First, from the schematic to the PCB design process
Create component parameters -> Input Principle Netlist -> Design Parameter Settings -> Manual Layout -> Manual Routing -> Verify Design -> Review -> CAM Output.
Second, the parameter settings
Adjacent conductor spacing must meet electrical safety requirements, and spacing should be as wide as possible for ease of operation and production. The minimum spacing should be at least suitable for the voltage to withstand. When the wiring density is low, the spacing of the signal lines can be appropriately increased. The signal lines with high and low levels should be as short as possible and the spacing should be increased. Under normal circumstances Set the trace spacing to 8 mils. The distance from the edge of the pad to the edge of the board is greater than 1mm, which avoids pad defects during processing. When the traces connected to the pads are thinner, the connection between the pads and the traces is designed to be water droplets. This has the advantage that the pads are not easy to peel, but the traces are not easily disconnected from the pads.
Third, the component layout
Practice has proved that even if the schematic design of the circuit is correct and the PCB design is improper, it will adversely affect the reliability of the electronic device. For example, if the two thin parallel lines of the printed board are close together, the delay of the signal waveform will be formed, and the reflection noise will be formed at the end of the transmission line; the interference caused by the inconsistency of the power supply and the ground line will cause the product to be Performance is degraded, so when designing a printed circuit board, care should be taken to use the correct method.
Each switching power supply has four current loops:
(1). Power switch AC circuit
(2). Output rectifier AC circuit
(3). Input signal source current loop
(4). Output load current loop