When designing a multi-layer PCB, you need to pay attention to a basic situation, that is, how many wiring layers, ground planes, and power planes are needed to achieve the required functions of the circuit. The establishment of the number of wiring layers, ground planes, and power planes of the multi-layer PCB is related to the basic functions of the circuit, signal integrity, EMI, EMC, manufacturing costs, etc.
Unlike standard printed circuit boards, flexible PCB circuit boards use flexible polymers instead of typical FR4 materials. The commonly deployed flexible polymers require a polyimide film substrate or a polyester substrate, which is a strong material that does not soften under heating and remains flexible when thermoset. A large number of thermosetting resins such as PI remain rigid after heating, making them ideal for flexible circuit boards.
Whether the signal quality will be affected depends on the method of adding test points and how fast the signal is. Basically, the additional test points (without using the existing vias (via or DIP pins) as test points) may be added to the line or a short line may be pulled out from the line. The former is equivalent to adding a very small capacitor to the line, and the latter is an additional branch
With the rapid development of electronic technology and the widespread application of wireless communication technology in various fields, high frequency, high speed and high density have gradually become one of the significant development trends of modern electronic products. The high frequency and high speed digitalization of signal transmission force PCB to move towards micro-holes and buried/blind holes, fine wires, and uniform thin dielectric layers. High-frequency, high-speed, high-density multi-layer PCB design technology has become an important research field. This time, we mainly want to learn some practical skills in high-frequency PCB design.
With the development of electronic information technology, multi-layer PCBs are used in more and more fields. Traditionally, we define PCBs with more than four layers as “multi-layer PCBs” and PCBs with more than ten layers as “high-layer PCBs”. Whether or not a PCB manufacturer can produce high-layer PCBs is an important indicator of its strength. A PCB manufacturer that can produce high-layer PCBs with more than twenty layers is considered to be a PCB company with outstanding technical strength.
High-frequency choke: When wiring the high-frequency circuit board in the high-frequency PCB design, a high-frequency choke device must be connected when the digital ground, analog ground, etc. are connected to the common ground line. Generally, it is a high-frequency ferrite bead with a wire passing through the center hol
According to the rule of thumb, four-layer boards are usually used in high-density and high-frequency situations. Multi-layer PCBs are more than 20DB better than two-layer boards in terms of EMC. Under the condition of a four-layer board, a complete ground plane and a complete power plane can often be used. Under this condition, it is only necessary to connect the ground wires of the circuits divided into several groups to the ground plane, and the working noise is specially handled
With the continuous development of science and technology, the functional requirements of electronic devices are also constantly increasing. In order to meet this demand, HDI (High Density Interconnect) circuit boards came into being. HDI circuit boards have attracted much attention for their high density, high performance and high reliability, and have become an important bridge connecting future technologies.
With the development of high-frequency electronic technology, high-frequency PCB boards are increasingly widely used in various electronic systems. Recognizing the importance of high-frequency PCB boards, understanding their characteristics, and paying attention to their application areas are important directions for current scientific and technological innovation and research and development
This article mainly focuses on the concepts and design principles of microwave-grade high-frequency circuits/microwave circuits and high-frequency PCB design in a cutting-edge field of communication products