ESD Protection for High Speed Communication Ports
Electrostatic discharge (ESD) occurs when a charge is exchanged between two objects of unequal charge potential. ESD most often occurs between people and metal objects. It is a result of an electron build-up behaving as a capacitor when dielectric isolation is available.
Manmade materials, such as shoe soles, achieve dielectric isolation while someone walks on carpet creating kinetic energy. The potential threat of an ESD transient poses a challenge to system designers to incorporate overvoltage protection. Often, the included protection must have capacitance while not degrading the transmission rate.
Traditionally, the use of a high capacitor was used to provide protection. However, due to high speed requirements, the capacitance per line must be significantly reduced. It must be done while still providing overvoltage protection against potential threats. Threats can include ESD, electrical fast transients (EFT), or surges.
This whitepaper discusses standard requirements for ESD. It highlights overvoltage protection solutions for the most common high speed interfaces. These include USB, HDMI and Ethernet ports.