Anti-ESD PCB wiring design and layout

ESD-resistant PCB layout and wiring design are different from general PCB layouts. There are many techniques, and everyone understands them in daily design. Here I also summarize some anti-ESD PCB layout and wiring design techniques. hope that it can help us.　　Make sure that the signal wire is as short as possible. When the length of the signal wire is greater than 12 inches (30cm), a ground wire must be laid in parallel.　　Using a multi-layer PCB board structure, special power and ground planes are arranged on the inner layer of the PCB board. Use bypass and decoupling capacitors. Try to place each signal layer as close as possible to a power layer or ground layer. For high-density PCBs with components on the top and bottom surfaces, short connection lines and many filled grounds, internal wiring can also be used.　　 Where possible, fill the unused area with land, and connect the filled land of all layers at intervals of <2inch (5cm). The layout of components between each functional circuit and each functional circuit should be as compact as possible. Circuits or sensitive components that are susceptible to ESD should be placed near the center of the PCB board so that they do not affect each other. Other circuits can provide some shielding for them. In areas that can be directly hit by ESD, a ground wire must be placed near each signal line.　　 At the I/O interface of the device where ESD is easy to enter and the place where human hands often need to touch or operate, such as reset button, communication port, on/off button, function button, etc. Usually a transient protector, series resistor or magnetic beads are placed at the receiving end.　　 Ensure that the loop area between the signal line and the corresponding loop is as small as possible. For long signals, change the position of the signal line and the ground line every few centimeters or inches to reduce the loop area.　　Ensure that the loop area between the power supply and the ground is as small as possible, and place a high-frequency capacitor close to each power supply pin of the integrated circuit chip (IC).　　 When the length of the opening on the power supply or ground plane exceeds 8mm, use a narrow wire to connect both sides of the opening.　　 The reset line, interrupt signal line, or edge trigger signal line cannot be arranged close to the edge of the PCB board.　　Circular ground paths are arranged around the entire periphery of the PCB board, and the width of the circular ground of all layers should be greater than 100mil (2.54mm) as much as possible. Connect the ring grounds of all layers with via holes every 500 mils (12.7mm), and the signal line is more than 20 mils (0.5mm) away from the ring ground.