February 19, 2019
In high-speed designs, the characteristic impedance of the controllable impedance plates and lines is one of the most important and common problems. First, let's look at the definition of a transmission line: a transmission line consists of two conductors of a certain length, one for transmitting signals and the other for receiving signals (remember that the "loop" replaces the concept of "ground"). In a multi-layer board, each line is part of the transmission line and the adjacent reference plane can be used as a second line or loop. The key to a line becoming a "perfect" transmission line is to keep its characteristic impedance constant throughout the line.
February 19, 2019
The design performance of multi-layer boards is mostly similar to single-panel or double-panel, which is to avoid avoiding too many circuits to fill too small space, resulting in impractical tolerances, high inner layer capacity, and possibly even dangerous products. Quality safety. Therefore, the performance specification should consider the complete evaluation of the thermal shock, insulation resistance, welding resistance, etc. of the inner layer. The following sections describe important factors that should be considered in the design of multilayer boards.
February 19, 2019
One of the main purposes of the design of the circuit schematic is to provide a network table for the design of the PCB board and to prepare the basis for the design of the pcb board.
February 15, 2019
55 elements
February 15, 2019
The substrate of the circuit board itself is made of a material that is insulated and not easily bent. The small circuit material that can be seen on the surface layer is copper foil. The original copper foil is covered on the entire circuit board, and is partially etched away during the production process, leaving a small line of mesh. These lines are called wires or wires and are used to provide electrical connections to the components on the board. Usually the color of the PCB board is brown or green, which is the color of the solder resist paint. It is an insulating protective layer that protects the copper wire and prevents the part from being soldered to the wrong place.