ESD Protection for PCB Design

Design of electronic products that need be followed ESD Release rules, because most of electronic products are 99% of the life cycle will be in an ESD environment, ESD interference will lead to be locked, and reset, loss of data or reliability problem. In ESD damage, static electricity can cause devastating damage to the I/O ports, is likely to cause damage to the product until the data bits ghosting, cause electronic equipment "hardware damage" of components. So engineers need to consider and grasp all the ESD problems in the design of the solution. 

Portable products would use low power logic chip, because of the metal oxide semiconductor (MOS) dielectric breakdown and the limitation of bipolar reverse junction current, the logic chips is sensitive to ESD. Control I/O port (USB ports, Ethernet port, etc.) of the chip are more important, because most of them are based on CMOS process to design and manufacture, which leads to the chip is sensitive to ESD damage. In addition, most of the I/O port (especially USB port) are hot plug system, all are highly susceptible to impact of ESD or air discharge.Thus, ESD protection in today's portable and USB application is very necessary
    
As far as possible use to multilayer PCB, ground and power supply, signal lines, the optimization design can reduce the common impedance and inductive coupling, it would be 1/10 to 1/100 of the double sided PCB.
    
As far as possible to let each signal layer close to a power or ground layer. For the top and the bottom are some components, many short lines and many high density PCBs, please consider to use the inner design.The majority of signal lines and power supply and ground are on the inner layers, and similar to the function of shielding Faraday box. 
    
For double layers PCB, tightly woven to power supply and ground grid. Usually principle is to testing - problem solving - to testing,  one cycle, each cycle would affect the at least one part of PCB design. In the process of PCB design, by predicting the majority of the design can be modified only components increase or decrease.