resin molecule, which is a resin component used in prepregs that are currently commonly used.DICY: Dicyandiamide, a common hardenerR.C: resin contentR.F: resin flowG.T: gel timeV.C: volatile contentHarden: Under certain conditions (high temperature, high pressure or light), the epoxy resin and the hardener undergo cross-linking polymerization to form a polymer with a three-dimensional mesh structure. d. InkViscosity: Viscosity refers to the relative movement between adjacent fluid layers when fluid is flowing, and frictional resistance will be generated between the two fluid layers. Unit: Pascal. Seconds (pa.s).Hardness: The hardness of the ink after pre-baking is 2B, the hardness of the ink after exposure is 2H, and the hardness of the ink after finishing is 6H. Thixotropic: a property that the ink is gelatinous when it is left to stand, but its viscosity changes when it is touched. It is a physical property of a liquid, that is, its viscosity decreases under agitation, and it will return to its original viscosity soon after standing. By stirring, the thixotropic effect lasts for a long time and it is enough to reconstitute its internal structure. To achieve high-quality screen printing, the thixotropic of the ink is very important. In particular, during the squeegee process, the ink is agitated to make it liquid. This action speeds up the speed of ink passing through the mesh, and promotes the original ink with separate wires to be evenly integrated. Once the squeegee stops moving, the ink returns to a stationary state, and its viscosity quickly returns to the original required data. e. Dry Film· Structure of dry film Figure 1. Structure of Dry Film· Dry film consists of three parts and ingredients:   — Supporting film(Polyester)   — Photo-resist dry film   — Covering film(Polyethylene)· Main ingredients① Binder(film-forming resin) ②Monomer ③Photo-initiator ④Plasticiser ⑤Adhesion promoter ⑥Thermal polymerization inhibitor ⑦Dye ⑧Solvent· The types of dry film are divided into three types according to the different methods of developing and removing the dry film: solvent-based dry film, water-soluble dry film, and peel-off dry film; according to the purpose of dry film, it is divided into: dry resist film, masking dry film and solder mask dry film.· Photosensitivity: It refers to the amount of light energy required for the photoresist to react to form a polymer with a certain resistance under the irradiation of ultraviolet light. In the case of constant light source intensity and light distance, the sensing speed is expressed as the length of exposure time. Short exposure time means that the sensing speed is fast.· Resolution: refers to the number of lines (or intervals) that can be formed by the dry film resist within a distance of 1mm. The resolution can also be expressed by the absolute size of the lines (or intervals). f. Net YarnNet density:— T number mesh number: refers to the number of meshes within 1 cm. g. Drill bit· geometry structure name of drill bitFigure 2. Geometry Structure Name of Drill Bit· Point AngleThe point angle is composed of two narrow and long first point angle surfaces and two triangular hook-shaped second point angle surfaces. These four sides meet at the point angle, forming two short edges called chisel edges at the center of the joint. This is the place that the sheet material first touches. This chisel edge is first positioned under pressure and rotation to drill into the stack. A protruding square strip on each of the two outer sides of the first point angle surface is called a margin. This margin tends to spiral upward along with the drill body part, which is the contact part between the drill pin and the hole wall. The right angle at the intersection of the margin and the edge lip is very important to the quality of the hole wall. The point angle has a long edge between the first and second point angle surfaces. The point where the two long edges and the two chisel edges meet in the middle is the point angle. The angle formed by the two long edges is called the point angle. When the drilling paper is made of phenolic resin substrate, the drill point angle is about 90° ~ 110° due to less resistance. When drilling paper is FR4 glass fiber board, the point angle should be slightly blunt at 115° ~ 135°. The most common one is 130°. The angle between the first point angle surface and the horizontal plane of the long edge is about 15°, which is called primary face angle. The second point angle is about 30°, and the angle formed by the chisel edge and the edge lip is called a cheisel edge angle. · Types of drill bitFigure 3. Types of Drill Bit Ⅱ PCB Product Characteristics1) Impedance· The sum of resistance and reactance (capacitance, inductive reactance) on a vector. Common impedance types are characteristic impedance and differential impedance.2) Warpage· Maximum bow (Figure a) and twist (Figure b) of printed circuit boards using surface mount components should be less than or equal to 0.75%3) RoHSRoHS, the abbreviation of restriction of hazardous substances, is the restriction of the use of certain hazardous substances in electrical and electronic equipment. RoHS lists a total of six harmful substances, including: lead(Pb), cadmium(Cd), mercury(Hg), hexavalent chromium( Cr6+), polybrominated diphenyl ether(PBDE), polybrominated biphenyl(PBB).4) BacklightIt is an enlarged visual inspection method to check the integrity of the copper wall of the through hole. The method is to carefully thin the substrate outside the hole wall from a certain direction, and then use the principle of resin translucency to shoot light from the back. If the quality of the chemical copper hole wall is intact and there is no any holes or pinholes, the copper layer must be able to block light and be dark in the microscope. Once there are holes in the copper wall, light spots must appear and be observed , and can be enlarged as photographic evidence. The ground sample is about 4-6mm wide.Figure 5. Backlight Standard Diageam5) Anode Phosphor Copper Ball· Purity requirementsElementContent(%)ElementContent(%)Cu≥99.91Ni≤0.002P0.040-0.06Sb≤0.002Pb≤0.002As≤0.002Fe≤0.0025S≤0.002Sn≤0.002O≤0.002 · Features— A black (or brown-black) film forms on the surface of phosphor copper after power is applied.— Black (or brown-black) film is Cu3P, also called phosphor copper anode film.· Role of phosphor copper anode film— The anode film itself can catalyze and accelerate the (Cu+-E → Cu2+) reaction, thereby reducing the accumulation of CU+.— After the anode film is formed, it can inhibit the continuous generation of Cu+.— The electrical conductivity of the anode film is 1.5X104-1 cm-1, which has metal conductivity.— Phosphor copper is less anodized than pure copper (1A / DM2 P0.04-0.065%, phosphor copper is less anodized than oxygen-free copper, 50MV-80MV) and will not cause anode passivation.— Anode film will greatly reduce the phenomenon of tiny grains falling off the anode.— Anode film prevents the copper anode from dissolving too quickly.6) Method for Estimating Surface Area of Electroplated Copper Anode· Method for estimating surface area of round titanium basket copper anode: pDLF/2p = 3.14 D = diameter of titanium basket L = length of titanium basket F = factor· Method for estimating surface area of square titanium basket copper anode: 1.33LWFL = length of titanium basket W = width of titanium basket F = factor· F is related to the diameter of the copper ball:Diameter = 12 mm    F = 2.2Diameter = 15 mm    F = 2.0 Diameter = 25 mm    F = 1.7Diameter = 28 mm    F = 1.6 Diameter = 38 mm    F = 1.27) ICD IssuesInternal Connection Defects Ⅲ Common Sense of PCB Processa. Etching FactorThe index used to consider the amount of etching lateral erosion, because the amount of lateral erosion will be different for different copper thickness, so the etching factor is different from the total copper thickness.Calculation method:b. Lateral ErosionThe etching of the side wall of the wire under the resist pattern is called lateral erosion, and the degree of lateral erosion is expressed by the width of the side etching:· lateral erosion is related to the type, composition and etching process and equipment of the etching solution. c. Pool EffectDuring the etching process, the circuit board passes through the etching machine horizontally. Due to the gravity acting on it, the fresh medicine is blocked by the old one and cannot effectively react with the copper surface. d. Different Stages of ResinsA-stage resin: Some thermosetting resins are liquid in the early stages of manufacture or liquid when heated, and can still dissolve in some liquids at this time.B-stage resin: Some thermosetting resins can soften when heated in the middle stage of the reaction, but they cannot be completely dissolved or melted. At this time, they can swell or partially dissolve when contacted with some solvents.C-stage resin: The later stage of the reaction of some thermosetting resins, when it is practically insoluble or infusible. e. Font Color of SubstrateRed font: flame retardant grade, other fonts: non flame retardant grade. f. OthersMSDS: Material Safety Data Sheet provides a variety of information on safety, health and environmental protection for chemical substances and products, and can provide information on basic knowledge, protective measures and emergency actions of chemicals. In some countries, MSDS is also called SDS, and SDS terminology is used in ISO 11014.SGS: Societe Generale de Surveillance S.A. Founded in 1887, it is currently the world's largest and oldest non-governmental third party engaged in product quality control and technical certification of multinational companies. Headquartered in Geneva, it has 251 branches around the world, 256 professional laboratories and 27,000 professional and technical personnel, and carries out product quality inspection, monitoring and assurance activities in 142 countries.UL: UNDER WRITERS LABORATORIES INCIPC: The Institute for International and Packaging Electronic CircuitsISO: International Standards OrganizationMIL: Military StandardJPC: Japan Printed Circuit AssociationCOV: Coefficient of variationFR4: Abbreviation for Flame Retardant Type 4. It is the name of a flame-resistant printed circuit board material composed of a composite material of glass fiber and epoxy resin. It is the most widely used printed circuit board. g. pH ValueAlso known as the hydrogen ion concentration index and pH value, it is a scale of the hydrogen ion activity in a solution, which is a measure of the acidity and alkalinity of a solution in the usual sense. The concept was proposed by Danish biochemist Søren Peter Lauritz Sørensen in 1909. P stands for German Potenz, which means strength or concentration, and H stands for hydrogen ion (H +). Sometimes pH is also written in Latin as pondus hydrogenii.Under normal conditions (25°C, about 298K), when pH <7, the solution is acidic, when pH> 7, the solution is alkaline, and when pH = 7, the solution is neutral. h. Hull Cell TestHull designed Hull cell in 1939. The Hull cell test only requires a small amount of plating solution. After a short time test, the plating effect of the plating solution can be obtained in a wide range of current density. Because this test is sensitive to the composition and operating conditions of the plating solution, it is commonly used to determine the concentration and pH value of each component of the plating solution, and to determine the current density range for obtaining a good coating. The Hull cell has become an indispensable tool for electroplating research and electroplating process control.Hull cells are usually made of insulating materials such as plexiglass or rigid polyvinyl chloride. The bottom surface is trapezoidal, and the cathode and anode are placed on two sides that are not parallel. There are five types of capacity: 250ml, 267ml, 320ml, 534ml, and 1000ml. Generally, 250ml plating solution is often added to a 267ml test cell, which is convenient for converting the additives into how many grams per liter.Figure 8. Dimensions of Hull Celli. Current Density A / dm2A/dm2 — how many amperes per square decimeter area, 1A / dm2 — This is the current density of electroplating, which means that the current passes through the plating area of the workpiece per square decimeter is 1A and dm means decimeter. Generally, we use a 267ml Hull cell, place the test piece at the cathode and immerse it in the test solution. The area of the test piece is approximately 1dm2. j. TP: THROUGH POWERCalculation method:k. Replacement ReactionA replacement reaction is a chemical reaction in which a simple substance reacts with a compound to form another simple substance and a compound. Any replacement reaction is a metathesis reaction, including a reaction of metal and metal salt, the reaction of metal and acid, etc.; the replacement reaction must be a redox reaction, and the redox reaction is not necessarily a replacement reaction; the replacement reaction occurs according to the active list of metals. l. EDS：Energy Dispersive X-ray SpectroscopyThe surface of the sample being tested is irradiated with a condensed electron beam. Due to the interaction between the electron beam and the sample, various electrons or X-rays, photons, and other information are generated. Then, this information is collected and processed in different ways to display various characteristics of the sample (morphology, microstructure, composition, crystal plane, etc.) m. SEM：Scanning Electron MicroscopeAn electron beam with a diameter of 20 mm to 30 mm emitted from the cathode of the electron gun is accelerated by the voltage between the cathode and the anode, and is directed toward the lens barrel, and is condensed by the condenser lens and the objective lens, and is reduced into an electron probe with a diameter of about several nanometers. Under the action of the scanning coil on the upper part of the objective lens, the electron probe scans the surface of the sample in a raster pattern and excites a variety of electronic signals. These electronic signals are detected by corresponding detectors, amplified, converted into voltage signals, and finally sent to the grid of the picture tube and modulate the brightness of the picture tube. The electron beam in the picture tube is also raster scanned on the phosphor screen, and this scanning movement is strictly synchronized with the scanning movement of the electron beam on the sample surface, so that a scanning electron image corresponding to the contrast and the intensity of the received signal is obtained. The image reflects the topographical features of the sample surface. n. BONDINGBonding is a wiring method in the chip production process. It is generally used to connect the chip's internal circuit with gold or aluminum wires to the package pins or gold-plated copper foil on the circuit board before packaging. Ultrasonic waves from an ultrasonic generator (generally 40-140KHz), which generates high-frequency vibration through the transducer, are transmitted to the splitter through the horn. When the splitter is in contact with the lead wire and the welded part, under the action of pressure and vibration, the surfaces of the metal to be welded rub against each other, the oxide film is destroyed, and plastic deformation occurs, causing the two pure metal surfaces to closely contact each other to achieve the combination of atomic distance, and finally form a strong mechanical connection. After bonding (ie, after the circuit is connected to the pins), the chip is packaged with black glue. o. The Giovanni EffectIt means that due to the potential difference between two metals, an electric current is generated through the medium, and then an electrochemical reaction occurs, and the anode with a high potential is oxidized. p. Vacuum Degree; Degree of VacuumThe degree of thinness of the gas under vacuum is usually expressed by "high vacuum" and "low vacuum", high vacuum indicates "good" vacuum, and low vacuum indicates "poor" vacuum. If the pressure in the device under test is lower than atmospheric pressure, a vacuum gauge is required for pressure measurement. The value read from the vacuum gauge is called the degree of vacuum. The degree of vacuum is a value indicating that the actual value of the system pressure is lower than the atmospheric pressure, that is: the degree of vacuum = atmospheric pressure-absolute pressureThere are usually two ways to identify the degree of vacuum:   — First, it is marked with "absolute pressure" and "absolute vacuum degree" (that is, how much pressure is higher than "theoretical vacuum"); in actual cases, the absolute pressure value of the vacuum pump is between 0 and 101.325KPa. The absolute pressure value needs to be measured with an absolute pressure meter. The initial value of the gauge (absolute vacuum gauge) for measuring the vacuum degree at 20°C and the place where the altitude = 0 is 101.325KPa (ie, a standard atmospheric pressure).   — The second is to use "relative pressure" and "relative vacuum degree" (that is, how much pressure is lower than "atmospheric pressure") to identify. "Relative vacuum degree" refers to the difference between the pressure of the measured object and the atmospheric pressure at the measurement site and is measured with an ordinary vacuum gauge. In the absence of vacuum (that is, at atmospheric pressure), the initial value of the gauge is 0. When measuring vacuum, its value is between 0 and -101.325KPa (usually expressed as a negative number).Commonly used vacuum units are Pa, Kpa, Mpa, atmospheric pressure, kilogram (Kgf / cm2), mmHg, mbar, bar, PSI, etc. The approximate conversion relationship is as follows:   — 1MPa = 1000KPa   — 1KPa = 1000Pa   — 1 atmospheric pressure = 100KPa = 0.1MPa   — 1 atmospheric pressure = 1 kg (Kgf / cm2) = 760mmHg   — 1 atmospheric pressure = 14.5 PSI   — 1KPa = 10mbar   — 1bar = 1000mbar Frequently Asked Questions about PCB Basic1. What is PCB and types of PCB?A printed circuit board (PCB) is a thin board made from fiberglass, composite epoxy, or other laminate materials. PCBs are found in various electrical and electronic components such as beepers, radios, radars, computer systems, etc. Different types of PCBs are used based on the applications. 2. What is the basis of PCB?PCB is the acronym of Printed Circuit Board, a mechanical base that contains tracks and footprints reflecting the schematic of the design. Modern PCBs are typically made of a non-conductive substrate that is overlayed by copper layers. 3. What are the basic steps of PCB design?Here's the full list of PCB layout and design steps:Create the Schematic.Create a Blank PCB Layout.Schematic Capture: Linking to Your PCB.Designing Your PCB Stackup.Defining Design Rules and DFM Requirements.Place Components.Insert Drill Holes.Route Traces. 4. What are the common types of PCB?Common Types of Printed Circuit BoardsSingle Layer PCB. Single layer printed circuit boards are among some of the simplest to design and manufacture. ...Double Layer PCB.Multi-Layer PCB.High Density Interconnect (HDI) PCB.High Frequency PCB. 5. Which material is used in PCB?copper circuitryPrinted circuit boards (PCBs) are usually a flat laminated composite made from non-conductive substrate materials with layers of copper circuitry buried internally or on the external surfaces. They can be as simple as one or two layers of copper, or in high density applications they can have fifty layers or more.

  A printed circuit board, also known as PCB, is the electrical connection provider of electronic components. It has been developed for more than 100 years; its key point is about layout design. The main advantage of using circuit board is to greatly reduce wiring and assembly errors, improve the level of automation and productivity.   In today's blog, we are going to introduce PCB systematically to show you what is PCB, what's its features, and its manufacturing method and wiring technique and so many more.     Catalog   PCB Introduction PCB Form PCB Features PCB Advantages PCB Basic Manufacturing How to Designing Your Own PCBs PCB Function Testing PCB Design PCB Wiring How Does PCB Works PCB Recycle FAQ PCB Introduction   A printed circuit board, also known as PCB, is the electrical connection provider of electronic components. It has been developed for more than 100 years; its key point is about layout design. The main advantage of using circuit board is to greatly reduce wiring and assembly errors, improve the level of automation and productivity.   Since printed circuit boards are not general end products, there is a slight confusion in the definition of it. For example, the motherboard for personal computers is called the motherboard and cannot be called the circuit board directly, although there is a circuit board in the motherboard. They are not the same, so the relationship between the two cannot be said to be the same when evaluating the industry.   Another example: because integrated circuit parts are mounted on a circuit board, the news media call it IC board, but in essence, it is not equal to a printed circuit board. We commonly refer to PCB as a bare board which components are not on it.   The number of PCB layers can be divided into a single panel, double panel, four-layer board, six-layer board and multilayer board.   PCB Material Common materials of PCB boards are electric boards, glass fiberboards, and various types of plastic boards. PCB manufacturers generally use an insulating portion consists of glass fibre, non-fabric, and resin, then pressed with epoxy resin and copper foil to form a prepreg.   PCB Metallic Coating The metal coating is where the substrate line meets the electronic component. Furthermore, metal solderability, contact, resistance, and so on will have a direct impact on the component's effectiveness. And different metals have a direct impact on production costs.   Copper, tin (the thickness is usually 5 to 15 m), lead-tin alloy (or tin-copper alloy, that is solder, the thickness is 5 to 25 m, about 63 percent is tin), gold (usually plated on the interface), and silver are the most commonly used metallic coatings (usually plated on the interface, or as a whole is silver alloy).   PCB Line Design Software Simple layout design can be completed by hand, but complex circuit design is usually realized through computer-aided design (CAD), and well-known design software includes CAD, Pads (that is PowerPCB), Altium designer (that is Protel), FreePCB, CAM350, and others.   PCB Form   The current circuit boards are primarily made up of the following components:   The Line and Pattern: A line is a tool used to connect the original parts. The large copper surface will be designed as the grounding and power supply layer in the design. The wiring route is created concurrently with the pattern.   Dielectric is used to keep lines and layers insulated.   Through-hole / via: it can switch the lines above the two layers on and off, larger ones are used to set components, and non-through holes (nPTH) are typically used as surface mounting positioning and fixing screws for assembly.   Solder resistant / Solder Mask: not all copper surfaces needed solder parts with sin, so the non-tin soldering area will print something to separate tin (usually epoxy resin), to avoid a short circuit. According to different processes, this can be divided into green oil, red oil and blue oil to distinguish different functional areas.   Legend / Marking/ Silk screen: it is not necessary. Its main function is to mark the name and position of each part on the circuit board for easy maintenance and identification after assembly.   Surface Finish: because the copper surface is easy to oxidize in the general environment, leading to failure to solder tin ( or solder poor), therefore, it will make the copper surface protection which needing to solder sin. The methods of protection include HASL, ENIG, Immersion Silver, tin, Immersion Tin, and OSP, which are generally called surface treatment, having their own advantages and disadvantages.   PCB Features   Bare panels (no parts on them) are also known as "Printed Wiring Board (PWB)". The board itself is made of insulating, non-bending material. The thin wire material that can be seen on the surface is copper foil, which is originally covered on the whole board but is etched away in the manufacturing process, and the remaining part becomes a small net line. These lines are called conductor pattern or wiring and are used to provide electrical connections to parts on the PCB.   The colour of PCB is usually green or brown, which is the colour of the solder mask. It is an insulating protective layer that protects copper wire, prevents short circuit caused by wave welding, and saves solder consumption. Also, a silkscreen will be printed on the solder mask layer. Text and symbols (most are white) are usually printed on them to indicate the location of each part on the board. Silkscreen is also called a legend.   Integrated circuits, transistors, diodes, passive components (such as resistors, capacitors, connectors, etc.) and a variety of other electronic components are installed when the final product made. By connecting wires, electronic signals can be connected and their functions can be work.   PCB Advantages   (1) Because of the reproducibility and consistency of the graphics, the errors in wiring and assembly are reduced, and the maintenance, debugging and checking the time of the equipment are saved;   (2) The design can be standardized and interchangeable;   (3) High density of wiring, small size, lightweight, which is beneficial to the miniaturization of electronic equipment;   (4) It is beneficial to mechanization and automatic production, increasing labour productivity and reducing the cost of electronic equipment     PCB Basic Manufacturing   PCB manufacturing methods are classified into two types: subtractive and additive. At the moment, the subtractive etching copper foil method is primarily used in mass industrial production.   Basic Manufacturing Procedure: First, we’ll need a blank circuit board (a circuit board with complete metal foil), and the rest are required circuit boards.   Screen printing: a screen mask is made from a pre-designed circuit diagram. The screen's unnecessary circuit is covered with wax or waterproof material. Following that, the screen mask is placed on a blank circuit board, with a protective agent applied to the screen to prevent corrosion. Finally, immerse the circuit board in the corrosion solution; the part not covered by the protective agent will be corroded away, leaving only the rest to be cleaned away.   Photosensitive board: a pre-designed circuit diagram is printed on a transparent film mask (the simplest method is to print the film with a printer), and the required part is printed in an opaque color in the same way. Then, apply photosensitive pigment to the blank circuit board, place the prepared film mask on the board while it is blazing for a few minutes, remove the mask, and use a developer to display the pattern on the board.   Engraving: use a milling machine or laser engraving machine to remove unnecessary parts of a blank line directly.   Other Manufacture Procedure:   （1）Additive The additive, is a pre-coated copper substrate coated with a photoresistor (D/F), exposed to ultraviolet light and exposed where it is needed. Then using electroplating to thicken the copper of the formal circuit line to the required specification, and plating a layer of anti-corrosion thin tin, and finally remove the photoresist (this process is called film removal), and then etch the copper foil layer under the photoresist.   （2）Layer Method The lamination method is one of the methods of making multilayer printed circuit board. The outer layer is made after the inner layer is wrapped, and the outer layer is treated by the subtractive or additive method. The sequential layer method can be used to get the multi-layer printed circuit board with multiple layers by repeating the action of the stacking method. 1. Making inner layer 2. Laminated formation( bonding different layers) 3. Layer completion ( Outer metal-containing foil film by subtractive method, mixing with the additive method) 4. Drilling   （3）Panel Method 1. Whole PCB electroplating 2. Add a barrier layer where the surface is to be retained 3. Etching4. Removal of barrier layer   （4）Pattern Method 1. Add a barrier layer to the area where the surface is not required 2. Electroplating requires with thickness 3. Removal of barrier layer4. Etching into unnecessary foil film to disappear   （5）Complete Addition Method 1. Add a barrier layer where there is no conductor 2. Circuit consisting of no electrolytic copper   （6）Partial Addition Method 1. Covered with electrolytic copper PCB 2. Add a barrier layer where there is no conductor 3. Electrolytic copper plating 4. Removal of barrier layer 5. No electrolytic copper disappeared until etched under the original barrier layer.   （7）ALIVH ALIVH (Any Layer Interstitial Via Hole，Any Layer IVA), this is using aramid fiber fabric as the substrate. 1. Prepreg: dip the fabric in an epoxy resin to form a “Adhesive sheet”. 2. Laser drilling. 3. Filling the hole with conductive paste. 4. Attaching copper foil to the outer layer. 5. Making Circuit pattern by etching on copper foi. 6. Gluing the copper foil on the semi-finished product after the second step. 7. Laminated formation 8. Repeating steps 5 to 7 until completed.   （8）B2it (Buried Bump Interconnection Technology) 1. First make a double panel or multilayer board. 2. Printing silver paste as cone on copper foil. 3. To place the adhesive on a silver paste, making silver cone to penetrate the adhesive. 4. Attaching the previous adhesive to the board of the first step. 5. Etching the copper foil of the adhesive into a circuit pattern. 6. Repeat the second to fourth steps until it completed.   How to Designing Your Own PCBs   How do you go about designing your own PCB? The ins and outs of PCB design are way too in-depth to get into here, but if you really want to get started, here are some pointers:   1. Find a CAD package: there are a lot of low-cost or free options out there on the market for PCB design. Things to consider when choosing a package:   Community support: are there a lot of people using the package? The more people using it, the more likely you are to find ready-made libraries with the parts you need.   Ease-of-use: if it's painful to use it, you won't.   Capability: some programs place limitations on your design- number of layers, number of components, size of the board, etc. Most of them allow you to pay for a license to upgrade their capability.   Portability: some free programs do not allow you to export or convert your designs, locking you into one supplier only. Maybe that’s a fair price to pay for convenience and price, maybe not.   2. Look at other people’s layouts to see what they have done. Open Source Hardware makes this easier than ever.   3. More practice.   4. Maintain low expectations. Your first board design will have lots of problems. Your 20th board design will have fewer, but will still have some. You’ll never get rid of them all.   5. Schematics are important. Trying to design a board without a good schematic in place first is an exercise in futility.   Finally, a few words on the utility of designing your own circuit boards. If you plan on making more than one or two of a given project, the payback on designing a board is pretty good- point-to-point wiring circuits on a protoboard is a hassle, and they tend to be less robust than purpose-designed boards.   PCB Function Testing   More intensive PCB, with the higher bus speed and analog RF circuits, pose unprecedented challenges to the testing, where efficient testing requires careful design, thoughtful testing methods and appropriate tools which can provide credible test results.   In high-density UUT, if calibration or diagnosis is required, manual work is likely to be required. This is because the machine is limited and the test requires faster (the UUT can collect data quickly with a probe instead of feedback the information to the edge connector), in this case, that the operator is required to probe the test points on the UUT to make sure the test points are clearly marked.   Testing Issues include: （1） Is the probe bigger than the test point? （2）Is the probe in danger of shorting several test points and damaging UUT? （3） Is there a shock hazard to the operator? （4）Can each operator find out the test point quickly and check it out? （5）Are test points large and easy to identify? （6）How long does it take the operator to press the probe on the test point to get an accurate reading? （7）If the time is too long, there will be some trouble in the small test area, for example, the operator's hand will slide, so it is recommended to expand the test area to avoid this problem.   After considering the above problems, the test engineer should re-evaluate the type of the test probe, modify the test file to better identify the location of the test point or even change the requirements for the operator.   PCB Automatic Exploration In some cases, the use of automated probes may be required, such as when PCB is difficult to detect manually, or when the test speed is significantly reduced due to the technical limitations of the operator, under this case which an automated approach should be considered.   The automatic probe can eliminate human error, reduce the possibility of short circuit at several test points, and speed up test operation. However, it should be noted that there may be some limitations to automated probes, depending on the vendor's design, including:   （1）A size of UUT （2）Number of synchronous probes （3）How close are the two test points? （4）Positioning accuracy of the testing probe （5）Can the system detect UUT on both sides? （6）How fast does the probe move to the next test point? （7）What is the actual interval required for the probe system? (it is generally larger than an offline functional test system.)   Automatic detection usually does not touch test points with probe and is generally slower than the production line, so two steps may be required: if the detector is used only for diagnosis, the traditional function test system can be used in the production line, and the detector should be put on the side of the production line as the diagnostic system. If the purpose of the detector is using the UUT to calibrate, it is necessary to use multiple systems, which is still much faster than manual operation.   Another key issue is how to integrate the test system into the production line. Is there still room on the production line? Can the system be connected to the conveyor belt? Fortunately, many new detection systems are compatible with the SMEMA standard, so they work in an online environment.   PCB Boundary Scan Because it requires specialized components to perform the task, this technology should have been discussed prior to the product design phase. Devices with IEEE1194 (boundary-scan) support can be purchased in UUT with a digital circuit, allowing most diagnostic problems to be solved with little or no detection. However, because it expands the area of each compatible device, boundary scanning reduces the overall functionality of the UUT (4 to 5 pins per chip and some wires).   When selecting this technology, the goal is to improve diagnosis. Furthermore, it is emphasized that boundary scans can be used to program Flash memory and PLD devices on UUT, which strengthens the case for selecting the test method.     PCB Design In the design of a printed circuit board, the layout of components and wiring of circuit connection are two key aspects.   PCB Layout The layout is to put the circuit device in the printed circuit board wiring area.   The layout not only affects the wiring work behind it, but it also has a significant impact on the overall performance of the circuit board. To meet the requirements of process, detection, and maintenance, the components should be uniform, neat, and compactly placed on the PCB to minimize the lead and connection between the components, resulting in uniform assembly density.   PCB Functional Differentiation Components should be arranged in groups based on their power-supply voltage, digital and analog circuits, speed, current, and so on, to avoid interference with one another.   When installing the digital circuit and analog circuit on the circuit board, the ground wire and power supply system of the two circuits should be completely separated, and the digital circuit and analog circuit should be arranged in different layers if the conditions allow. When arranging the fast, medium, and low-speed logic circuits on the circuit board, they should be close to the connector, while the memory should be far away from the connector.   This reduces common impedance coupling, radiation, and crosstalk. The clock and high-frequency circuits, which are the primary sources of disturbance emitter, must be arranged separately and away from the sensitive circuit.   PCB Thermal Magnetic Balance The heating parts and the heat-sensitive parts are as far away as possible, the influence of electromagnetic compatibility should be considered.   Manufacturability: (1) Surface The mounting parts are installed on one side as far as possible and simplify the assembly process.   (2) Spacing The minimum distance between components is determined according to the shape of components and other related properties. At present, the distance between components is generally not less than 0.2mm~0.3mm, the distance between components and PCB edge should be more than 2mm.   (3) Direction The direction and density of the elements should be favourable to the convection of the air. Considering the assembly process, the component direction is as consistent as possible.   PCB Wiring   1. Wires (1) Width The minimum width of the printed wire is determined by the adhesive strength between the conductor and the insulating substrate and the current value flowing through them. Printed wire can be as wide as possible, especially power lines and ground wires, as wide as possible under the condition of the plate surface, even if the area is tight, generally not less than 1mm.   In particular, ground wires, even if they are not allowed to be widened locally, it is necessary to widen somewhere permitted to reduce the resistance of the whole ground wire system. For example, the conductors longer than 80mm, even if the current is small, should be widened to reduce the influence of conductor voltage drop on the circuit.   (2) Length To minimize the length of the wiring, the shorter the wiring, the less interference and crosstalk, and the lower the parasitic reactance and the less radiation. Especially the FET gate, transistor base and high-frequency circuit should pay more attention to short wiring.   (3) Gap The distance between adjacent conductors should meet electrical safety standards. The main electrical issues affecting wiring spacing are crosstalk and voltage breakdown. The spacing should be as wide as possible for ease of operation and production, and the minimum spacing should be appropriate to the applied voltage. This voltage includes the operating voltage, the additional fluctuation voltage, the overvoltage, and the peak voltage for other reasons. For safety reasons, the spacing should be wider when there is a current-voltage in the circuit.   (4) Path The signal path from driver to load should be constant in width. The path impedance (resistance, inductance, and capacitance) changes as the path width changes, resulting in reflection and line impedance imbalance. As a result, it is best to keep the path width constant.   Furthermore, it is best to avoid right and sharp angles for the wiring corner, which should generally be greater than 90 °. The inner edge of the right path can generate a concentrated electric field, which produces noise coupled to the adjacent path, and the 45 °path outperforms the right angle and acute angle paths. When two conductors come together at an acute angle, the acute angle should be turned into a circle.   2. Aperture and Pad  The aperture of components should be better matched with the diameter of the lead; in other words, the diameter of the installation hole should be slightly larger 0.150.3mm than the component's lead diameter. DIL packaging pins and most small components have an aperture of 0.8mm and a pad diameter of about 2mm.   For large pad aperture, in order to get better adhesion ability, the ratio of the aperture and the diameter of the pad is about 2 for epoxy glass plate and 2.5~3 for phenol cardboard.   Perforation, which is commonly used in multilayer PCBs, has a minimum available diameter that is related to plate thickness, and the plate thickness to aperture ratio is usually 6:1. A high-speed signal generates 14nH inductance and 0.38pF capacitance when perforated. As a result, when laying high-speed signal channels, the number of holes should be kept to a bare minimum.   If layer changes are unavoidable for high-speed parallel lines (such as address and data lines), it is necessary to ensure that the number of holes in each signal line is the same, and that the number of holes is minimized. When necessary, a printed conductor protection ring or protective line should be installed to prevent oscillations and improve circuit performance.   3. Grounding Design Unreasonable grounding design will affect the printed circuit board, fail to reach the design target, and even can not work. The ground wire is the reference of the potential in the circuit and the common current channel. The ground potential value is zero theoretically, but in fact, because of the existence of conductor impedance, the potential everywhere of the ground wire is not all zero. As long as the ground wire has a certain length, it's potential may not in zero everywhere. The ground wire is not only a necessary common circuit channel, it also a channel for interference.   One point grounding is the basic principle of eliminating grounding interference. The ground wire of all circuits and devices must be connected to a unified grounding point, which is used as the circuit and the zero potential reference point of the equipment. One point grounding is divided into common ground wire series grounding and independent wires parallel grounding.   The common ground-wire series grounding is simple. The grounding lead of each circuit is relatively short, and its resistance is relatively small. This kind of grounding method is often used in the earthing of the equipment cabinet. The independent wires parallel grounding has one ground point which is defined as the ground reference point. The other points that need to be grounded are directly connected to this point, and the earth potential of each circuit is related only to the ground current base impedance of the circuit, which will not be affected by other circuits.   The Following Points Should Be Noted in Specific Wiring: （1）The line length is as short as possible in order to minimize the lead inductance. In low-frequency circuits, multipoint grounding is avoided because the ground current of all circuits flows through a common grounding impedance or grounding plane.   （2）Common ground wires should be arranged as far as possible on the edge of the printed circuit board. As much copper foil as possible should be retained on the circuit board as the ground wire, which can enhance shielding ability.   （3）The double-layer plate can use the ground surface, the purpose of which is to provide a low-impedance ground wire.   （4）In a multi-layer printed circuit board, a grounding layer can be set, and it is designed as a mesh. The spacing of the earth grid can not be too large because one of the main functions of the earth wire is to provide the signal return path. If the spacing of the grid is large signal-loop area will be formed, which will cause radiation and sensitivity problems. In addition, if the signal reflux path is a small loop area, other ground lines will not take into effect.   （5）The earth surface can minimize the radiation loop.   How Does PCB Works PCB Recycle   PCB manufacturing technology is a very complex, comprehensive processing technology. Especially in the process of wet processing, a large amount of water is needed, so there are many kinds of heavy metal wastewater and organic wastewater discharged.    The composition is complex, and the treatment is difficult. If the copper foil utilization ratio of the printed circuit board is 30% and 40%, most of the copper content is in wastewater. If the thickness of each copper foil is 35 microns based on 10, 000 square meters of double panels, the wastewater contains about 4500 kilograms of copper, and there are many other heavy metals and precious metals. These are found in waste liquid and wastewater, if the metal is discharged without treatment, it is not only a big waste but also pollutes the environment.    Therefore, the treatment of wastewater and the recycling of copper and other metals in the process of PCB production are of great significance and are indispensable parts in PCB production.   It is well known that the wastewater in the production of the printed circuit board is a large amount of copper, and a very small amount of lead, tin, gold, silver, fluorine, ammonia, organic compounds and organic complexes, etc.   As for the production of copper wastewater, the main processes are: copper sink, copper plating, copper electroplating, etching and various PCB pretreatment processes (chemical pretreatment, brush plate pretreatment, pozzolanic ash grinding plate pretreatment, etc.).   The copper-containing wastewater produced by the above processes can be divided into complex wastewater and non-complex wastewater according to its composition. In order to make the wastewater treatment meet the environment-protection standard, and the maximum allowable compound concentration of copper is 1mg/l (according to copper), but different wastewater treatment methods must be adopted for different copper-containing wastewater. FAQ   1. What is PCB? A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate.   2. What is PCB and types of PCB? A printed circuit board (PCB) is a thin board made from fiberglass, composite epoxy, or other laminate materials. PCBs are found in various electrical and electronic components such as beepers, radios, radars, computer systems, etc. Different types of PCBs are used based on the applications.   3. What can a PCB be used for? Printed circuit boards (PCBs) are used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate, employed in the manufacturing of business machines and computers, as well as communication ...   4. Why are PCB green? It is due to the solder mask, which protects the copper circuits printed on the fibre glass core to prevent short circuits, soldering errors, etc. ... The colour of the solder mask gives the board its appearance.   5. What is PCB and its advantages? Compact Size and Saving of Wire. A characteristic PCB includes a large number of electronic components. On a Printed circuit board, the interconnection between the components is made through copper tracks instead of using a number of current carrying wires. It makes the interconnections less bulky.   6. How long does it take for PCBs to break down? 3.5 to 83 days. The time it takes for half of the amount of PCBs (initially) present to be broken down ranges from 3.5 to 83 days for molecules with 1 to 5 chlorine atoms. In water, PCBs are essentially broken down by the effect of sunlight (photolysis).   7. What is the disadvantage of PCB? Disadvantages: Easy to Cause Handling Damage. Process Uses a Carcinogen (Thiourea) Exposed Tin on Final Assembly can Corrode.   8. Which PCB design software is the best for beginners? Top Best PCB Design Software of 2021 a. PROTEL (Altium Designer)  b.PADS (PowerPCB)  c. ORCAD.  d. Allegro.  e. Eagle（Easily Applicable Graphical Layout Editor） f. Kicad. g. EasyEda. h. Fritzing.   9. What are the advantage of flexible PCB? The flexible circuit board are designed for saving room and improving the flexibility to meet a smaller and higher density mounting design, it also helps to reduce the assembly process and enhance reliability.   10. Why do we use PCB instead of breadboard circuit? The advantages of a printed circuit board: the board is permanent to have an electronic device worked. PCB has a better current carrying capacity comparing to a breadboard, you can make your traces wider to take more current so that work well. ... You can mount heat-sinks to the board so that have them rigid.

Today in this article we will discuss about how PCB is developed and its industrial trend. Printed circuit board, also called PCB, is an important electronic component and the support of electronic components, which also have a circuit in which a metal conductor can be connected to an electronic component. Nowadays electronic equipment requires high performance, high speed and thin miniaturization. As a multidisciplinary industry, PCB is the key technology of high-end electronic equipment. It plays an important role in electronic interconnection technology. Introduction to how PCB worksCatalogI PCB overviewII. Main types of PCB2.1 Single-sided boards2.2 Double-sided boards2.3 Multi-layer boardsIII Industrial chain of PCB3.1 Glass fiber cloth3.2 Copper foil3.3 Copper clad laminateIV Development of PCB industry in ChinaFAQI PCB overviewTraditional circuit boards are referred to as printed circuit boards because the circuit and its surface are created using the printing etching inhibitor method. At the moment, most circuit boards are made by using an etching inhibitor (film pressing or coating), and then etching is used to make the circuit board after exposure and development.Due to the continuous miniaturization and refinement of electronic products, most of the current circuit boards are coated with etching inhibitors (film pressing or coating). After exposure and development, the board will be etched to form the final circuit board. PCBs have progressed from single-sided to double-sided, multilayer, and flexible boards, and this trend is expected to continue. Because of its ongoing advancements in the areas of high precision, high density, and high reliability. PCB maintains a strong vitality in future electronic equipment development projects due to its continuous development of high precision, high density, and high reliability, reducing volume, cost, and improving performance.Printed circuit boardThe discussion of the development trend of the future PCB manufacturing technology at home and abroad is almost consistent, that is, developing toward the direction of high density, high precision, fine aperture, fine wire, fine spacing, high reliability, multilayer, high speed transmission, light weight and thin shape. At the same time, it is aimed to increase productivity, reduce costs, reduce pollution, adapt to multi-species and small run production during manufacturing. The technical development level of printed circuit is represented by the line width, aperture and the ratio of thickness to aperture of printed circuit.The creator of the printed circuit board was an Austrian called Paul Eisler. In 1936, he first used a printed circuit board in a radio. In 1943, Americans mainly applied this technology to military radios. Then in 1948, this invention was officially approved for commercial use in the United States.  Since the middle of 1950s, printed circuit boards have been widely used.Before the emergence of PCB, the interconnection of electronic components was accomplished by direct connection of electrical wires. Nowadays, wires exist only for laboratory applications. Printed circuit boards (PCB) have definitely occupied the position of absolute control in the electronic industry. II Main types of PCBAccording to the number of circuit layers, it can be divided into single-sided board, double-sided and multilayer board. The common multilayer board is usually 4 or 6 layers, and the complex multilayer board can have dozens of layers. Printed circuit boards are mainly divided into three types:2.1 Single-sided boardsOn the most basic PCB, the parts are concentrated on one side and the wire will be on the other (when there is patch element, it is on the same side as the wire, and the plug-in device is on the other side). Because the wire only appears on one side, this type of PCB is called single-sided board. The single-sided board has many strict restrictions on the design circuit (since there is only one side, the wiring cannot intersect and have to go around a separate path), so only the early circuits use this type of board.2.2 Doublesided boardsThere are wiring on both sides of this kind of circuit board.However, to use these two sides of the wire, you must have an appropriate circuit connection between the two sides. The "bridge" between these circuits is called “via”. The via hole is a small hole filled or coated with metal on the PCB, which can be connected to both sides of the wire. It can be connected to two sides of the wire. Because the area of the double-sided board is twice as large as that of the single panel,  it solves the difficulty of wiring interleaving in the single panel (it can get to the other side through the hole), so it is more suitable for the circuit which is more complicated than the single sided.2.3 Multi-layer boardsIn order to increase the area in which wiring can be made, the multilayer board is made up of more single or double-sided wiring boards. A printed circuit board with one side as the inner layer, two single sides as the outer layer or two sides as the inner layer, and two single sides as the outer layer, which is interlinked with conductive patterns according to the design requirements, is composed of four layers and six layers of printed circuit boards, also known as multilayer printed circuit boards (PCB). The number of layers on the board does not mean that there are several independent wiring layers. In special cases, an empty layer is added to control the thickness of the board, and the number of layers is usually even, and contains the outermost two layers. Most motherboards are 4 to 8 layers, but technically we can do nearly 100 layers of PCB. Large scale supercomputers mostly use quite many layers of motherboards. However, because such computers have been replaced by clusters of many common computers, super multilayer boards have been gradually unused. Because the layers in the PCB are tightly combined, it is generally not easy to see the actual number, but if you look closely at the motherboard, you can see it. Also there are two kind of boards called rigid and flexible printed boards. > Rigid and Flexible Printed BoardsDivided into rigid circuit boards, flexible circuit boards and rigid-flexible printed circuit boards. The PCB shown in the first picture below is generally referred to as the rigid PCB, and the yellow connection line in the second picture is called flexible PCB. The intuitive difference between a rigid PCB and a flexible PCB is that the flexible PCB is flexible. The common thickness of rigid PCB is 0.2mm / 0.4mm / 0.6mm / 0.8mm / 1.0mm / 1.2mm / 1.6mm / 2.0mm etc. The common thickness of flexible PCB is 0.2mm. The thickening layer is added to the back where the parts are to be welded , and the thickness of the thickened layer varies from 0.2 mm to 0.4 mm. TThe purpose of understanding these is to provide them with a spatial reference for the design of a structural engineer. The common materials for rigid PCB include: phenolic paper laminates, epoxy paper laminates, Polyester glass felt laminates, epoxy glass cloth laminates; flexible PCB materials include: polyester film, polyimide film, ethylene propylene fluoride film.Rigid boardFlexible board III Industrial chain of PCBAccording to the upstream and downstream classification of the industrial chain, PCB industry can be divided into raw materials - CCL (copper-clad laminate) - PCB (printed circuit board) - electronic product application. The relationship is simply expressed as: 3.1 Glass fiber clothGlass fiber cloth is one of the raw materials of copper clad plate, which is made of glass fiber yarn and account for about 40% of the cost of copper clad laminate (thick plate) and 25% (thin plate). Glass fiber yarn is calcined into liquid state from raw materials such as silica sand in the kiln, then pulled into very fine glass fiber through extremely small alloy nozzles, and then hundreds of glass fibers are twisted into glass fiber yarn. The manufacture of glass fabric is similar to that of weaving enterprises. It can control production capacity and quality by controlling rotation speed, and the specifications are relatively single and stable. Since World War II, there has been almost no significant change in specifications.Unlike CCL, prices of glass fabrics are the most affected by supply and demand, fluctuating between $0.50-1.00 a meter in recent years. Taiwan and mainland China account for about 70% of the world's production capacity.3.2 Copper foilCopper foil is the raw material that accounts for the largest proportion of the cost of copper clad laminate, about 30% of the cost of copper clad plate (thick plate) and 50% (thin plate). Therefore the price increase of copper foil is the main driving force of the price increase of copper clad laminate. The price of copper foil is closely reflected in the change of copper price. However, the bargaining power is relatively weak. With the rising copper prices, copper foil manufacturers are in a difficult situation, and many enterprises have been forced to close down or be annexed. Even if copper clad laminate manufacturers accept copper foil price increases, copper foil manufacturers are still in a general loss. Another wave of price increases is likely to occur in the first quarter of 2006, possibly driving up CCL prices due to the price gap. 3.3 Copper clad laminateCopper clad laminate (CCL) is a direct raw material of PCB, which uses epoxy resin as fusion agent to press glass fiber cloth and copper foil to make printed circuit board (PCB) after etching, electroplating and multilayer laminate pressing. The copper clad laminate industry is not in high demand for capital, about 3 million to 40 million yuan, and can be stopped or converted at any time. In the upstream and downstream industrial chain structure, CCL has the strongest bargaining power. It has a strong voice in the procurement of glass fiber cloth, copper foil and other raw materials , and as long as the demand of downstream is good, the manufacturer of CCL can transfer the pressure of rising costs to the downstream PCB manufacturers. IV Development of PCB industry in ChinaThe development of PCB in China began in 1956. In 1963-1978, it is gradually expanded to be the PCB industry. More than 20 years after the reform and opening up, due to the introduction of foreign advanced technology and equipment, single-sided board, double-sided board and multi-layer board had a rapid development. The domestic PCB industry has gradually developed from small to large scale.Due to the concentration of downstream industries and relatively low labor and land costs, China has become the region with the strongest development momentum. In 2002, China became the third largest output country of PCB. In 2003, the output value and import and export volume of PCB exceeded $6 billion, which overtaking the United States for the first time and becoming the second largest output country in the world. The proportion of output value also increased from 8.54% in 2000 to 15.30%, nearly doubling. In 2006, China has replaced Japan as the world's largest PCB production base and the most active technology development country. China's PCB industry has maintained a high growth rate of about 20%, which is far higher than that of the global PCB industry. In terms of production composition, the main products of China's PCB industry have shifted from single-sided and dual-sided to multilayer, and are being upgraded from 4-6 layers to more than 6-8 layers. With the rapid growth of multilayer printed board, HDI board and flexible boards, China's PCB industrial structure is gradually being optimized and improved. However, although China's PCB industry has made considerable progress, there is still a big gap compared with advanced countries, and there is still much room for improvement in the future. First of all, China's entry into the PCB industry is relatively late and there are no specialized PCB research and development institution. There is a big gap between the research and development capabilities of some new technologies and foreign manufacturers. Secondly, in terms of product structure, the production of medium and low laminates is still dominated. Although FPC and HDI boards are growing rapidly, the proportion is still low because of its small base. Most of our PCB production equipment depends on imports, and some core raw materials can only rely on imports. The industrial chain is incomplete, which also hindered the domestic PCB series enterprise's development step.  FAQ 1. What is PCB?A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. 2. What is PCB and types of PCB?A printed circuit board (PCB) is a thin board made from fiberglass, composite epoxy, or other laminate materials. PCBs are found in various electrical and electronic components such as beepers, radios, radars, computer systems, etc. Different types of PCBs are used based on the applications. 3. What can a PCB be used for?Printed circuit boards (PCBs) are used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate, employed in the manufacturing of business machines and computers, as well as communication ... 4. Why are PCB green?It is due to the solder mask, which protects the copper circuits printed on the fibre glass core to prevent short circuits, soldering errors, etc. ... The colour of the solder mask gives the board its appearance. 5. What is PCB and its advantages?Compact Size and Saving of Wire. A characteristic PCB includes a large number of electronic components. On a Printed circuit board, the interconnection between the components is made through copper tracks instead of using a number of current carrying wires. It makes the interconnections less bulky. 6. How long does it take for PCBs to break down?3.5 to 83 days. The time it takes for half of the amount of PCBs (initially) present to be broken down ranges from 3.5 to 83 days for molecules with 1 to 5 chlorine atoms. In water, PCBs are essentially broken down by the effect of sunlight (photolysis). 7. What is the disadvantage of PCB?Disadvantages: Easy to Cause Handling Damage. Process Uses a Carcinogen (Thiourea) Exposed Tin on Final Assembly can Corrode. 8. Which PCB design software is the best for beginners?Top Best PCB Design Software of 2021a. PROTEL (Altium Designer) b.PADS (PowerPCB) c. ORCAD. d. Allegro. e. Eagle（Easily Applicable Graphical Layout Editor）f. Kicad.g. EasyEda.h. Fritzing. 9. What are the advantage of flexible PCB?The flexible circuit board are designed for saving room and improving the flexibility to meet a smaller and higher density mounting design, it also helps to reduce the assembly process and enhance reliability. 10. Why do we use PCB instead of breadboard circuit?The advantages of a printed circuit board: the board is permanent to have an electronic device worked. PCB has a better current carrying capacity comparing to a breadboard, you can make your traces wider to take more current so that work well. ... You can mount heat-sinks to the board so that have them rigid. 11. What PCB means?Printed-Circuit-BoardA printed circuit board, or PC board, or PCB, is a non-conductive material with conductive lines printed or etched. Electronic components are mounted on the board and the traces connect the components together to form a working circuit or assembly. 12. Why are PCBs dangerous for humans?PCBs are a probable human carcinogen.Studies of PCBs in humans have found increased rates of melanomas, liver cancer, gall bladder cancer, biliary tract cancer, gastrointestinal tract cancer, and brain cancer, and may be linked to breast cancer. 13. What are PCBs in electronics?A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate. 14. Why are PCB green?It is due to the solder mask, which protects the copper circuits printed on the fibre glass core to prevent short circuits, soldering errors, etc. ... The colour of the solder mask gives the board its appearance. 15. What is PCB and its role?A process control block (PCB) is a data structure used by computer operating systems to store all the information about a process. It is also known as a process descriptor. When a process is created (initialized or installed), the operating system creates a corresponding process control block. 16. Which software is best for PCB design?- NI Multisim.- KiCad EDA.- Autodesk EAGLE.- DipTrace.- Ultiboard.- CAM350.- ExpressPCB Plus.- SolidWorks PCB. 

Every time you want to create a printed circuit board (PCB), you need to design holes, pads, and traces for your circuit. Then you send this design to a manufacturer or etch it yourself. What if you want to create a circuit board by yourself but it sounds hard? Don't worry, there are many free and affordable tools available that will help you do this. There are just a few steps you need to go through, and anyone can do it – even if you have no prior experience.I What is a PCB?According to Wikipedia, a printed circuit board (PCB) mechanically supports and electrically connects electronic components using conductive tracks, pads, and other features etched from copper sheets laminated onto a non-conductive substrate. Components (e.g., capacitors, resistors, or active devices) are generally soldered onto the PCB. Advanced PCBs may contain components embedded in the substrate, and modern designs can include multiple layers (from single-layer to 50+ layers for complex applications).Printed circuit boardWould you like to make your own smart device? Or IoT controller? Or robot? Or drone? Well, then you would want to make a printed circuit board. PCBs are the foundation of virtually all modern electronics!A printed circuit board is typically made from FR-4 (Flame Retardant 4), a composite material made of woven fiberglass cloth with an epoxy resin binder that is flame resistant. While green is the traditional and most common color due to the green solder mask, PCBs now come in various colors including blue, red, black, white, yellow, and even matte black for aesthetic purposes. The solder mask protects the copper traces from oxidation and prevents solder bridges during assembly.On the board, there are components. Initially, the PCB is bare, but you solder the components onto the board following your design. Modern PCBs can use through-hole technology (THT) or surface-mount technology (SMT), with SMT being more common in contemporary designs due to its compact size and automated assembly capabilities.II How to Make a Printed Circuit Board?To make a printed circuit board you need to:1. Design schematics2. Create the PCB layout3. Generate manufacturing files (Gerber files)4. Get the board manufactured and assembled2.1 Design SchematicsThe first and most important step in PCB design is to start with your schematics. This is the blueprint of your circuit that shows how all components connect electrically.Before you start drawing traces and placing components, you need to know what circuit you want to build. You need to find or design schematics for your circuit and choose appropriate PCB design software. Popular options in 2025 include:KiCad - Free, open-source, and very powerfulEasyEDA - Free, web-based with integrated manufacturingAltium Designer - Professional-grade (paid)Eagle (Autodesk) - Popular hobbyist choice with free tierFusion 360 Electronics - Integrated with 3D CAD (paid)CircuitMaker - Free community-driven platform2.2 Create the PCB LayoutStart by drawing your schematic diagram into the software you have chosen. You need to define the connections (nets) between different components.This process involves placing component symbols and connecting them with wires that represent electrical connections. Modern PCB software will check for electrical rule violations (ERC - Electrical Rule Check) to catch errors early.Schematic design exampleNext, you transfer your schematic into a physical PCB layout. This involves:Component placement - Arranging components efficiently on the boardRouting traces - Drawing copper connections between padsPower and ground planes - Creating solid copper areas for power distributionDesign rule checking (DRC) - Ensuring your design meets manufacturing constraintsDrawing PCBs is both technical and artistic. Take your time and follow PCB design best practices:Keep traces as short as possible, especially for high-frequency signalsMaintain proper trace width for current requirements (use trace width calculators)Provide adequate spacing between traces (typically 6-8 mils minimum)Use ground planes to reduce noise and improve signal integrityConsider thermal management for power componentsPlace decoupling capacitors close to IC power pinsPCB layout exampleWill you put the circuit board in an enclosure? Consider the mechanical constraints: tall components might need specific placement, mounting holes must align with your enclosure, and connectors should be accessible. Print out your board design at 1:1 scale to verify physical fit before manufacturing.2.3 Manufacturing Your PCBWhen you finish your layout, it's time to prepare your design for manufacturing. You'll need to generate Gerber files (the industry standard format) and a drill file. Most PCB software can export these automatically.Home Etching vs. Professional Manufacturing:Home Etching:Pros: Immediate results, good for learning, no minimum order quantityCons: Limited to single or double-layer boards, requires chemicals (ferric chloride or cupric chloride), lower precision, manual drilling required, no solder mask or silkscreen, time-consumingProfessional Manufacturing (Recommended for 2025):Pros: High quality, multi-layer capability, solder mask and silkscreen included, plated through-holes, very affordable (as low as $2-5 for small boards), quick turnaround (2-7 days)Cons: Requires waiting for shipping, minimum order quantities (though often just 5 pieces)Popular PCB Manufacturers in 2025:JLCPCB - Very affordable, fast turnaround, assembly services availablePCBWay - Good quality, competitive pricing, excellent customer serviceOSH Park - USA-based, high quality, purple PCBsALLPCB - Budget-friendly optionEurocircuits - European manufacturer, excellent qualitySeeed Studio - Fusion PCB service, good for prototypesMany manufacturers now offer PCB assembly services (PCBA), where they'll solder the components for you. This is increasingly affordable and saves significant time, especially for SMT components.Frequently Asked Questions (FAQ)1. How much does it cost to make your own circuit board?As of 2025, PCB manufacturing costs have decreased significantly. For prototypes, you can get simple PCBs manufactured for as little as $2-5 for 5 pieces (100mm x 100mm or smaller). More complex boards with multiple layers, special materials, or larger sizes will cost more. PCB assembly costs typically range from $0.50 to $5 per component placement, depending on component type and quantity. For a complete assembled board, expect to pay $20-100 for small quantities, with costs decreasing significantly for larger production runs (hundreds or thousands of units).2. How do you design and specify printed circuits?The PCB design process follows these steps:Schematic capture - Create the electrical circuit diagramSimulation - Verify circuit functionality (optional but recommended)Component selection - Choose specific parts with appropriate footprintsBoard setup - Define board dimensions, layers, and design rulesComponent placement - Position components strategicallyRouting - Connect components with copper tracesPower plane design - Create ground and power distribution layersDesign rule check (DRC) - Verify manufacturabilityGenerate manufacturing files - Export Gerber and drill filesCreate BOM - Bill of Materials for component procurementAssembly documentation - Create assembly drawings and pick-and-place files3. What does a printed circuit board do?A printed circuit board serves two primary functions: it provides mechanical support for electronic components and creates electrical connections between them using conductive copper pathways. The PCB eliminates the need for point-to-point wiring, making electronic devices more reliable, compact, and manufacturable at scale. Modern PCBs also provide electromagnetic shielding, heat dissipation, and can integrate additional features like impedance-controlled traces for high-speed signals, embedded components, and flexible or rigid-flex sections.4. What is a printed circuit board called?Printed circuit boards are known by several names:PCB - Most common abbreviationPrinted Wiring Board (PWB) - Emphasizes the wiring aspectPrinted Circuit Assembly (PCA) - When components are already mountedPrinted Circuit Board Assembly (PCBA) - Fully assembled boardCircuit Board - General termThe term "printed" refers to the manufacturing process where the circuit pattern is printed onto the board, though modern manufacturing uses photolithography rather than literal printing.5. What is the difference between PCB and PWB?The terms PCB (Printed Circuit Board) and PWB (Printed Wiring Board) are often used interchangeably, but there's a subtle distinction:PWB typically refers to the bare board with only copper traces, pads, and holes - no components mountedPCB can refer to either the bare board or the assembled board with componentsPCBA or PCA specifically refers to the assembled board with all components solderedIn practice, most people use "PCB" to refer to both bare and assembled boards, with context determining the meaning.6. What is a printed circuit board made of?PCBs consist of several layers:Substrate - Usually FR-4 (fiberglass-reinforced epoxy), but can be FR-1, FR-2, CEM-1, CEM-3, polyimide (for flexible PCBs), aluminum (for LED boards), or Rogers material (for high-frequency applications)Copper layers - Typically 1 oz/ft² (35 μm) or 2 oz/ft² (70 μm) thickness, laminated to the substrateSolder mask - Protective polymer layer (usually green, but available in other colors) that prevents solder bridges and protects copper from oxidationSilkscreen - White (or other color) ink layer showing component designators, logos, and other markingsSurface finish - Protects exposed copper pads; options include HASL (Hot Air Solder Leveling), ENIG (Electroless Nickel Immersion Gold), OSP (Organic Solderability Preservative), or immersion silver/tin7. What does PCB stand for?PCB stands for Printed Circuit Board. It's the foundation of modern electronics, providing both mechanical support and electrical connections for electronic components. PCBs replaced earlier point-to-point wiring and wire-wrap construction methods, enabling the mass production of reliable, compact electronic devices. The "printed" aspect refers to the manufacturing process where circuit patterns are created using photolithographic techniques, similar to how photographs are developed.8. Why are PCBs green?PCBs are traditionally green due to the color of the solder mask - a protective coating applied over the copper traces. The green color became standard for several reasons:Historical - Early solder mask materials naturally produced a green colorVisibility - Green provides good contrast for inspection, making it easier to see traces and identify defectsEye strain - Green is easier on the eyes during prolonged inspection and assembly workCost - Green solder mask is the most common and therefore least expensiveHowever, modern PCBs come in many colors: blue, red, black, white, yellow, purple, and even matte black. Color choice is now often aesthetic, though some colors (like black) can make inspection more difficult. High-end products often use black PCBs for a premium appearance, while purple has become popular in the maker community.9. How do you choose a PCB material?PCB material selection depends on your application requirements:By Application Type:Standard/General Purpose - FR-4 (most common, good for frequencies up to 1-2 GHz)High Frequency/High Speed (>2 GHz) - Rogers RO4003C, RO4350B, or Isola materials with controlled dielectric constantFlexible Circuits - Polyimide (Kapton) or polyesterRigid-Flex - Combination of FR-4 and polyimideLED/High Power - Aluminum or copper core for better heat dissipation (Metal Core PCB - MCPCB)High Temperature - Polyimide or high-Tg FR-4 (Tg > 170°C)Low Cost - FR-1, FR-2, or CEM-1 (phenolic paper-based)Key Material Properties to Consider:Dielectric constant (Dk) - Affects signal speed and impedanceLoss tangent (Df) - Signal loss at high frequenciesGlass transition temperature (Tg) - Maximum operating temperatureThermal conductivity - Heat dissipation capabilityCoefficient of thermal expansion (CTE) - Dimensional stability with temperature changesMoisture absorption - Affects reliability in humid environments10. Why do we use PCB instead of breadboard circuits?While breadboards are excellent for prototyping, PCBs offer significant advantages for final products:Advantages of PCBs over Breadboards:Reliability - Permanent solder connections vs. friction contacts that can loosenDurability - Resistant to vibration, shock, and environmental factorsCompactness - Much smaller footprint, especially with SMT componentsPerformance - Lower parasitic capacitance and inductance, better for high-frequency circuitsCurrent capacity - Wider traces can handle more current safelyReproducibility - Identical boards can be manufactured consistentlyProfessional appearance - Clean, polished look for commercial productsCost-effective at scale - Very cheap per unit in production quantitiesHeat management - Can integrate heat sinks, thermal vias, and metal coresEMI/EMC compliance - Better electromagnetic compatibility through proper grounding and shieldingWhen to Use Each:Breadboard - Initial prototyping, learning, testing concepts, temporary circuitsPCB - Final products, permanent installations, high-frequency circuits, production quantities, professional projectsConclusionCreating your own PCB has never been more accessible. With free or affordable design software, online tutorials, and inexpensive manufacturing services, anyone can bring their electronic projects to life. Whether you're a hobbyist building your first LED blinker or an engineer developing a complex IoT device, the PCB design and manufacturing process follows the same fundamental steps.Start with simple projects to learn the basics, and gradually tackle more complex designs as your skills improve. The maker community is vibrant and supportive, with countless resources, forums, and tutorials available online. Don't be intimidated - your first PCB might not be perfect, but each project will teach you valuable lessons.Remember: every expert PCB designer started exactly where you are now. The key is to start designing, learn from mistakes, and keep improving. Happy designing!

LMX3268VBHXThe International Labor Organization (ILO) points out that some 40 million tons of electronic waste (including computers, mobile phones, printers, etc.) are produced every year. The prospect is that this amount will increase even more over time, as electronic devices with new functions and more attractive designs are constantly appearing, stimulating new purchases from the consumer without the old product being out of date. Being present is most electronic devices, Printed Circuit Boards, also known as PCBs, are among the most discarded parts. They are made up of a plastic board and fibrous materials (such as plastic polymers) and a thin film of metallic substance (copper, silver, gold or nickel). These films form “tracks” or “paths” that will be responsible for the electrical conduction done by the electronic components. They can also have other materials in their composition, such as alloys, which have distinct melting points, thus allowing for manipulation and arrangement. There are several alloys available to be used, such as cerrobend, low melting point alloy or fusible alloys. Recycling electronic waste is much needed, because of the chemical components in its composition, with some of them being toxic – they can cause problems if they are disposed of incorrectly. For PCBs specifically, their recycling process involves quite some steps. Mechanical processesIt starts with a pre-treatment system that aims to separate metals, polymer materials and ceramics. After this step, the metals are sent to the metallurgical refining process. The techniques that make up this process are: comminution, classification and separation. Comminution is the technique used to reduce particle size and release metals for future concentrations. In the classification step, the material particles obtained by the previous process must be separated or classified according to their size. After the steps of comminution and classification, the enrichment of the material takes place by means of separation techniques: the parts that are interesting for the refining process of the metal are separated, discarding any impurities. In the case of circuit boards, the difference in electrical conductivity between metals and non-metals is a fundamental condition for the good result of the technique. Non-conductive materials (polymers and ceramics) can be separated from conductors (metals). Some techniques employed for this purpose are explained below. Pyrometallurgy processIt is a metallurgical process that uses high temperatures to produce pure metals, alloys or intermediate compounds. Pyrometallurgy requires high energy consumption to reach the appropriate temperatures for each stage of the process. There are several steps in the process, from the drying of the raw material to the refining of the final product. The chemical transformation step to be used will depend on the material in question. The best known are calcination (decomposition by heat in the presence of oxygen), roasting (calcination applied to sulphides) and pyrolysis (decomposition by the action of heat in an environment with little or no oxygen). Some of the major problems in the use of pyrometallurgical processes are the possibility of emission of toxic compounds such as dioxins and the high energy consumption. Hydrometallurgy processIt consists of the separation of metals. Some of the advantages of this method are the energy savings and the lower pollution of the environment. Electrometallurgy processIt is a process of refining metals through electrolysis. During electrolysis, metals without the impurities undergo electrodeposition, in which metals such as copper, zinc, cadmium, aluminum, precious metals, among others, can be recovered with a high degree of purity; Biometallurgy processThis process uses the action of microorganisms and minerals to recover valuable metals. This process requires a lot of time and metal needs to be exposed to microbial action. Where to recycle?If your computer and its PCBs are not broken but only technologically lagged, look for specialized places that accept donations of these items. You can also resell those components on the Internet, for example. However, and regardless of the final decision, always be sure that the final destination to be given to these materials is a proper one, always avoiding to harm the environment. Ref.IC ChipsPCB2B12ALMZ12001EXT

The days of making a prototype board by hand by the artist are long gone. For many years, the ability to make one's own PCBs was the characteristic of an ideal design engineer (or a big shot electronic hacker). The art of making a homemade PCB has progressed over time, beginning with the use of ferric chloride solutions and progressing to laser toner printers and, more recently, 3D printers. The commercial PCB manufacturing process has evolved in tandem with the evolution of "homemade technology." Over the last few decades, the manufacturing process of the PCB (and the businesses involved in it) have expanded by leaps and bounds. The use of materials changed, and the cost of production dropped like never before, ushering in the age of affordable PCB prototype service by full scale pcb manufacturers. Designers seldom approached a full-service PCB manufacturer to print a prototype in the early days. Designers either created a prototype of their own or, in the majority of cases, approached a small-scale board manufacturer to have their images created. In those days, the expense of printing a prototype was prohibitively expensive. As technologies and processes have advanced, both designers now shift to full-service PCB manufacturers for prototyping. The advancement of technology and modern processes allowed full-scale PCB manufacturers to print prototypes and small volumes at a much lower cost than in the past. Let's dig a little deeper to see what are the 10 most important items a designer should consider when selecting a PCB prototype service are.How to Choose the Right PCB Prototype Service ? 1. CostThe first criterion to consider when selecting a PCB partner should be consistency. The prototype you print should be error-free (like a missing print or a small drill hole than the actual design). The materials selected by the PCB printing company should be free of flaws. All of these factors add up to consistency. The PCB manufacturer's quality is critical for getting your prototype correct and working. You may evaluate quality by examining the services provided by a PCB manufacturer. Examine how seriously they take a prototype client when it comes to PCB prototype operation. What is the significance of this PCB prototype service business to a specific manufacturing company? You may also speak with the customer service representatives to see how knowledgeable they are about the prototype service. A good company/manufacturer that is serious about prototype service will almost certainly have a separate segment dedicated to prototype service only. Their website will have details on the subject. Customer service will be very knowledgeable and supportive. Finally, before making a decision, conduct research on the internet about a specific manufacturer, especially in forums and communities. ALLPCB, Sunstone, EuroCircuits, 4PCB, and EpecTec are some PCB manufacturers that provide high-quality prototype services based on my experience (and other reviews). 4PCB is the only one of these five firms that does not have a dedicated section for prototype printing. Sunstone and AllPCB have whole parts devoted to prototyping services. Services for all PCBs start as low as $5 USD. 2. MOQ (Minimum Order Quantity)The minimum order quantity requested by the manufacturer, in my opinion, should be the second criterion in selecting a PCB prototype service. A prototype is a concept that is in its early stages and is subject to alteration. If a PCB manufacturer wants you to order a much larger minimum quantity (usually measured and quoted in square inches) than you can afford (or far exceeds your budget), you can avoid that manufacturer. The majority of manufacturers are willing to negotiate on this point.As a designer, you will negotiate with the manufacturer for potential orders. The main point here is that a MOQ that appears low or inexpensive to one designer (or design/production company) can be prohibitively expensive to another.33. CostThe cost/price quoted by the PCB manufacturer is the third factor to consider. In reality, the PCB printing industry is a highly competitive one. With the internet at their fingertips (4G and smartphones), everyone can search and compare quotes from various PCB manufacturing companies in a matter of hours. Because of the highly competitive climate, it is unlikely that there would be a significant difference in prices quoted by various manufacturers. Bear in mind that quality and price do not go together! Manufacturers with superior technologies, high-quality products, and overall quality would undoubtedly charge a higher price than their competitors. My advice is always to prioritize quality over price. Consider the following scenario: you had to reprint the prototype due to poor quality or a problem on the manufacturer's end. Weighing the additional cost (for reprinting) and time loss, I would probably choose a reputable manufacturer with good quality, even if the price is slightly higher.4. Turnaround TimeFast delivery of your prototype from the order date is a critical criterion to consider when selecting a PCB prototype service partner. It's pointless if a manufacturer takes two weeks from the order date to ship your prototype. The majority of prototype projects have strict deadlines. Typically, a manufacturer quotes 5 days or more to ship the prototype from the day the order is approved (Gerber files accepted). There are providers that provide quicker service as well; for example, ALLPCB provides prototype delivery within 2 to 3 days of Gerber file approval. EuroCircuits, a well-known PCB manufacturer, charges between 2 and 7 days for their prototype operation. Sunstone, another big player, provides a time guarantee in which they guarantee a refund if they fail to ship on the agreed-upon date. However, they are not as fast as the ALLPCB men, typically taking more than 5 days to complete an order (the maximum lead time of Sunstone is around 3 weeks). 5. Customization OptionsPrototypes are subject to alteration until they take on their final form. They can change scale, parts, and, in some cases, the entire form. It is difficult for any manufacturer to provide customizations on the fly. If customizations are important to you, look for a manufacturer who has the necessary equipment and facilities to provide what you want. 6. International DeliveryCheck to see if the manufacturer you've narrowed down offers delivery to your country, particularly if you're working with an overseas printing business. The majority of full-service manufacturers have foreign shipping to almost all business countries. The majority of designers now work with PCB manufacturers in China, who provide high-quality PCBs at a low cost. The majority of these well-established Chinese businesses provide worldwide shipping. 7. Instant Quote Facility The majority of well-known manufacturers provide instant quotes on their websites. Often go with manufacturers who provide this online quote service. Instant quotes provide us with an idea of the costs involved. 8. Industry ExperienceUnique and advanced projects need prior expertise in a specific industry. For example, if you're working on a communication technology project, it's best to work with a vendor that has a proven track record in the same industry. Similarly, as the number of layers on your board grows, go with existing players who are well-versed in multilayer printing. 9. Multi Disciplinary Services If you intend to outsource services such as PCB assembly, you should look for a manufacturer that provides a variety of options.10. Safe Packing & ShippingFinally, be certain that the manufacturer you choose adheres to healthy packaging and shipping practices. Nobody wants their goods to be harmed during delivery. If you need faster delivery, see if the manufacturer provides express shipping (often at a higher price). Ref:KY66-G6EU-134P-US DC6KY66-EF2-5NUKY66-G6K-2G-Y-DC4.5