What are the categories of pcb?

What are the categories of pcb?

PCBs are diverse in materials, layers, and processes to suit different electronic products and their specific requirements, resulting in various classifications. Different materials and layer configurations of PCBs serve different functions. Today, we’ll discuss the specific categories of PCBs. Here’s the content:

Classification based on substrate properties:

  1. Rigid Boards: These boards are characterized by excellent heat resistance, mechanical strength, and dimensional stability. They are primarily used in high-speed, high-density circuits, and high-power circuits. Common rigid board materials include FR4, CEM-1, and CEM-3.
  2. Flexible Boards: In contrast to rigid boards, flexible boards offer better flexibility and are easier to process into small holes and fine traces. Therefore, they are mainly used in the manufacturing of Flexible Printed Circuits (FPCs). Common flexible board materials include Polyimide (PI) and Polyethylene Terephthalate (PET).
  3. Rigid-Flex Boards: These boards combine the characteristics of rigid metal foils and flexible polyimide substrates. They possess both the excellent properties of rigid boards and the flexibility of flexible boards. They find widespread application in circuit designs that require both rigidity and flexibility.

 

Classification based on substrate type:

       1.Paper-based Substrate: Made from paper impregnated with phenolic resin or epoxy resin and dried. These substrates have some mechanical strength and electrical properties but poor heat resistance and moisture resistance. They are mainly used in low-end electronic products.

      2.Glass Cloth-based Substrate: Made from glass cloth impregnated with epoxy resin or polyimide resin and dried. These substrates have higher mechanical strength, heat resistance, and electrical properties and are widely used in mid-to-high-end electronic products.

      3.Metal-based Substrate: Made from metal (such as aluminum, copper, etc.) with an insulating material and conductive layer on the surface. Metal substrates have good thermal conductivity and mechanical strength, mainly used in high-power circuits and applications with high reliability requirements.

 

Classification based on circuit layout layers:

      1.Single-sided pcb: A board with conductive patterns on only one side. These boards have a simple structure and low cost but limited wiring density and electrical performance. They are mainly used in simple electronic products.

      2.Double-sided pcb: A board with conductive patterns on both sides, connected through vias and pads. Double-sided boards have higher wiring density and electrical performance than single-sided boards and are widely used in various electronic products.

      3.Multilayer pcb: Made by stacking multiple layers of conductive and insulating layers, with electrical connections between layers achieved through blind vias, buried vias, etc. Multilayer boards have extremely high wiring density and electrical performance, suitable for complex high-density circuit designs.

Classification based on performance:

  1. High-Frequency PCB: High-frequency printed circuit boards are used for electronic components that require extremely fast signals. These types of boards are typically made from high-performance materials such as polytetrafluoroethylene (PTFE) and can provide signal speeds of up to 100 GHz. High-frequency PCBs exhibit excellent electrical performance and reliability in applications such as radio and microwave communication, radar systems, and medical devices.
  2. HDI PCB: PCBs designed to accommodate more components in smaller spaces. HDI boards consist of multiple layers of circuits interconnected through tiny microvias or holes with diameters smaller than 0.06 inches. The design of HDI PCBs varies depending on the application, including different types of vias, buried vias, and blind vias.
  3. High-Current PCB: High-current PCBs are designed to handle large currents. These boards are typically made from materials capable of withstanding high temperatures and have thicker traces to achieve better heat dissipation and lower inductance. They are used in applications such as power converters, motor drives, switch-mode power supplies, industrial control systems, LED lighting, and automotive electronics.
  4. High-Voltage PCB: High-voltage printed circuit boards can handle voltages in the range of 100V or higher, depending on the application. Similar to high-current types, these boards typically include thicker copper traces and larger components to aid in heat dissipation and reduce resistance.
  5. High-Tg PCB: High-Tg printed circuit boards have a higher rated temperature compared to standard PCBs. Tg refers to the temperature at which the material can maintain its original shape and mechanical properties. Therefore, high-Tg PCBs are typically made from special materials such as FR-4 with a higher glass transition temperature (Tg), often exceeding 170°C. These types of PCBs are used in advanced applications such as automotive, aerospace, and military electronics. Other applications include LED lighting and industrial control systems.

Share This Post