There are many forms of matter, such as solid, liquid, gas, plasma and so on. We usually call materials with poor conductivity, such as coal, artificial crystal, amber, ceramics and so on, insulators. Metals with good conductivity, such as gold, silver, copper, iron, tin and aluminum, are called conductors. The material between conductor and insulator can be simply called semiconductor. Compared with conductors and insulators, the discovery of semiconductor materials is the latest. Until the 1930s, when the purification technology of materials was improved, the existence of semiconductors was really recognized by the academic community.
When designing a four-layer PCB circuit board, how is the stack-up generally designed?
In the production of electronic products, there will be a production process of printed circuit board. Printed circuit boards are used in electronic products in all industries. It is the carrier of electronic schematic diagram that can realize the design function and turn the design into physical products
Printed circuit board (PCB) is a substrate for assembling electronic parts. It is a printed board that forms the connection between points and printed components on the general substrate according to the predetermined design. According to different classification methods
According to the number of layers, there are three types of single-sided, double-sided, and multi-layer circuit boards, which are distinguished according to the circuit layers inside.
Our common computer boards and cards are basically epoxy resin glass cloth based double-sided printed circuit boards. One side is the plug-in components, and the other side is the welding surface of the component feet. It can be seen that the welding points are very regular
