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How to use a pcb prototype board?
Friday, December 20th, 2024

How to use a pcb prototype board? To use a PCB prototype board, you need to prepare components and tools according to the design, check the board, lay out the components reasonably and solder them. After soldering, first visually inspect, then power on and test each module with an oscilloscope, etc. If there is a problem, check the connection, change components, and adjust parameters to debug. Clean and store it after use.

What is a PCB prototype?

PCB prototypes are early samples of products, mainly used to test design concepts and verify the feasibility of designs. It not only tests basic user functions, but also needs to have certain functionality to ensure that the overall function of the design can operate normally. During the PCB prototype production process, engineers can test different PCB designs and manufacturing specifications to find the best solution.

How to use a pcb prototype board?

The role of PCB prototypes:

  • Shorten time: Through PCB prototypes, design engineers can quickly and accurately test design problems and reduce the number of design iterations, thereby shortening the design cycle and reducing costs.
  • Improve customer satisfaction: Customers can see product prototypes in advance, which can better communicate needs, reduce misunderstandings and rework during design and production, and ensure that the final product meets customer needs.
  • Ensure design feasibility: PCB prototypes can test circuit boards before production, discover and fix potential design defects, and avoid rework and cost waste after production.

How to make PCB prototyping?

The following are brief steps to make PCB prototypes:

  • Step 1: Design circuit schematics

Use the schematic capture tool to select components according to circuit functional requirements and connect them logically in the software. After drawing, check its logic and integrity, and use the electrical rule check function to troubleshoot errors to ensure that it meets the requirements.

  • Step 2: Plan PCB layout

Import components into the layout software, place them reasonably according to component characteristics, plan wiring at the same time, take into account power lines, ground lines and high-speed signal wiring requirements, and adjust components and wiring to meet rules and space restrictions.

  • Step 3: Generate production files

Generate Gerber files, make BOM materials list at the same time, and communicate with manufacturers to ensure that the files meet production requirements.

  • Step 4: Select the manufacturing method

Choose breadboard (flexible but high contact resistance, etc.), perforated board (needs soldering, more stable but more complicated wiring) or PCB manufacturing (high quality but high cost, long cycle) according to the complexity, size and budget of the circuit.

  • Step 5: Manufacture PCB board

Breadboard directly plugs components and connects jumpers; perforated board needs to solder components; PCB manufacturing gives relevant documents to manufacturers for production according to the process, and maintains communication during the process to ensure quality and delivery.

  • Step 6: Drilling
How to use a pcb prototype board?

Choose a drill bit according to the size of the component pin, use a drilling machine to drill vertically, control the depth, especially for multi-layer boards, and clean up the debris in the hole after drilling.

  • Step 7: Soldering components

After cleaning the component pins, place them in the corresponding position of the PCB, use a soldering iron, solder wire (hot air gun for patch, etc.) to solder according to specifications, and check the quality of the solder joints after soldering to ensure that there are no problems such as false soldering and short circuits.

  • Step 8: Test the circuit board

Perform visual inspection (look at the appearance, component installation, solder joints, etc.), functional testing (input signals according to the designed functions to see if the output meets expectations) and electrical testing (use instruments to measure whether the electrical parameters are normal) to promptly troubleshoot and repair problems.

How much does a PCB prototype cost?

The cost of a PCB prototype varies depending on many factors, mainly including circuit board size, number of layers, materials, process complexity, etc.

  • Circuit board size: The larger the circuit board, the higher the cost.
  • Number of layers: Multi-layer circuit boards are usually more expensive than single-layer or double-layer circuit boards because the manufacturing process is more complicated.
  • Material type: Different materials have different costs, and high-performance materials are usually more expensive.
  • Surface treatment: Surface treatment processes such as gold plating and immersion gold will affect the cost.
  • Minimum line width, line spacing, aperture: The higher the accuracy requirements of these parameters, the higher the cost.
  • Special requirements: Additional requirements such as impedance control and special markings will increase the cost.

What is the difference between prototype PCB and assembly?

The main difference between prototype PCB and assembly lies in their purpose, quantity, production cycle and cost.

1. Purpose and quantity

  • Prototype PCB: Mainly used to test and verify the design, ensure the feasibility and performance of the design in practical applications, and its quantity is usually large.
  • Assembly: Usually refers to mass production, the quantity is usually more than 500 pieces, or even thousands of pieces.

2. Production cycle and cost

  • Prototype PCB: The production cycle is short, usually no more than 10 days, suitable for rapid testing and adjustment of the design. Although the unit price is high, the total cost is low because problems can be discovered and solved in time to avoid losses during mass production.
  • Assembly: The production cycle is long, generally 20-25 days. The unit price is low, but the total cost is high because a large number of products need to be produced.

3. Design and production process

  • Flexibility: The prototype PCB production process is more flexible and can be adjusted and modified according to design requirements.
  • Quality control: The quality control standards of prototype PCB can be moderately relaxed to complete production faster. Mass production requires strict quality control to ensure that each board is defect-free.

Is a breadboard a protoboard?

A breadboard is a prototype board, also known as a solderless breadboard or a universal circuit board. It is mainly used for prototyping and experimental verification of electronic circuits. It can quickly assemble and test circuits without soldering.

How to use a pcb prototype board?

The structure of a breadboard includes a conductive hard substrate, an insulating material layer, and an epoxy glass cloth board or a double-sided glass cloth board covered with a copper layer. There are many holes on the top for plugging electronic components, such as DIP (dual in-line package), SMD (surface mount device) and THT (through-hole technology).

The breadboard uses U-shaped metal contacts to hold component leads and wire segments inserted through holes, and uses spring tension to fix components, providing a flexible and convenient way to connect circuits.

The use scenarios of breadboards are very wide, suitable for prototyping and debugging of various electronic projects. Due to its characteristics of not requiring soldering, breadboards are particularly suitable for beginners and experimenters who need to frequently replace components.

What is the difference between PCB prototype and breadboard?

PCB prototype and breadboard have the following main differences in prototyping:

1. Usage:

  • Breadboard: When using breadboard for circuit construction, you only need to insert the component pins into the corresponding small holes, without soldering, which is very suitable for temporary circuit testing and small-scale prototyping.
  • PCB prototype: You need to use circuit design software to draw a circuit diagram first, and then convert the design into conductive lines and component layout on the PCB. The PCB is made through a series of processes, and finally the components are soldered to the PCB to complete the circuit construction.

2. Advantages and disadvantages:

Breadboard:

  • Advantages: easy to use, flexible, can quickly build and modify circuits; no professional tools and equipment are required, suitable for beginners and small-scale production.
  • Disadvantages: The circuit connection is not stable enough and is easily affected by vibration and temperature difference; it is not suitable for large-scale production and complex circuit design; after long-term use, the metal contact points are easily oxidized and cause poor contact.

PCB prototype:

  • Advantages: The circuit connection is stable and reliable, suitable for the design and production of various complex circuits; it can achieve high-density wiring and compact arrangement of components; it is easy to realize automated production and batch replication; it has good protection performance and can resist interference from the external environment.
  • Disadvantages: The design and production costs are relatively high, requiring professional knowledge and skills support; the production cycle is long, not suitable for rapid prototyping and temporary testing needs; once the production is completed, the circuit structure and component layout are not easy to modify.

3. Applicable scenarios:

  • Breadboard: suitable for beginners and small-scale prototyping, as well as temporary circuit testing.
  • PCB prototype: suitable for the design and production of complex circuits, as well as the needs of large-scale production and long-term stable operation.

What are the three types of breadboards?

Breadboards are mainly of the following three types: solderless breadboard, single breadboard and combination breadboard.

  • Solderless breadboard: This breadboard has no soldered power socket, is small in size, easy to carry, and is suitable for small circuit experiments. Its disadvantage is that the power connection is inconvenient and not suitable for large-scale circuit experiments.
How to use a pcb prototype board?
  • Single breadboard: Single breadboard is small in size, easy to carry, and can be easily turned on and off. But its disadvantage is that it is small in area and not suitable for large-scale circuit experiments.
  • Combination breadboard: Combination breadboard is to fix multiple solderless breadboards on the motherboard, and connect the power lines of each board together through the copper foil in the motherboard.

The use of PCB prototype board covers several key steps such as preparation, inspection, layout welding, testing and debugging, and maintenance and preservation. As a professional PCB manufacturer, BEST Technology has rich practical experience in the design and development of PCB prototypes. From the precise drawing of the schematic to the high-quality prototype production, every link is strictly controlled to ensure the provision of excellent performance, stable and reliable PCB prototypes.

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Is rf assembly high frequency or low frequency?
Thursday, December 19th, 2024

Is rf assembly high frequency or low frequency?RF components have a wide operating frequency range, covering multiple frequency bands from low frequency to high frequency. Generally speaking, the RF band generally refers to 3kHz to 300GHz, but in actual applications, 3kHz to 30MHz is often regarded as a low-frequency RF range, such as some simple wireless remote controls, while 30MHz to 300GHz belongs to high-frequency RF.

What is high-frequency vs low frequency?

Definition of high frequency and low frequency

  • Low-frequency circuit: mainly used to process signals with lower frequencies, usually in the range of tens of hertz to several thousand hertz. Common applications include audio circuits, etc.
Is rf assembly high frequency or low frequency?
  • High-frequency circuit: used to process signals with higher frequencies, usually in the range of several thousand hertz to several hundred megahertz. High-frequency circuits are very important in applications such as communications, radars, and satellites.

Differences between high frequency and low frequency in PCB design

  • Power supply design: In high-frequency PCB design, the power supply design is usually one layer, which can minimize signal loops and thus reduce noise.
  • Signal integrity: High-frequency PCB design requires special attention to signal integrity, including signal transmission delay, reflection and crosstalk.

Is RF high or low-frequency?

RF (radio frequency) is high frequency. It refers to the electromagnetic frequency that can be radiated into space. Its frequency range is from 300kHz to 30GHz, so it belongs to the high-frequency category. Alternating current that changes less than 1000 times per second is called low-frequency current, while alternating current that changes more than 10,000 times per second is called high-frequency current. RF is such a high-frequency current.

Basic characteristics of RF

  • Frequency and wavelength: The frequency of RF is between 300kHz and 30GHz. The wavelength is inversely proportional to the frequency, that is, the shorter the wavelength, the higher the frequency. The frequency of RF is higher, so the wavelength is shorter.
  • Amplitude and phase: The amplitude signal of RF represents the measure of the change of electric field oscillation, and the phase represents the position of a single time point in the wave cycle.
  • Modulation: In order to achieve communication, the RF signal needs to be modulated. Modulation includes analog modulation and digital modulation, which uses frequency, phase and amplitude to transmit data.

What is the highest RF frequency?

The highest frequency of RF (radio frequency) is 300GHz. Within this frequency range, RF is widely used in fields such as radar and wireless communication.

The basic characteristics of RF include frequency, wavelength, amplitude and phase. Frequency refers to the frequency of electromagnetic field oscillation, measured in Hertz (Hz). Wavelength is inversely proportional to frequency, that is, wavelength is equal to the speed of light divided by frequency. The amplitude of RF refers to the measure of the change in electric field oscillation, while the phase indicates the position of a single time point in the wave cycle.

How do you know if the frequency is high or low?

In PCB design, judging whether the frequency is high or low is mainly based on the frequency range of the signal.

Definition of frequency range

  • High frequency: usually refers to signals with frequencies between 3MHz and 300GHz. In PCB design, signals greater than 50MHz are generally considered high-speed signals, and signals with rising/falling edges less than 50ps are also considered high-speed signals.
Is rf assembly high frequency or low frequency?
  • Low frequency: usually refers to signals with frequencies between hundreds of Hz and hundreds of kHz.

Specific applications in PCB design

  • High-frequency PCB design: In high-frequency PCB design, the power supply design is usually one layer, which can minimize the signal loop and thus reduce noise. In addition, high-frequency signals are susceptible to interference, so special attention should be paid to noise issues in the design.
  • Low-frequency PCB design: Low-frequency circuit design usually does not need to consider signal loops and noise issues too much, but it is still necessary to pay attention to signal integrity and electromagnetic compatibility.

Measurement methods and tools

  • Oscilloscope: Oscilloscope is a common tool for measuring signal frequency. The frequency range of the signal can be judged by observing the waveform.
  • Spectrum analyzer: Spectrum analyzer can measure the frequency component of the signal more accurately and is suitable for occasions requiring high-precision measurement.

What is high-frequency PCB?

High-frequency PCB is a special type of circuit board designed specifically for processing high-frequency signals, and its operating frequency can reach hundreds of megahertz (MHz) to tens of gigahertz (GHz). High-frequency PCB occupies a key position in high-frequency application scenarios such as wireless communication, 5G, Wi-Fi, radar, and high-speed data transmission.

Is rf assembly high frequency or low frequency?

High-frequency PCB has a low dielectric constant, which leads to less signal loss during transmission. It is suitable for efficient transmission. It uses special materials to ensure a small dielectric constant, thereby ensuring transmission speed and meeting the needs of high-speed data transmission. In the field of precision metal material heating treatment, high-frequency PCB can achieve heating of components of different depths to meet various heating needs.

What is RF PCB?

RF PCB is a printed circuit board specially used for RF circuit design and manufacturing. It has unique characteristics and requirements in high-frequency signal transmission, impedance control, shielding and isolation, miniaturization and high-density wiring.

It is mainly used to process high-frequency signals, usually above 100MHz, and is widely used in wireless communications, radar systems and other application scenarios that need to receive and send wireless signals.

What is microwave PCB?

Microwave PCB (microwave printed circuit board) is a circuit board specially designed to process microwave frequency band signals. Microwave PCB usually works in microwave bands with a frequency greater than 2GHz. It uses a specific microwave substrate copper clad board and is produced through a special manufacturing process to meet the low-loss and low-delay transmission requirements of high-frequency signals. Its characteristics include:

Is rf assembly high frequency or low frequency?
  • Low loss: Microwave PCB uses materials with low dielectric constants to reduce energy loss during signal transmission.
  • High stability: stable performance in high temperature and high humidity environments, ensuring reliable signal transmission.
  • Low latency: suitable for high-speed data transmission needs, ensuring signal accuracy and stability.

The frequency range of RF components covers low frequency and high frequency, with unique characteristics and a wide range of application scenarios. As the key foundation for supporting the operation of high-frequency RF components, the characteristics and design of high-frequency PCB directly affect the performance of RF components. From signal integrity to system stability to miniaturization integration capabilities, they are inseparable from the careful design and optimization of high-frequency PCB.

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What is NPTH in PCB?
Wednesday, December 18th, 2024

What is NPTH in PCB? NPTH is a through hole on PCB, but unlike plated through hole, its hole wall is not treated with electroplated metal. These holes are usually used for mechanical installation, positioning or as non-electrical connection purposes such as ventilation and heat dissipation channels.

What is an NPTH?

NPTH refers to non-plated through hole, that is, a hole without electroplated metal on the hole wall. The hole wall of NPTH hole is not electroplated with metal and is usually used for positioning, fixing or as a screw hole. These holes do not participate in electrical connection and are mainly used for mechanical fixing or structural support.

What is NPTH in PCB?

NPTH holes are often used in the following scenarios:

  • Positioning hole: used to position and fix other components or parts on PCB.
  • Screw hole: used to install screws and fix PCB or other components.
  • Mounting hole: used to install connectors or other external devices.

What is the full form of NPTH?

The full name of NPTH is “Non Plating Through Hole”. In printed circuit boards (PCBs), NPTH refers to holes whose walls are not plated with metal and therefore do not participate in electrical connections. Such holes are usually used for positioning, fixing screws or other non-conductive purposes.

What is the difference between PTH and non PTH?

The main difference between PTH (Plating Through Hole) and NPTH (Non Plating Through Hole) is whether the hole wall is plated.

1. Plating:

  • PTH: The hole wall is plated and is usually used for electrical connections, such as vias (VIA) and component holes. There is copper on these hole walls, which can achieve electrical conduction between the layers of the circuit board.
  • NPTH: The hole wall is not plated and is usually used for positioning, fixing and other functions, such as screw holes or connector fixing holes. There is no copper in these hole walls and does not participate in electrical connections.

2. Appearance characteristics:

  • PTH: There are traces of plating, the hole wall is smooth and covered with copper.
  • NPTH: There are no traces of plating, the hole wall is not smooth and not covered with copper.

3. Application scenarios:

  • PTH: Mainly used in scenarios where electrical connection is required, such as connecting different layers of a circuit board or connecting components.
  • NPTH: Mainly used in scenarios where electrical connection is not required, NPTH holes usually do not have hole rings, but in some special cases, hole rings are also designed to achieve grounding functions.

What is a PTH pad?

PTH pads (Plated Through Hole) refer to pads with through holes, and the hole walls are copper-plated. PTH pads play an important role in PCB design, and are mainly used to connect different layers of a circuit board or connect component pins to a circuit board.

The following points should be noted during the design and manufacturing process of PTH pads:

  • Size and shape: The outer ring of the PTH pad cannot be less than 0.2mm (8mil) on one side to ensure stability during welding.
  • Welding process: During welding, the PTH pad will take away a considerable amount of solder, which may cause insufficient solder problems.
  • Manufacturing capability: The design of the PTH pad is directly related to the manufacturing capability of the circuit board, which may cause welding quality problems.

PTH pads play a key role in PCB assembly, ensuring stable connection of components and reliable electrical performance. Correct PTH pad design can significantly improve the reliability and manufacturing quality of the circuit board.

How thick is plated through-hole plating?

The plating thickness standards for plated through-holes vary depending on the application scenario. Specifically:

  • IPC Level 1: The smallest thickness, short service life, usually used in consumer electronics that may become obsolete in a few years, requires an average thickness of 20 microns, and spots are not thinner than 18 microns.
  • IPC Level 2: More durable, continuously used holes, suitable for equipment that often runs for 5 years or more, requires an average thickness of 20 microns, and spots are not thinner than 18 microns.
  • IPC Level 3: The thickest and most durable plated through-holes, used for products expected to be used for ten years or more, requires an average thickness of 25 microns, and spots are not thinner than 20 microns.

What is the anatomy of a plated through-hole?

A plated through-hole (PTH) is a hole drilled in a circuit board, and a layer of metal is deposited on the hole wall through an electroplating process to achieve electrical connections between different layers of the circuit board. Its construction usually includes the following parts:

  • Hole wall: The hole wall of the plated through-hole is formed by drilling, usually in a circular or other shape.
  • Metal plating: A layer of metal deposited on the hole wall by electroplating process to achieve electrical connection. The thickness and quality of the metal plating have an important impact on the electrical performance and reliability of the plated through-hole.
  • Pad: Located at both ends of the plated through-hole, it is used to solder electronic components or connect other circuit boards. The shape and size of the pad are usually designed according to the type and size of the electronic component.
  • Solder mask: A layer of insulating material covering the surface of the circuit board to prevent solder flow and short circuit during soldering. The solder mask usually leaves a certain opening around the plated through-hole to solder electronic components.

What is the required hole fill of a plated through-hole?

The required hole fill of a plated through-hole is usually required to reach 100%. Specifically, the plated through-hole (PTH) should be filled with 100% vertical solder, the solder side should have a perfect fillet, and the component and pad should be in 100% contact with the solder.

The surface of the weld should be smooth, non-porous, non-disturbed, bright, and the solder joints completely wrap the solder feet and are concave. In addition, electroplating hole filling technology also plays an important role in improving the electrical performance and connection reliability of circuit boards.

What is NPTH in PCB?

Electroplating hole filling can improve electrical performance, improve connection reliability, avoid electromagnetic interference, and has excellent solderability and a more simplified process. In practical applications, electroplating hole filling is suitable for blind holes with a diameter of 80-220um and a thickness-diameter ratio of less than or equal to 1:1. The hole filling rate can reach more than 85%.

What is the difference between plated and coated?

The main difference between plating and coating lies in their formation method and application scenarios.

1. Formation method

  • Plating: Plating is a metal protective layer formed on the surface of the material by electroplating or chemical plating. Electroplating is to use the principle of electrolysis to plate a thin layer of other metals or alloys on certain metal surfaces to form a metal film. Chemical plating is to form a metal coating on the surface of the material through chemical reaction.
  • Coating: Coating is a protective layer formed by spraying paint on the surface of the material. Common coating methods include hot-dip galvanizing, thermal spraying and surfacing, which mainly apply metal to the surface of the substrate by physical means.

2. Application scenarios

  • Plating: Plating is widely used in aviation, automobile, electronics and other fields. In the aviation field, coating can improve the mechanical strength and processing accuracy of parts and reduce the weight of parts; in the automotive field, coating can improve the corrosion resistance and wear resistance of the car body.
  • Coating: Coating is widely used in construction, machinery, automobile and other fields. In the construction field, coating mainly plays the role of anti-corrosion, waterproof, heat preservation, etc.; in the mechanical field, coating can enhance the hardness, wear resistance and corrosion resistance of the material surface.

3. Advantages and disadvantages

  • Plating: Advantages include good anti-corrosion, anti-wear, electrical conductivity, thermal conductivity and aesthetics. Disadvantages are complex process and high cost.
  • Coating: Advantages are simple process, low cost, anti-corrosion, waterproof, wear resistance, heat insulation and other characteristics. Disadvantages are that the aesthetics and some physical properties are not as good as plating.

Although NPTH in PCB does not directly participate in electrical connection like plated through holes, it plays an irreplaceable role in mechanical installation, heat dissipation, etc., and together with plated through holes, it constitutes a complete functional system of PCB.

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What are PCB stencil printers?
Wednesday, December 18th, 2024

What are PCB stencil printers? stencil pcb printers is a process for applying solder paste to specific pad locations on a PCB board with high precision. The core tool is the PCB stencil, a thin sheet of precision-machined metal with holes that exactly match the shape, size, and location of the PCB board pads.

What is a PCB stencil?

A stencil in PCB refers to a tool used in the surface mount assembly process to precisely deposit solder paste at specific locations on a printed circuit board. The stencil is usually made of brass or stainless steel and is engraved with circuit patterns that match the locations of surface mount devices (SMDs) on the PCB.

What are PCB stencil printers?

The stencil plays a vital role in the PCB assembly process. It ensures that solder paste is accurately deposited at the locations of the SMDs, thereby ensuring that the components are accurately mounted in the correct locations.

The design of the stencil, including its composition, thickness, and the shape and size of the holes, will affect the quality of the solder paste deposition. Too much or too little solder paste can lead to welding quality problems, such as ball formation, bridging or tombstoning.

What is a PCB stencil made of?

PCB stencils are mainly made of stainless steel, which has good corrosion resistance and high hardness. This stencil is usually called a SMT Stencil or a solder paste printing stencil, which is mainly used to print solder paste onto PCB circuit boards during SMT assembly.

The stencil is cut by high-precision laser, and has holes or grooves corresponding to the PCB pads, which are used to accurately control the printing of solder paste.

What types of PCB stencils are there?

The types of stencil in PCB stencils mainly include the following:

  • AI stencil: mainly used in SMT process, can replace dispensing machines, improve production efficiency and reduce costs.
What are PCB stencil printers?
  • Laser stencil: through high-energy laser cutting to create an opening that perfectly matches the PCB pad, it has the advantages of high precision and smooth edges, and is particularly suitable for high-density and high-demand PCB assembly.
  • Etched stencil: The opening is formed by chemical etching liquid corroding the steel sheet. The cost is lower, but the accuracy and edge smoothness are not as good as laser cutting.

These stencil types have their own characteristics and are suitable for different PCB manufacturing needs. Laser stencils are particularly suitable for high-density and high-demand PCB assembly due to their high precision and smooth edges; while etched stencils are suitable for applications with low precision requirements due to their low cost and simple manufacturing process.

What is the function of a PCB stencil?

The stencil in the PCB template plays a vital role in the manufacturing process. The stencil is a high-strength metal grid that is mainly used to apply solder paste on the PCB. Its specific functions include:

  • Accurate quantitative distribution of solder paste: The stencil accurately controls the distribution of solder paste through the holes on it, ensuring that the solder paste is evenly and accurately applied to the predetermined pad position on the PCB, avoiding too much or too little solder paste, thereby ensuring welding quality.
  • Improve welding quality: By precisely controlling the distribution of solder paste, stencil helps reduce welding defects such as bridging and empty soldering, improves the consistency and reliability of welding, and thus improves the electrical performance of the entire PCB and the overall quality of the product.
  • Adapt to complex designs: With the trend of miniaturization and high density of electronic products, the components on PCBs are getting smaller and smaller, and the spacing is getting closer and closer. Stencil can be customized according to design requirements to meet the needs of high-end electronic products.
  • Improve production efficiency: On an automated production line, with the use of precision stencil and automatic solder paste printers, fast and efficient mass production can be achieved, greatly improving production efficiency and reducing the error rate of manual operation.

How to design a PCB stencil?

In the surface mount (SMT) assembly process, solder paste stencil plays a key role. Its ability to accurately apply solder paste is directly related to the quality and reliability of the connection between SMD components and PCB pads. The following are the key points to focus on when designing solder paste stencils:

  • Matching design files: The design of solder paste stencils must be closely constructed based on the solder paste layer information of the PCB to ensure that every hole and shape on the stencil is precisely matched with the solder paste layer, so as to provide an accurate basis for subsequent solder paste coating and avoid poor welding problems caused by design deviations.
  • Selection and thickness: There are many types of solder paste stencils, the most common of which are stainless steel stencils and polymer stencils. At the same time, the determination of stencil thickness cannot be ignored. It is usually in the range of tens to hundreds of microns. It needs to be finely adjusted in combination with factors such as pad size, pin spacing, and required solder paste amount to ensure uniformity and stability of solder paste coating.
What are PCB stencil printers?
  • Hole size and shape: The hole size and shape of the stencil should be perfectly matched with the solder paste area on the solder paste layer, and the solder paste coating range should be strictly controlled to prevent the solder paste from overflowing to the adjacent pads and causing short circuit failures, or insufficient solder paste coating affecting the welding quality, to ensure that the solder paste coating is accurate at every location.
  • Customized special design: For special components or parts with special pin structures, a special design scheme is required on the solder paste stencil.

How to use a PCB stencil?

The following are the steps to use a PCB stencil:

1. Preparation:

  • Check whether the PCB stencil opening is blocked or deformed, and whether the PCB board surface is clean.
  • According to the size of the printer and the stencil, install the stencil through the positioning hole and the printer positioning pin to ensure the correct direction and secure fixation.
What are PCB stencil printers?

2. Solder paste preparation:

  • Select solder paste according to PCB welding requirements and component type, check the shelf life and quality, take it out and stir it for 3-5 minutes to make it uniform.

3. Solder paste printing:

  • According to the thickness of the stencil, opening and solder paste characteristics, adjust the parameters such as the printer scraper pressure, printing speed), demolding speed and stroke.
  • Start the printer, and the scraper moves to fill the stencil opening with solder paste and transfer it to the PCB pad. Observe the printing situation during the process and adjust it in time if there is any problem.

4. Post-printing inspection and cleaning:

  • Use a magnifying glass or SPI to check the quality of solder paste printing on the PCB board, and reprint the unqualified ones after cleaning.
  • Use special solvents and tools to clean the template, remove the residual solder paste, and store it properly after drying.

PCB stencil printing is an indispensable key process in the field of electronic manufacturing. As a core tool, the quality and precision of the stencil directly determine the coating effect of the solder paste on the PCB board, which in turn affects the welding quality of electronic components, and ultimately plays a decisive role in the performance, reliability and stability of electronic products.

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Mastering circuit teensy diagram maker for easy design
Tuesday, December 17th, 2024

Mastering circuit teensy diagram maker for easy design, circuit diagram maker is a software or online tool. It has a rich electronic component symbol library, allowing users to place components by simple drag and drop operations, and can also use wiring tools to depict the connection relationship between components to make circuit schematics. For PCB circuit diagrams, it can reasonably layout components, set different line widths and spacing, and can also perform electrical and design rule checks, and output files in multiple formats. It is an important tool for circuit diagram production in the field of electronic design.

Mastering circuit teensy diagram maker for easy design

How do you make a simple circuit diagram?

The following are the steps to make a simple PCB circuit diagram:

1. Circuit design planning:

  • Clarify the purpose and performance of the PCB, and determine parameters such as power supply voltage, current, and signal frequency.
  • Select components based on function, and check the data sheet to determine the package, pins, and electrical parameters.

2. Draw a schematic:

  • Select EDA software (such as Altium Designer, Eagle, KiCad, etc.) or draw it manually with pencil and graph paper (need to be converted to electronic format).
  • In the software, find symbols from the component library and drag and drop them, or manually draw component symbols according to the standard and mark the names.
  • Use the software to connect component pins with a wiring tool, and manually use a ruler and pencil to connect. Pay attention to the connection point representation and neat lines.
  • Mark component parameters, names, packages, and network names or signal names.

3. PCB layout:

  • Create a new PCB file and import schematic information.
  • Determine the PCB size and shape according to requirements, such as selecting a 50mm×50mm square.
  • Drag and drop components from the library into the board frame, divide them according to function, and pay attention to the spacing that is conducive to welding and heat dissipation, such as separating high-power components.

4. PCB wiring:

  • Set wiring rules according to circuit properties and component parameters, such as power line width 1-2mm, signal line width 0.2-0.5mm, and spacing not less than 0.2mm.
  • Manual wiring (using software wiring tools to draw lines according to connection relationships and control the direction), automatic wiring (manual adjustment after the software automatically completes) or a combination of the two.
  • Check whether the wiring is compliant, whether there are short circuits or open circuits, optimize the wiring of key signals, and reduce interference.

5. Design inspection and output files:

  • Use the software DRC function to check the PCB design and modify the problems according to the prompts.
  • Generate Gerber files (for PCB manufacturing) and BOM files (list component information). Different software has different generation methods, such as “File”-“Fabrication Outputs” in Altium Designer to generate Gerber, and “Reports”-“Bill of Materials” to generate BOM.

What is a circuit board diagram called?

Circuit board diagrams are usually called PCB diagrams (printed circuit board diagrams). Concepts related to PCB diagrams include schematic diagrams, block diagrams, and assembly diagrams.

PCB diagrams are detailed layout diagrams of circuit boards, which accurately show the location of components on the circuit board and the routing of the circuit. Through the PCB diagram, you can clearly understand the location of circuit components on the PCB, the connection method, and the circuit direction, thereby ensuring the correctness and reliability of the circuit.

Mastering circuit teensy diagram maker for easy design

PCB diagrams play a vital role in the manufacturing and assembly process of electronic equipment. It guides the layout and connection of electronic components to ensure that the physical construction and assembly of the circuit are correct. The unnecessary copper foil is removed chemically or mechanically to form the path of the circuit, and then the electronic components are installed on the circuit board to form a complete circuit.

Which software is used for PCB designing?

Commonly used software for designing PCBs include Altium Designer, Cadence Allegro and Mentor Graphics PADS PCB.

1. Altium Designer

Altium Designer is a world-renowned PCB design software that supports the entire process from schematic design to PCB layout. It has a wealth of library components, powerful automatic routing functions and a variety of export functions, which can help designers complete the design quickly and efficiently.

2. Cadence Allegro

Cadence Allegro is a commercial EDA software with very rich functions. It provides control over the components and PCB software used in electronic systems to ensure the smooth implementation of the project. Allegro has a number of technologies such as three-dimensional electronic design and simulation, printed circuit board design, hardware description language, etc., which can control the workflow more finely.

3. Mentor Graphics PADS PCB

PADS PCB is a PCB design software developed by Mentor Graphics, which is widely used in communications, automobiles, medical and other fields. It provides a clear and intuitive user interface and powerful library component management functions, making the PCB design process simpler and more convenient. PADS PCB supports fully automatic routing and signal integrity analysis, effectively improving design quality and efficiency.

How do you draw a PCB layout?

1. Preparation

  • Complete the schematic design and check the component connections and parameters.
  • Be familiar with the component package and check the appearance, pin distribution and other information.
  • Determine the PCB size and shape according to the application scenario and installation requirements.
Mastering circuit teensy diagram maker for easy design

2. Layout principles

  • Place components according to functional partitions for easy debugging and maintenance.
  • Arrange components according to signal flow to avoid line bending and crossing.
  • Ensure component spacing and consider installation requirements.

3. Start layout

  • Import the schematic information into the PCB design software.
  • Place components manually and arrange them neatly using software tools.
  • Adjust component positions, considering signals, routing and electromagnetic interference.

4. Check and optimize the layout

  • Check whether it complies with the layout principles and design rules.
  • Optimize the layout to facilitate wiring, considering multi-layer PCBs and high-frequency signals.

What does j mean on a circuit board?

The “J” on the circuit board usually stands for a socket (Connector). In circuit board design, the letter “J” is often used to represent various types of connectors or sockets for connecting different circuit boards or external devices. In addition, “J” sometimes also stands for a jumper (Jumper), which is used to temporarily connect two nodes.

What is k in a circuit diagram?

The letter “K” in a circuit diagram usually represents components such as relays and contactors. In a circuit diagram, the letter “K” can represent a variety of electrical components, including relays (KA), contactors (KM), time relays (KT), frequency relays (KF), pressure relays (KP), signal relays (KS), grounding relays (KE), etc. In addition, “K” can also represent emergency stop switches (KS).

These components play different roles in the circuit:

  • Relay: used to automatically control the on and off of the circuit.
  • Contactor: used to frequently connect and disconnect high-current circuits.
  • Time relay: used to connect or disconnect circuits after a specific time.
  • Frequency relay: used to detect and control frequency signals.
  • Pressure relay: used to detect and control pressure signals.
  • Signal relay: used to transmit and control signals.
  • Grounding relay: used for grounding protection.

These components play an important role in circuit design and maintenance. Understanding their symbols and functions helps to better understand and maintain circuit systems.

What is the difference between a schematic diagram and a circuit diagram?

The main difference between a schematic diagram and a circuit diagram is that they focus on different focuses and usage scenarios.

1. Definition and function

  • Schematic diagram: A schematic diagram is a graphical representation that is mainly used to represent the logical and functional relationship between components in an electronic device or system. It uses symbols and connecting lines to represent electronic components and signal transmission paths, without involving specific physical layouts and sizes.
Mastering circuit teensy diagram maker for easy design
  • Circuit diagram: Circuit diagrams focus more on electrical connections and physical layouts, and are used to show the physical connections and relative positions between components in an electronic device or system. Circuit diagrams use symbols and connecting lines to represent electrical connections, emphasizing electrical connections and physical layout rather than just signal transmission.

2. Usage scenarios

  • Schematic diagrams: Mainly used in the design and analysis stages of electronic systems. Designers use schematic diagrams to describe the logic and functions of electronic devices or systems for analysis and optimization during the design stage.
  • Circuit diagrams: Mainly used in the manufacturing, maintenance and testing stages of electronic systems. Technicians use circuit diagrams to plan physical layouts and electrical connections, and visualize the structure and function of circuits before actually assembling and installing electronic devices.

3. Specific application examples

  • Schematic diagrams: In the design stage, designers use schematic diagrams to describe the overall architecture and workflow of the system to ensure that the logical relationship between the components is correct.
  • Circuit diagrams: In the manufacturing, maintenance and testing stages, technicians use circuit diagrams for actual circuit connections and troubleshooting.

In general, circuit teensy diagram maker is an indispensable key tool in the field of modern electronic design. Through efficient design processes, precise component layout and wiring functions, and strict rule checking mechanisms, they provide solid technical support for the research and development, manufacturing and innovation of electronic products, making complex circuit design work more efficient, accurate and reliable.

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How are the circuit boards connected?
Tuesday, December 17th, 2024

How are the circuit boards connected? Soldering is the most common and long-standing way to connect circuit boards. For traditional circuit boards, we usually use electric soldering irons to perform soldering operations. First, the metal part of the electronic component pins or wires to be connected is tightly fitted with the corresponding pads on the circuit board. Then, the pads and pins are heated with an electric soldering iron, and the solder wire is brought close together to melt the solder and evenly wrap the connection parts to form a stable metal connection.

How are the circuit boards connected?

A circuit board 6 connections typically refers to a design that incorporates six distinct points or pads for electrical connections, which could be input/output ports, signal pathways, or power connections. These boards are often used in simple applications where a limited number of connections are needed to interface with other components or systems.

What are the connections between circuit boards?

The main ways to connect circuit boards include the following:

  • Welding connection: This is one of the most commonly used connection methods, which connects components on the circuit board together by welding. The advantages of welding connection are stable and reliable connection, low cost, and suitable for circuit boards that do not require regular changes.
  • Plug-in connection: Plug-in connection can achieve fast plug-in and pull-out, easy replacement and maintenance, but requires high precision of plug-ins and sockets, and occupies a large space, which is not suitable for circuit boards with limited space.
  • Connector connection: This is a widely used circuit board connection method that can connect circuit boards of different forms and sizes. The advantages of connectors are convenient and fast connection, high reliability, and a large number of plug-in and unplug times, which are suitable for various circuit board application scenarios.
  • Plug-in connection: widely used in complex instruments and equipment, and connected through standard pins or sockets. This method is easy to replace and repair, ensuring the reliability and production efficiency of the connection.
  • Special connection methods: including V-cut and copper foil bridge connection, spring connection and spring connection, panel connection, etc. These methods are suitable for specific scenarios and needs, such as V-cut for the separation stage of PCB boards, spring connection and spring connection for the connection of flexible circuit boards, and panel connection for multiple PCB designs placed on a large substrate.

How to connect components on PCB?

There are usually the following ways to connect components on PCB:

  • Soldering: This is the most common connection method. By connecting the pins of the components to the pads on the PCB with solder, you can use a soldering iron or SMT equipment for soldering.
  • Spring contact: For some components that need to be replaced frequently, such as batteries, you can use spring contact to make the components easy to disassemble.
How are the circuit boards connected?
  • Screw fixing: For components that need to withstand large forces, such as heat sinks, motors, etc., screw fixing can be used. Pay attention to choosing the right screws and tightening strength.
  • Clamping with pliers: For some components that need to be fine-tuned, such as rheostats, potentiometers, etc., pliers can be used to clamp.
  • Plastic bayonet: For some components that need to be frequently plugged and unplugged, such as wire connectors, plastic bayonet can be used for connection.

How to connect PCB boards together?

To connect PCB boards together, you can consider the following common methods:

Welding:

  • PCB wire welding: This is a simple and commonly used method to achieve connection by directly welding the wire to the pad of the PCB board. When welding, you need to pay attention to the quality and stability of the welding to ensure the reliability of the connection.
  • PCB cable welding: It is suitable for situations where multiple wires need to be connected. You can use cable to connect multiple PCB boards together, and then fix the connection between the cable and the PCB board by welding.
  • Direct welding between PCBs: This method is often used for connections between two PCB boards at a 90-degree angle. When welding, attention should be paid to the alignment and fixation between the two PCB boards to ensure the quality of welding.

Plug-in connection:

  • Printed circuit board socket: This connection method is often used in more complex instruments and equipment. A printed plug is made from the edge of the PCB board. The plug part is designed according to the size of the socket, the number of contacts, the distance between contacts, the position of the positioning holes, etc., so that it matches the dedicated PCB printed circuit board socket.
How are the circuit boards connected?
  • Standard pin connection: This method is suitable for use in small instruments. Two PCB boards are connected by standard pins. The two PCB boards are generally parallel or vertical.
  • Crimping: The PCB board is crimped with other components through a special crimping tool to achieve connection. This method is suitable for situations where frequent disassembly and replacement are required.
  • Bonding: Use glue or adhesive to bond the PCB board with other components. This method is suitable for situations where the connection strength requirement is not high.
  • Use connectors: Connectors are a component specially used to connect PCB boards, which can provide reliable connection and convenient disassembly. There are many types of connectors, and you can choose the right connector according to specific needs.
  • Screw fixing: For some larger or heavier PCB boards, screws can be used to fix them to other components to ensure the stability of the connection.

What are the different types of PCB connectors?

The main types of PCB connectors include the following categories:

  • Ordinary board-to-board connector: used to connect two parallel or vertical PCBs, suitable for signal transmission between different circuit boards. According to different spacing, it can be divided into 0.50mm, 0.60mm, 0.80mm and other specifications. The smaller the spacing, the more pins can be accommodated, and the signal transmission is more intensive, but the processing accuracy and installation requirements are higher.
  • Mezzanine connector: mainly used to connect two PCBs with close spacing when space is limited. It is usually connected in a stacked manner to save space and is often used in the connection structure of the motherboard-daughterboard.
  • Backplane connector: a group of electrical connectors parallel to each other, each pin of each connector is connected to the same relative pin of all other connectors to form a connector bus.
  • Spring-type board-to-board connector: contains a spring structure inside, which can ensure a stable connection even when the spacing between the boards fluctuates. It is suitable for devices with high requirements for connection stability.
  • Wire-to-board connector: used to connect wires or cables to PCBs. The wire connection part is similar to the wire-to-wire connector, while the circuit board connection part is mostly a two-piece connector that is press-fit or welded.
  • Wire-to-wire connector: used to connect two wires. One end of the connector is permanently connected to the wire, and the other end forms a detachable interface. Permanent connection methods can use crimping or insulation displacement contacts (IDC), etc.

How to choose PCB connectors?

There are several key factors to consider when choosing PCB connectors:

  • Connector type: choose the appropriate connector type according to application requirements.
  • Size: The size of the connector needs to adapt to the size and layout of the circuit board to ensure that the connector can be properly installed and connected.
How are the circuit boards connected?
  • Electrical performance: consider the rated voltage, rated current, and withstand voltage of the connector to ensure that it can withstand the electrical load required by the device.
  • Mechanical performance: includes the number of plug-in and unplugging times, durability, and shock resistance. If the device needs to frequently plug and unplug the connector, a durable and long-life connector should be selected; if the device will be subject to vibration or shock, a connector with good shock resistance should be selected.
  • Environmental conditions: Environmental conditions have a great impact on the choice of connectors.
  • Technical parameters: Understand the technical requirements of the application, including pin spacing, soldering method, rated voltage, rated current, number of plug-in and unplug times, temperature range, board spacing, connector geometry, and solder hole diameter of the solder tab.

How do you connect wire to a circuit board?

Soldering is usually used to connect wires to circuit boards. Solder the ends of the wires to the pads on the circuit board using a soldering iron and solder.

  • Prepare tools and materials: soldering iron, solder wire, flux, wires, and circuit boards.
  • Clean wires and circuit boards: Use alcohol or other cleaning agents to clean the wires and pads on the circuit board to ensure a good solder connection.
  • Strip the wire: Use wire strippers or scissors to strip a section of the wire end to expose the metal wire inside.
  • Tin the wire: Place the end of the wire on the soldering iron tip and wrap it with solder wire at the same time to evenly coat the end of the wire with a layer of solder.
  • Solder wires to circuit boards: Place the tinned wire ends on the pads on the circuit board, and use a soldering iron to melt the solder to connect the wires to the pads.
  • Check welding quality: Check whether the solder joints are firm and whether there are problems such as cold solder joints or short circuits.
  • Clean the soldering area: Use alcohol or other detergents to clean the soldering area to remove excess solder and flux.

Circuit board connection is a technology that requires both theoretical knowledge and practical experience. From basic soldering and plug-in connections to various unique ways of PCB connection, each connection method has its applicable scenarios and key points. Regardless of the connection method, preparation before connection, detailed control during the connection process, and detection and debugging after connection are all crucial.

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What is solder paste inspection?
Monday, December 16th, 2024

What is solder paste inspection? In simple terms, solder paste inspection is the process of inspecting and evaluating the quality, volume, shape, position and other parameters of solder paste printed on PCB. As the key material for connecting electronic components to PCB, the quality of solder paste printing directly determines the quality of soldering, which in turn affects the electrical and mechanical properties of PCBA.

How does solder paste inspection work?

The working principle of SPI solder paste inspection equipment is mainly based on optical principles and laser triangulation technology. The equipment irradiates the soldering surface through a camera and a light source to obtain an image of the solder paste, and then detects and analyzes the shape, size, position, etc. of the solder paste through image processing technology to determine the quality of the solder paste and the welding effect.

What is solder paste inspection?

Specifically, when the solder paste is scanned by a laser, the laser emits a laser, which is reflected and focused by the lens to irradiate the laser onto the solder paste. Due to the reflection of the solder paste, a part of the laser is reflected back and captured by the camera. By calculating the time difference between laser emission and reception, parameters such as the height and area of ​​the solder paste can be determined.

Specific steps and principles of SPI solder paste detection

  • Image acquisition: Use a high-definition camera and light source to take pictures of the solder paste on the pad on the PCB surface to collect images.
  • Image processing: Analyze and calculate the shape, size, position and other parameters of the solder paste through image processing algorithms, and compare them with previous standard data.
  • Defect detection: Through comparative analysis, it is determined whether the printing has defects, such as solder paste offset, unevenness, less tin or more tin, etc.

Advantages of SPI solder paste detection

  • Reduce the unqualified rate: The introduction of SPI can effectively reduce the unqualified rate of the original finished PCB by more than 85%, and significantly reduce the cost of rework and scrap by more than 90%.
  • Improve the pass rate: Used in conjunction with AOI, through real-time feedback and optimization of the SMT patch proofing production line, the production quality can be more stable, and the unstable trial production stage that must be experienced when introducing new products can be greatly shortened.
  • Make up for the shortcomings of traditional inspection: 3D inspection effectively makes up for the shortcomings of traditional inspection methods, especially for the inspection of micro components.
  • Reduce bad situations: Through process control, minimize the bad situations of components after the furnace.
  • Ensure printing quality: It can effectively ensure good solder paste printing quality and greatly reduce the possible defective rate of finished products.

What does solder paste inspection do?

Solder paste inspection has the following main functions:

  • Ensure welding quality: The amount and shape of solder paste directly affect the welding effect. Through inspection, it can ensure that the amount of solder paste is moderate, avoid short circuits caused by too much solder paste, or problems such as cold soldering and open circuits caused by too little solder paste, thereby improving the reliability of solder joints and the electrical performance of products.
  • Optimize the production process: Solder paste inspection can promptly detect problems in the solder paste printing process, such as printing position offset, tinning, etc. This helps to adjust and calibrate the printing equipment, make the printing process more accurate and stable, and improve production efficiency.
What is solder paste inspection?
  • Ensure product consistency: When mass-producing electronic products, solder paste inspection can ensure that the solder paste state on each circuit board is relatively consistent. This can keep the product’s soldering quality at a stable level, reduce product quality fluctuations, and improve the overall quality and consistency of the product.

How to measure solder paste height?

In SMT (surface mount technology), there are several main methods for measuring solder paste height:

  • Laser scanning method: Using the principle of laser triangulation, the laser beam scans the solder paste surface and calculates the solder paste height by the angle change of the reflected light.
  • Microscope method: By adjusting the focal length of the microscope, the focal plane coincides with the solder paste surface, and the height information at this time is measured using the optical system.
  • Mechanical contact measurement method: Use a measuring instrument with a high-precision probe to contact the solder paste surface through the probe, and convert the displacement into an electrical signal to determine the solder paste height.

What does AOI mean in inspection?

AOI is automatic optical inspection, which uses cameras and optical components to obtain images of the PCB of the object being inspected, and then analyzes these images through image processing algorithms. These algorithms compare the actual image with the pre-set standard image or rules to identify various features on the surface of the object, such as the position, shape, size of the component, and whether the quality of the solder joint meets the requirements.

Principle and process of AOI detection

  • Image acquisition: The AOI detection system collects image data on the surface of the product through a camera or sensor, including various details, components and connecting parts.
  • Image processing: The received image data is processed by an image processing algorithm to remove interference, enhance image quality, and extract key information for subsequent analysis.
  • Defect identification: Using pre-set models and rules, key features in the image are compared and analyzed to identify defects, misalignment or missing problems on the surface of the product.
  • Alarm and classification: Once an abnormality is found, the AOI system will trigger an alarm mechanism and classify the defect type for subsequent processing and repair.

AOI detection systems are widely used in electronic manufacturing, printing industry and other fields. In electronic assembly production lines, it is used to detect PCB boards, solder joints, component positions, etc. to ensure product quality and reliability.

What is the difference between AOI and SPI?

AOI (Automated Optical Inspection) and SPI (Solder Paste Inspection) have the following main differences in SMT (Surface Mount Technology) processing:

1. Different inspection objects:

  • AOI mainly inspects components and solder joints during SMT processing, and detects common errors such as component misalignment, reversal, missing, and redundant, as well as defects after soldering such as cold soldering and bridging.
  • SPI focuses on the quality assessment of solder paste printing. By measuring the volume, area, height and other parameters of solder paste, it evaluates the printing quality of solder paste and ensures the correct printing of solder paste.
What is solder paste inspection?

2. Different inspection principles:

  • AOI uses optical principles to analyze images on circuit boards and identifies defects through image processing algorithms. It uses a high-resolution camera to capture images of PCBAs and compares them with preset standard templates.
  • SPI evaluates the printing quality of solder paste by measuring various parameters of solder paste, and uses 3D imaging technology to capture the three-dimensional shape of solder paste and compares it with standard data.

3. Different detection timing:

  • AOI usually performs detection after component placement and welding. It can detect multiple welding points at one time after welding. The detection speed is fast and the impact on production efficiency is relatively small.
  • SPI performs detection immediately after solder paste printing. Since it needs to be detected immediately after solder paste printing, it has a greater impact on production efficiency.

4. Application scenarios and advantages:

  • AOI is suitable for high-demand SMT processing production lines. It can quickly and accurately detect a variety of defects and ensure the quality stability of circuit boards.
  • SPI is crucial to ensure the quality of solder paste printing, directly affects the subsequent placement and welding effects of components, and is suitable for production lines that require high-precision solder paste printing.

What are the defects of SPI?

The defects of 3D SPI (Surface Inspection) mainly include the following aspects:

  • Low laser resolution: The laser resolution of 3D SPI is generally at the level of 10-20um, which may not be ideal for precise circuit board detection.
  • Repeatability accuracy is affected: Since each sampling can only provide information of one point, the repeatability accuracy of 3D SPI may be affected.
What is solder paste inspection?
  • Sensitive to external vibration: External vibration has a great impact on the detection effect of 3D SPI, and additional stabilization measures may be required to ensure the accuracy of the detection.
  • Light conditions: The equipment relies on the principle of optical imaging for detection, so it has high requirements for the light conditions of the detection environment and needs to work under stable and uniform lighting conditions to ensure image quality and detection accuracy.
  • Relatively slow speed: Compared with some other detection technologies, 3D SPI may be slower.

How long can solder paste sit before reflow?

Before the reflow process, the solder paste needs to stay for a period of time to adapt to the environment and ensure the reliability and quality of the solder joints. The optimal dwell time is affected by various factors, such as the freshness of the solder paste, recycled solder paste, ambient temperature and humidity.

The length of the dwell time directly affects the viscosity and fluidity of the solder paste, thereby determining the solder joint morphology and reliability. If the dwell time is too short, there may be gaps and cracks in the solder joint, which affects its reliability. If the dwell time is too long, the surface tension of the solder joint will increase, resulting in irregular morphology on the solder joint surface, which affects the power-on performance of the circuit.

In general, the best dwell time is between 4 and 8 hours. It should be noted that too long or too short a dwell time will affect the solder joint morphology and reliability. Therefore, in specific applications, it is necessary to select the best solder paste dwell time according to actual conditions.

In short, solder paste detection, as a key link in PCBA production, plays a vital role in ensuring the quality and performance of electronic products. Its detection methods cover visual inspection, 2D detection, and advanced 3D detection, each with its own advantages and disadvantages and applicable scenarios, and is a key line of defense to ensure the quality and performance of electronic products.

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What does pwb meaning?
Monday, December 16th, 2024

What does pwb meaning? PWB is the abbreviation of Printed Wiring Board. It originated from the need for electronic component connection carriers in the early development of electronic technology. Early electronic devices were relatively simple, and the electrical connection between electronic components was mainly achieved by printing metal circuits on insulating substrates. These circuits are like precise “roads” that guide the current to be transmitted between components, so that electronic devices can work properly.

What does pwb meaning?

What does the term PWB mean?

PWB refers to Printed Wiring Board, which is a carrier that uses conductors on an insulating substrate to form interconnected circuits between devices. PWB is an important component of electronic equipment and is used to achieve electrical connections between electronic components.

In the field of electronic manufacturing, PCB (Printed Circuit Board) and PWB (Printed Wiring Board) have a close connection and a specific historical evolution. Today, in most parts of the world, PCB and PWB actually refer to the same item, but the term PCB is more commonly used. They are all circuit boards made by laminating one or more layers of copper foil onto a non-conductive plastic panel. Their main function is to provide support and connection for components with conductive tracks.

However, in some countries such as Japan, since PCB happens to be the name of a common poison, polychlorinated biphenyls, in order to avoid confusion, people prefer to use PWB to refer to this circuit board.

Looking back at the development of the electronics manufacturing industry, PWB has been used in the early days of the industry. At that time, the circuit connection method was relatively simple, mainly in the form of point-to-point connection. With the continuous advancement of technology, wires began to cross from one side of the board to the other, and even from one layer to another. The design of circuit boards is no longer limited to simple point-to-point connections, but has been given specific functions to meet the needs of increasingly complex electronic equipment.

In this process, PCB gradually emerged and eventually replaced the traditional point-to-point wiring board. In 1999, the IPC committee made a decision to clarify the unified use of the term PCB in the future, thus establishing the dominant position of PCB in industry specifications.

In the context of modern electronic manufacturing in most parts of the world, PWB can be regarded as the old name of PCB, while PCB has become a common and standard name for bare circuit boards without components. The unification of this term helps the global electronic manufacturing industry to standardize and normalize in terms of technical exchanges, production and manufacturing, and market circulation.

What is a PCB?

PCB, or printed circuit board, is an indispensable and important component in electronic equipment, used to achieve electrical connections between electronic components. It forms electrical connections between electronic components and supports and fixes components by laying conductive copper foil patterned on insulating materials.

What does pwb meaning?

PCB mainly consists of the following parts:

  • Substrate: Usually made of glass fiber or epoxy resin, providing mechanical support and insulation functions.
  • Conductive layer: Made of copper foil, responsible for transmitting current and signals.
  • Solder mask: Protects the copper foil of the circuit board from oxidation and prevents short circuits.
  • Character layer: Marks the position of components on the circuit board for easy assembly and maintenance.

According to the number of conductive layers, PCBs can be divided into the following categories:

  • Single-sided board: Only one side is a conductive layer, suitable for low-complexity circuits, such as simple home appliances or electronic toys.
  • Double-sided board: Both sides have conductive layers, suitable for more complex circuits, such as computers, automotive electronics, etc.
  • Multilayer board: There are four or more conductive layers, connected by internal wires, suitable for highly integrated circuits, such as communication equipment, high-end servers, etc.

What is the difference between PWB and PCB?

PWB (Printed Wiring Board), PCB (Printed Circuit Board), the difference between them is mainly reflected in the following aspects:

1. Origin of the name and emphasis on the meaning

  • PWB: In the early days, it mainly emphasized the printing of circuits, focusing on forming conductive circuits on the substrate through printing technology to achieve electrical connections between electronic components, and focusing more on the layout and construction of circuits.
  • PCB: It emphasizes the concept of circuits more, not only including conductive circuits, but also covering various electrical characteristics, signal transmission paths, and circuit function realization in circuit design. It is a more comprehensive term, involving the entire scope from circuit principles to actual physical layout.
What does pwb meaning?

2. Historical development context

  • PWB: It was widely used in the early stages of the development of the electronic manufacturing industry. At that time, electronic equipment was relatively simple, and the circuit was mainly a relatively simple point-to-point connection method. PWB could meet the basic line connection needs and provided a basic support platform for the assembly of early electronic products.
  • PCB: With the rapid development of electronic technology, the functions of electronic products have become more and more complex. PCB has gradually developed. It is not just a simple line connection, but also incorporates more circuit design concepts and technologies, thus gradually occupying a dominant position in the industry and largely replacing the early PWB.

3. Application scope and industry habits

  • PWB: Although it is no longer dominant in modern electronic manufacturing, the term PWB may still be used in some specific fields or traditional electronic equipment manufacturing, especially in some cost-sensitive, relatively simple circuit functions and low requirements for the application of new technologies. Some companies or engineers may continue to use the name PWB.
  • PCB: Currently widely used in the manufacture of various electronic equipment worldwide, PCB has become an indispensable basic component in the electronic manufacturing industry and a common standard term in the industry, which helps to improve the communication efficiency and standardization of the industry.

4. Technical standards and specifications

  • PWB: Due to its early application background and relatively simple technical characteristics, the relevant technical standards and specifications are relatively basic and simple, mainly focusing on basic circuit printing quality, line width and line spacing, and conduction performance. With the gradual reduction of PWB usage scenarios, the update and development of its technical standards are also relatively slow.
  • PCB: With the continuous advancement of technology and the continuous expansion of application fields, the technical standards and specifications of PCB have become extremely rich and strict. These standards and specifications are formulated and updated by international organizations (such as IPC – International Electronics Industry Connecting Association) and industry associations in various countries to ensure that the quality and performance of PCB can meet the needs of electronic products in different industries and different application scenarios.

Although there may be no essential difference between modern PWB and PCB in actual physical products, they have the above-mentioned differences and characteristics from multiple dimensions such as the origin of the term, historical development, scope of application, industry habits, and technical standards. In today’s electronic manufacturing industry, PCB is a more commonly used and widely recognized term, representing advanced electronic circuit manufacturing technology and complex circuit design concepts.

What are the common circuit board terms?

PB is the standardized name for bare board, which stands for printed board; PCBA is the abbreviation for printed circuit board assembly. When the PCB is assembled, it is called PCBA or PCB assembly. PCBA has been the term for all assembled circuit boards since the change in 1999. From users to technical committees, PCBA is also the preferred term for assembled boards.

PWA is the abbreviation for printed wiring assembly. It is an old term for PCB assembly or PCBA.

CCA is the abbreviation for circuit card assembly. CCA is the same as PCBA, but CCA is a less used term.

PCA is the abbreviation for printed circuit assembly. PCA is also the same as PCBA and is not common now.

From this we can conclude that PWB, PCB, circuit board are the same thing, referring to bare printed circuit boards; while PCA, CCA, PWA, PCBA are the same thing, referring to assembled circuit boards. Among them, PCB and PCBA are the two most widely used terms.

In short, although PWB, as a printed circuit board, has some subtle differences in terminology from PCB, in essence they are both indispensable basic components in electronic devices. They have witnessed the development of electronic technology together and will continue to play an important role in the future technological wave.

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What is heavy copper pcbs?
Friday, December 13th, 2024

What is heavy copper pcbs? That is, the copper foil thickness is greater than the conventional standard PCB. Generally speaking, when the copper foil thickness reaches 3 ounces per square foot (oz/ft²) and above, it can be called a heavy copper PCB.

The manufacturing process of heavy copper PCBs is more complicated than that of ordinary PCBs, requiring higher technical levels and professional equipment. Compared with ordinary PCBs, its characteristics are high current carrying, good heat dissipation, high mechanical strength and strong reliability. It is suitable for high-power electronic equipment, harsh working environments and fields with high reliability requirements.

What is heavy copper pcbs?

What is high copper thickness PCB?

High copper thickness PCB refers to a printed circuit board that uses thicker copper foil as the conductive material. In the standard PCB manufacturing process, the thickness of the copper foil is usually determined according to the application requirements, but when the thickness of the copper foil is greater than or equal to 3 ounces, this PCB is called a high copper thickness PCB.

Usually compatible with FR-4 dielectric, mainly used for inner layers rather than outer layers, plated through holes (PTH) usually need to be plugged/filled, and careful registration and lamination are required

Common heavy copper PCB thickness:

  • 2 oz (70 microns)
  • 3 oz (105 microns)
  • 4 oz (140 microns)
  • 6 oz (210 microns)
  • 8 oz (280 microns)
  • 10 oz (350 microns)

Application areas of heavy copper PCB:

  • Automotive electronics: widely used in key electronic devices such as automotive control modules, engine control systems, airbags, etc., because they can withstand high temperature, low temperature, corrosion and other environmental factors.
  • Power circuit: widely used in power modules, DC-DC converters and high power distribution boards, etc., capable of handling high current and high power requirements.
  • Industrial control system: used in high power motor drives, automation equipment and large mechanical control to meet the needs of high conductivity and mechanical strength.
  • Renewable energy systems: used in solar and wind energy systems to ensure stable system operation and reduce failure rates.

What are the advantages of heavy copper PCBs?

  • High conductivity: High copper PCB uses heavy copper foil as the conductive layer. Compared with ordinary PCB, its conductivity is significantly improved, which can carry larger current, reduce resistance loss and improve circuit efficiency.
  • High mechanical strength: Due to the increase in the thickness of copper foil, the mechanical strength of high copper PCB is also improved accordingly, which can withstand greater mechanical stress and impact, and is not easy to deform or damage.
What is heavy copper pcbs?
  • Good heat dissipation performance: High copper PCB can quickly transfer heat from the circuit to the surrounding environment, effectively prevent components from overheating and damage, and improve the reliability and service life of the equipment.

What type of copper is PCB?

There are mainly the following types of copper on PCB: red copper, copper clad plate and inner layer copper.

  • Red copper: Red copper is the earliest material used in circuit boards, and is widely used due to its good processing performance and conductivity. The main component of red copper is copper, and the other components are less, but the disadvantage is that it is easily oxidized and corroded.
  • Copper clad laminate: Copper clad laminate is a layer of copper foil on an inorganic substrate, usually used for double-sided and multi-layer circuit boards. The copper foil ensures the conductivity and connectivity of the circuit board, while the inorganic substrate provides mechanical strength and heat resistance.
  • Inner copper: Inner copper is used in multi-layer circuit boards, which are made of multiple layers of inorganic substrate and copper foil. It is usually used in high-density or high-speed design circuit boards, with better signal transmission performance and higher mechanical strength, but the manufacturing cost is higher.

In addition, there are different types of copper foil in PCB, including electrodeposited copper and rolled copper. Electrodeposited copper has a vertical grain structure and a rougher surface, which is suitable for rigid PCB boards; while rolled copper has a horizontal grain structure and a smoother surface, which is suitable for flexible and high-speed circuit boards.

How thick is 2 oz copper on PCB?

The thickness of 2 oz copper is about 70 microns. In PCB design, copper thickness is usually expressed in ounces (oz), and the thickness of 1 ounce of copper is about 35 microns, so the thickness of 2 ounces of copper is about 70 microns.

The copper thickness standard of PCB board is usually expressed in oz/ft² (ounces/square foot) or um (micrometer). The copper thickness of PCB board has an important impact on the performance and stability of the circuit board. The outer copper thickness mainly affects the stability of signal transmission and the ability to resist electromagnetic interference, while the inner copper thickness affects the signal transmission rate and signal-to-noise ratio.

Generally speaking, the thicker the outer copper thickness, the stronger the stability and signal strength of the circuit board, which is suitable for high-frequency and high-speed occasions; while the thinner the inner copper thickness, the more suitable for high-speed transmission signals, and the thicker the inner copper thickness, the more suitable for low-speed transmission signals and high signal-to-noise ratio signals.

Why use heavy copper PCB?

The main reasons for using heavy copper PCB include the following aspects:

  • Enhanced current carrying capacity: Heavy copper PCB uses a thicker copper layer, which can carry a larger current and reduce resistance and voltage drop. This is especially important for high-power applications or circuits that require high current transmission.
  • Optimize heat dissipation performance: Copper has good thermal conductivity, and a thicker copper layer can more effectively conduct heat away from hot spots and improve heat dissipation efficiency.
  • Improve signal transmission efficiency: Thicker copper layers can reduce losses and reflections during signal transmission and improve signal integrity.
  • Enhance mechanical strength: Thicker copper layers can increase the overall structural strength of PCBs, making them more resistant to physical shock and deformation.
  • Adapt to complex process requirements: Heavy copper PCBs can meet complex circuit design requirements through special process treatments, such as etching, drilling, gold plating, etc., to ensure the accuracy and reliability of circuit boards during manufacturing.

What is the most common copper thickness for PCB?

The most common PCB copper foil thickness is 35 microns. This thickness of copper foil is suitable for most consumer electronics products, can meet daily current and heat requirements, and has a relatively low cost and is suitable for large-scale production.

How are heavy copper PCBs made?

In the initial stage of making heavy copper PCBs, relatively heavy copper foil materials are selected. These copper foils are usually produced by electrolytic copper. During the electrolysis process, copper foils of different thicknesses can be produced by controlling the conditions of electrolysis, such as current density, electrolyte composition, and electrolysis time.

For situations where thicker copper foil is required, multiple lamination methods are used. Multiple layers of copper foil and insulating substrate materials are laminated according to design requirements, and then the copper foil and substrate are tightly combined through a high-temperature, high-pressure lamination process.

Next, the circuit pattern is manufactured on the outer layer of the heavy copper PCB, usually using a photolithography process. After that, according to the design requirements, holes are drilled on the heavy copper PCB to provide conditions for installing components and connecting circuits.

What is heavy copper pcbs?

After the drilling is completed, a metal layer is covered on the hole wall using electroplating technology to achieve a connection between the layers, and a layer of copper foil is electroplated on the hole wall to increase the thickness of the conductor and the surface pad. Next, the dry film and excess copper foil are removed, and chemical etchants are generally used to make the circuit pattern clearer.

Subsequently, the heavy copper PCB is subjected to surface treatment, such as gold plating, tin spraying, etc., to improve welding performance and corrosion resistance. Finally, the finished heavy copper PCB is strictly inspected and tested to ensure that its electrical and mechanical properties are consistent with the design requirements.

Professional Heavy copper PCB manufacturers – BEST Technology

The minimum width and thickness of the heavy copper PCB conductor are mainly determined based on the required current carrying capacity and the maximum temperature rise allowed for the conductor. From the perspective of its size specifications and actual manufacturing process, the routing of the circuit board may not be a regular rectangular shape.

What is heavy copper pcbs?

It is worth noting that the thicker copper conductor will significantly increase the overall thickness of the circuit board to a large extent. In terms of manufacturing process, the additive method (electroplating) process has certain advantages over the subtractive method (etching) process, but at the same time, its cost is relatively higher.

BEST Technology process capabilities:

  • Substrate: FR4/Aluminum
  • Copper thickness: 4OZ~10OZ
  • Extremely heavy copper thickness: 20~200 OZ
  • Contour: Milling, Punching, V-Cut
  • Solder mask: White oil/Black oil/Blue oil/Green oil/Red oil
  • Surface treatment: Immersion gold, tin spraying, OSP
  • Maximum panel size: 580*480mm(22.8″*18.9″)

Heavy copper PCB occupies an important position in the electronics field with its unique characteristics. With high current carrying capacity, good heat dissipation performance, higher mechanical strength and excellent reliability, it has become an ideal choice for many high-demand application scenarios. From power electronics to automotive electronics, from aerospace to medical equipment and communications, heavy copper PCB plays a key role.

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How to make two sided pcb in Altium?
Friday, December 13th, 2024

How to make two sided pcb Altium? Be familiar with the interface and basic operations of Altium Designer, accurately design the circuit schematic diagram, reasonably plan the PCB layout, make full use of the double-sided space, conduct fine wiring, ensure signal integrity, and correctly set the rules and parameters to meet production requirements.

How to make two sided pcb in Altium?

What is a double-sided PCB?

Double-Sided PCB refers to a printed circuit board with conductive copper layers on both sides, and the circuit between the two sides is connected through through holes (small holes). This design enables double-sided PCBs to implement more complex circuit layouts in limited space without significantly increasing the board size.

Double-sided PCBs are widely used in various application scenarios that require complex circuit layouts and high-density assembly, such as computers, communication equipment, industrial control, and consumer electronics.

Because it can achieve more complex circuit designs in a limited space, double-sided PCB is particularly suitable for applications that require higher-function electronic equipment, such as smart home equipment, computer hardware, medical equipment, etc.

How to make two sided pcb in Altium?

Here are the general steps for making a double-sided PCB in Altium:

  • Create a project: In Altium Designer, select “File” > “New” > “Project” to create a new PCB project.
  • Draw a schematic: Select “File†> “New†> “Schematic†to create a new schematic file. Add the required components to the schematic and connect them using wires.
  • Add package library: If you need to use a custom package library, you need to add it to the project. Select Design > Add/Remove Library and select the desired footprint library.
  • Generate PCB: After the schematic is drawn, select “Design” > “Update PCB Document” to import the components and connection information in the schematic into the PCB.
  • Layout components: In PCB, components are laid out according to design requirements. You can use Altium’s automatic layout tools or manual layout.
How to make two sided pcb in Altium?
  • Routing: Use Altium’s routing tools to route the connections between components. You can choose automatic routing or manual routing.
  • Add silkscreens and logos: Add silkscreens and logos to the PCB to easily identify components and connections.
  • Check and Validate: Use Altium’s Design Rule Checker tool to check that your PCB design meets requirements. Electrical rule checks, wiring rule checks, etc. can be performed.
  • Generate manufacturing files: After the PCB design is completed, select “File” > “Fabrication Outputs” to generate manufacturing files, such as Gerber files, drilling files, etc.

How to make two-sided PCB?

After designing the layout of the double-sided PCB in the PCB design software according to the circuit schematic diagram, the production process begins.

The complete process of making double-sided PCB:

  • Preparation materials: Choose a copper-clad laminate covered with copper foil of a specific thickness (such as 18μm, 35μm, etc.) on both sides, and determine the copper foil specifications according to circuit requirements.
  • Drilling: According to the drilling documents, use a CNC drilling machine to drill high-precision holes to ensure the connection paths for the circuits on each layer.
  • Copper immersion: Place the drilled PCB board in a copper immersion liquid to deposit a thin copper layer on the hole wall, laying the foundation for subsequent copper electroplating and ensuring the reliability of electrical connections.
  • Copper electroplating: Use the PCB board as the cathode to energize the copper ion plating solution, thicken the copper layer to the design standard, and enhance the electrical conductivity and mechanical properties.
  • Exposure and development: The Gerber file is made into a film. After applying photoresist to the copper-clad board, the film pattern is printed on the board through exposure equipment, and then the unexposed photoresist is dissolved with a developer to initially present the circuit pattern.
  • Etching: Use ferric chloride or acidic etching solution to dissolve the copper foil that is not protected by the photoresist, and form precise lines on both sides of the copper-clad board. Then use a film stripping solution to remove the remaining photoresist.
  • Make the solder mask layer: Use screen printing to apply solder mask ink of the selected color on the circuits on both sides of the board, and use screen printing to print white character ink on the corresponding positions of the cured solder mask layer to mark component information to facilitate assembly and debugging.
  • Drying treatment: Drying fixes the character ink to avoid fading and blurring.
  • Surface treatment: Dip tin or spray to coat the pad with tin layer to improve solderability, suitable for products with regular soldering requirements.

Can you put components on both sides of a PCB?

Components can be placed on both sides of the PCB. Both sides of the PCB double-sided panel can be wired and components placed, which can reduce the difficulty of wiring and is suitable for the design of complex circuits.

How to make two sided pcb in Altium?

In a double-board design, larger and denser components such as QFP and BGA are usually placed on the top layer of the board, while plug-in components can only be placed on the top layer. Smaller components and components are placed on the other side (bottom layer) of the plug-in components. Chip components with a small number of pins and loose arrangement.

How do you flip a PCB in Altium?

Use the shortcut key: Press the “V” key and then the “B” key to quickly flip the PCB view to the bottom layer. This method is like turning the PCB board over visually, making it easier to view the underlying component layout, wiring, etc.

Operation through the menu: Select the “View” menu, find the “Flip Board” option in the drop-down menu, and click it to flip the PCB view between the top and bottom layers. This method is relatively intuitive and suitable for users who are not familiar with shortcut keys.

How do you flip a component to the bottom in Altium?

Menu operation: Hold down the “Ctrl” key and use the left mouse button to click the components that need to be flipped one by one to select them all. Then follow the menu operation steps for flipping a single component, that is, select “Edit” – “Move” – ​​”Flip Selection”, so that multiple selected components can be flipped to the bottom together.

Shortcut key operation: First select multiple components, the selection method is the same as above, also hold down the “Ctrl” key and click the components. Then press the “L” key to flip these selected components to the bottom layer at the same time.

How do I mirror graphics in Altium?

In the schematic editing environment, select the component that needs to be mirrored. You can select it by left-clicking the component with the mouse. Then select the “Edit†menu and click on the “Mirror†option. Or use the shortcut key “Ctrl + M” to mirror the component in the horizontal direction. Properties such as the pin connections of the component will not change, only the graphic appearance will be mirrored.

How to make two sided pcb in Altium?

In the PCB editing environment, select the component to be mirrored by clicking it directly with the left mouse button. Select the “Move†submenu under the “Edit†menu and click on the “Mirror Selection†option. The component will be mirrored with the axis perpendicular to the PCB board plane as the axis of symmetry. This is useful when adjusting component layout, especially when you need to flip the component from top to bottom and mirror it at the same time, etc.

In addition, for some regularly shaped components (such as rectangular components), you can also select the component and hold down the “L” key to achieve the effect of flipping and mirroring the component between layers.

How do I rotate a whole PCB in Altium?

Use keyboard shortcuts to rotate in the PCB Editor:

Select the entire PCB (you can select the entire PCB through the “Edit” menu – “Select” – “All”). Press “Space” to rotate the PCB counterclockwise in 90° increments. This is a faster way to rotate, making it easier to adjust the direction of the PCB during the layout and routing process to better fit the workspace or meet specific layout ideas.

Rotate via menu options:

Also select the entire PCB first. Select the “Edit” menu – “Move” – ​​”Rotate Selection”. In the pop-up dialog box, you can set the rotation angle. The PCB can be rotated accurately according to the design requirements, such as inputting any angle such as 45°, 60°, etc., and then clicking the “OK” button to complete the rotation operation. This method is relatively more flexible and can meet the rotation needs of non-integer multiples of 90°.

During the design process, pay attention to key points, be familiar with the operation of the software, accurately design the circuit schematic, reasonably plan the PCB layout, conduct fine wiring, set correct rules and parameters, and conduct strict inspection and optimization. Only in this way can the quality and reliability of PCB design be ensured and meet the needs of practical applications.

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