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Have you noticed that now more and more of our lighting is using led lighting.What is LED? Compared to the traditional light bulbs, LEDs have lower power consumption, longer lifetime and higher energy efficiency. In the PCB industry,when we say LED PCB, it refers to the pcb used for LED lighting, if you are looking for a suitable LED PCB for your lighting system, this article may bring you something. WHAT ARE LEDS COMPOSED OF?LED is an initial light-emitting diode that produces light when an electric current passes through. LEDs typically have negative and positive electrodes, which generate light in the visible light region.The LEDS are glued to the PCB by soldering process and have electrical connections for lighting.Since light-emitting diodes dissipate a lot of heat when they are in use, when you are designing LED, the metal core is usually the best choice for LED PCB, it is because that it dissipates heat more faster. Among them, the metal material aluminum is the most widely used
When high-speed PCB wiring is used, the signal will reflect in the transmission channel when the impedance does not match during transmission; The fundamental way to eliminate reflection is to make the impedance of the transmitted signal match well. So, what wiring rules should be followed for impedance matching of high-speed PCB signals? Due to the larger difference between the load impedance and the characteristic impedance of the transmission line, the greater the reflection, it is necessary to make the characteristic impedance of the signal transmission line equal to the load impedance as much as possible; At the same time, it is also important to note that there should be no sudden changes or corners in the transmission line on the PCB, and to try to maintain continuous impedance at each point of the transmission line, otherwise there will also be reflections between different sections of the transmission line. This requires that the following wiring rules must be followed wh
Circuit boards are known as the "mother of electronic components" and are essential basic accessories in electronic devices. Nowadays, there are many circuit board manufacturers on the market. With the development of circuit board production technology, many PCB buyers have gradually begun to understand the basic characteristics of Shenzhen circuit board manufacturers. So, what are the characteristics of excellent Shenzhen circuit board manufacturers? 1、 Having a strong R&D team The reason why Shenzhen circuit board manufacturers are able to produce high-quality circuit boards is that they have a professional research and development team that can provide plasticity suggestions for prototype products in the design stage. In addition, excellent core technical personnel from manufacturers have years of experience in circuit board research and development, which enables them to produce PCB circuit board products with quality assurance strictly in accordance with industry standards a
When customers customize PCB products, they always make more in case of unexpected needs. Over time, there may be the phenomenon of PCB boards expiring but being ignored by oneself. So, what are the hazards of using expired PCB circuit boards? 1. Expired PCB may cause oxidation of surface solder pads After oxidation of the solder pad, it will cause poor soldering, which may ultimately lead to functional failure or the risk of parts falling out. The antioxidant effect of different surface treatments on circuit boards may vary, and in principle, ENIG requires that they be used up within 12 months; OSP requires it to be used up within six months, and it is recommended to follow the shelf life of the PCB factory to ensure quality. 2. Expired PCB may absorb moisture and cause board explosion When the circuit board undergoes soldering after moisture absorption, it may cause problems such as popcorn effect, board explosion, or delamination. Although this problem can be solved through
Nowadays, the development of circuit boards is becoming more mature, and their technical level is constantly being updated. A PCB circuit board needs to go through various production processes from prototype to finished product. Sinking process is a commonly used surface treatment process in PCB circuit boards; Next, let the Shenzhen PCB factory take you to understand the process of circuit board gold deposition. The gold deposition process is to deposit a nickel gold coating with stable color, good brightness, flat coating, and good solderability on the surface of PCB printed circuits through chemical reactions; Because of weak adhesion, it is also known as soft gold. Because sinking gold is softer than plating gold, making gold fingers from sinking gold plates is not wear-resistant. The PCB board after sinking gold presents a golden yellow color, which is brighter and more beautiful than the color of gold plating. The Shenzhen PCB factory has summarized its characteristics as fo
The problem of blackening of the electroplating gold layer often occurs, which affects the quality and performance of the circuit board. So, what are the reasons for the blackening of the electroplating gold layer on PCB board copying? 1. Thickness control of nickel plating layer PCB electroplating gold layer is generally very thin, reflected on the surface of electroplating gold, many of which are caused by poor performance of nickel electroplating. Generally, a thin nickel plating layer can cause the appearance of the product to turn white and black. Generally, it is necessary to electroplate the nickel layer thickness to around 5UM to be sufficient. 2. Condition of plating nickel cylinder solution If the nickel cylinder solution is not well maintained for a long time and carbon treatment is not carried out in a timely manner, the nickel layer electroplated will easily produce flaky crystals, increase the hardness and brittleness of the coating. Serious problems can result in b
PCBA, which refers to the assembly, mounting, and welding of PCB components, is the core process in PCBA. So, what are the precautions for PCB processing by Shenzhen circuit board manufacturers? 1、 Transportation: To prevent damage to PCBA, during transportation, it is necessary to: 1. Container: Anti static turnover box. 2. Isolation material: anti-static pearl cotton. 3. Placement spacing: There is a distance greater than 10mm between boards and between boards and boxes. 4. Placement height: There is a space greater than 50mm from the top surface of the turnover box. 2、 PCBA processing and washing requirements: 1. Board surface requirements: Clean, with no stains on Wuxi beads and component pins. 2. Devices that should be protected during board washing: wires, connecting terminals, relays, switches, polyester capacitors, and other devices. 3、 Component requirements: All components must not exceed the edge of the PCB board after installation. 4、 Welding requirements: 1.
Printed circuit boards (PCBs) are an indispensable part of electronic devices, and their performance and reliability directly affect the operation of the entire system. PCB (Printed Circuit Board), also known as Printed Circuit Board (PCB) in Chinese, is an important electronic component that supports electronic components and serves as a carrier for the electrical interconnection of electronic components. Due to its use of electronic printing technology, it is called a "printed" circuit board. Cabling is a key step in PCB design, which determines the performance and stability of the circuit board. This article will explore the wiring principles and practical techniques of PCB boards to help engineers achieve better results in design. Wiring principles Following the circuit schematic diagram Wiring should strictly follow the circuit schematic to ensure correct wiring connections and prevent short or open circuit problems. During the wiring process, each component in the circuit
During the production process of PCB circuit boards, due to the inability of printed solder paste and solderless PCB assembly boards to fix the test end of thermocouples, it is necessary to use the actual welded product for temperature testing. So, how to conduct PCB board temperature limit testing? 1、 Select test points: Based on the complexity of the PCB assembly board and the number of channels in the collector, select at least three representative temperature test points that can reflect the high, medium, and low temperatures on the PCB surface assembly board. 2、 Fixed thermocouple: Use high-temperature solder to weld the test ends of multiple thermocouples onto the test points (solder joints), and the solder on the original solder joints must be cleaned before welding; Alternatively, use high-temperature adhesive tape to attach the test ends of the thermocouples to each temperature test point on the PCB. 3、 Insert the other end of the thermocouple into the machine table at
PCBA, which refers to the assembly, mounting, and welding of PCB components, is the core process in PCBA. So, what are the precautions for PCB processing by Shenzhen circuit board manufacturers? 1、 Transportation: To prevent damage to PCBA, during transportation, it is necessary to: 1. Container: Anti static turnover box. 2. Isolation material: anti-static pearl cotton. 3. Placement spacing: There is a distance greater than 10mm between boards and between boards and boxes. 4. Placement height: There is a space greater than 50mm from the top surface of the turnover box. 2、 PCBA processing and washing requirements: 1. Board surface requirements: Clean, with no stains on Wuxi beads and component pins. 2. Devices that should be protected during board washing: wires, connecting terminals, relays, switches, polyester capacitors, and other devices. 3、 Component requirements: All components must not exceed the edge of the PCB board after installation. 4、 Welding requirements: 1.
Printed circuit boards (PCBs) are an indispensable part of electronic devices, and their performance and reliability directly affect the operation of the entire system. PCB (Printed Circuit Board), also known as Printed Circuit Board (PCB) in Chinese, is an important electronic component that supports electronic components and serves as a carrier for the electrical interconnection of electronic components. Due to its use of electronic printing technology, it is called a "printed" circuit board. Cabling is a key step in PCB design, which determines the performance and stability of the circuit board. This article will explore the wiring principles and practical techniques of PCB boards to help engineers achieve better results in design. Wiring principles Following the circuit schematic diagram Wiring should strictly follow the circuit schematic to ensure correct wiring connections and prevent short or open circuit problems. During the wiring process, each component in the circuit
During the production process of PCB circuit boards, due to the inability of printed solder paste and solderless PCB assembly boards to fix the test end of thermocouples, it is necessary to use the actual welded product for temperature testing. So, how to conduct PCB board temperature limit testing? 1、 Select test points: Based on the complexity of the PCB assembly board and the number of channels in the collector, select at least three representative temperature test points that can reflect the high, medium, and low temperatures on the PCB surface assembly board. 2、 Fixed thermocouple: Use high-temperature solder to weld the test ends of multiple thermocouples onto the test points (solder joints), and the solder on the original solder joints must be cleaned before welding; Alternatively, use high-temperature adhesive tape to attach the test ends of the thermocouples to each temperature test point on the PCB. 3、 Insert the other end of the thermocouple into the machine table at
The problem of blackening of the electroplating gold layer often occurs, which affects the quality and performance of the circuit board. So, what are the reasons for the blackening of the electroplating gold layer on PCB board copying? 1. Thickness control of nickel plating layer PCB electroplating gold layer is generally very thin, reflected on the surface of electroplating gold, many of which are caused by poor performance of nickel electroplating. Generally, a thin nickel plating layer can cause the appearance of the product to turn white and black. Generally, it is necessary to electroplate the nickel layer thickness to around 5UM to be sufficient. 2. Condition of plating nickel cylinder solution If the nickel cylinder solution is not well maintained for a long time and carbon treatment is not carried out in a timely manner, the nickel layer electroplated will easily produce flaky crystals, increase the hardness and brittleness of the coating. Serious problems can result in
The PCB circuit board is only a complete device after processing, and can be used in applied electronic products. The PCBA process is the combination of SMT processing and DIP processing. Today, the editor will share with you what processes are included in the processing of PCB by Shenzhen circuit board manufacturers. 1、 Single sided DIP insertion PCB boards that require plugins can be welded and fixed by workers after inserting electronic components, followed by wave soldering, cutting and washing the board. 2、 Single sided SMT mounting Add solder paste to the component pad, and after the solder paste printing is completed, the relevant electronic components are reflow soldered and then reflow soldered. 3、 Single sided mixed packaging PCB boards are printed with solder paste, installed with electronic components and fixed by reflow soldering. After quality inspection is completed, DIP insertion is performed, followed by wave soldering or manual soldering. 4、 Double sided SM
PCBA is the entire process of SMT loading through PCB empty boards, followed by DIP plugins; Placement and welding are the core processes in PCBA. So, what are the requirements for chip mounting and welding in the PCBA processing process? 1、 PCBA SMT processing process requirements: 1. Based on customer Gerber files and BOM sheets, create SMT production process files and generate SMT coordinate files. 2. Check if all production materials are ready and confirm the PMC plan for production. 3. Conduct SMT programming and create a homepage for verification. 4. According to the SMT process, make laser steel mesh. 5. Perform solder paste printing to ensure that the printed solder paste is uniform and of good thickness. 6. Mount the components onto the circuit board using an SMT mounting machine, and perform online AOI testing if necessary. 7. Set a perfect reflow soldering furnace temperature curve to allow the circuit board to flow through reflow soldering, and the solder paste
Many beginners are always confused about the rules and requirements for PCB circuit board sampling fees. What materials do they need to provide? Let the engineer explain this process to you: 1、 How much do I charge for PCB sampling? Firstly, it depends on what type of board is used, such as FR4, high TG board, and brand benefits. The plates are different, and the prices are also different. In addition, according to the design drawings, the smaller the line width and spacing, the more holes there are, and the more precise it is, the higher the cost. Looking at the surface treatment, sinking gold and gilding are more expensive than tin and OSP. Four Look at Quantity . According to the delivery date, PCB boards that require expedited delivery are cheaper than those that require regular delivery. 2、 What do I need to provide for PCB sampling? Information that needs to be provided to the manufacturer for quotation, drawings generally provide GEBER documents, with clear process requ
With the development of PCB technology towards high density and refinement, the role of multi-layer PCB boards is becoming increasingly important and widely used in various fields. Below is the engineer's interpretation of several common questions about multi-layer PCB circuit boards: 1. How many layers can a multi-layer PCB board have at most? PCB boards were initially mainly composed of single or double panels, but later with the development of technology, multi-layer PCB boards were needed to achieve the interaction of multi-layer circuits. Components range from simple single sided boards to 4, 6, 8, 10, 12, and even 22 or more layers. There is no conclusion regarding the maximum number of layers on a multi-layer PCB board. For research and development institutions, the number of layers of a PCB depends on the product requirements and functions implemented by the electronic PCB application. 2. Is it better to have more layers of multi-layer PCB boards? Generally speaking, the
PCB ink plays a role in protecting the copper foil during the production of PCB circuit boards, preventing the copper skin from being exposed, thereby affecting the subsequent processes; The commonly used ink colors are white oil, green oil, black oil, blue oil, red oil, and butter. So, what are the precautions for using PCB ink? In any case, the temperature of the ink must be maintained between 20-25 ℃, otherwise it will affect the viscosity of the ink and the quality and effectiveness of screen printing. Especially when ink is stored outdoors or at different temperatures, it must be placed at ambient temperature for a few days before reuse or until the ink barrel reaches the appropriate temperature for use. 2. Before use, the ink must be thoroughly and carefully mixed manually or mechanically. If air enters the ink, it should be left to stand for a period of time before use; If dilution is required, first mix thoroughly and then test its viscosity. The ink bucket must be sealed
Many newcomers often confuse nickel palladium plating with nickel gold plating. So, what is the difference between PCB sample nickel palladium plating and nickel gold plating? Nickel palladium plating is a non selective surface processing process that involves depositing a layer of nickel, palladium, and gold onto the surface of the copper layer of the printed circuit using chemical methods in PCB sampling. Electroplating nickel gold refers to the process of making gold particles adhere to PCB boards through electroplating, which is also known as hard gold due to its strong adhesion; This process can greatly increase the hardness and wear resistance of PCBs, effectively preventing the diffusion of copper and other metals. The difference between chemical nickel palladium gold and electroplating nickel gold: Similarities: 1. Both belong to important surface treatment processes in PCB sampling; 2. The main application field is wiring and connection technology, which is suitable
Aluminum substrate is a metal based copper clad plate with good thermal conductivity, electrical insulation performance, and mechanical processing performance. Let the Shenzhen PCB manufacturer take you to understand what aluminum substrates are. 1、 Characteristics of aluminum substrate 1. Adopting surface mount technology; 2. Extremely effective treatment of thermal diffusion; 3. Reduce product operating temperature, improve product power density and reliability; 4. Reduce product volume and assembly costs; 5. Replace fragile ceramic substrates. 2、 Structure of aluminum substrate The aluminum substrate consists of copper foil, thermal insulation layer, and metal substrate: Copper foil: The thickness of the copper foil for the circuit is between loz and 10oz. Thermal insulation layer: It is a low thermal resistance thermal insulation material. Metal substrate: generally aluminum based copper clad plate and traditional epoxy glass cloth laminated plate. Explanation: 1.
PCB circuit boards are prone to malfunctions during use, which involves maintenance. So, what are the issues to pay attention to when repairing PCB circuit boards? 1、 Understand the vulnerable components on the circuit board 1. Areas with unreasonable design are most prone to malfunctions Firstly, there is a heat dissipation issue, as many PCB boards are damaged due to poor heat dissipation design; Secondly, there is copper foil wire. The copper foil of circuit board power lines with poor quality is very thin and easily burnt out due to overcurrent. 2. Frequently used areas are prone to malfunctions For example, the drive motor of the circuit board, the shaft, the switch tube of the switching power supply, the operation panel, etc. 3. Components with heavy loads, high power, and high operating voltage are most likely to malfunction The power supply, driving circuit, power control device, operational amplifier, etc. of the circuit board are the most easily damaged. 4. Protec
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