
The USB configuration port of the data center switch must meet the IEC61000-4-2 Level 4 ±8kV contact discharge protection requirements while maintaining the integrity of a 480Mbps high-speed signal. The solution uses a four-channel ultra-low capacitance TVS array (Vrwm=5V, junction capacitance 0.8pF, clamping voltage 12V) of Eintraelectronics ESD0524P (Vrwm=5V, junction capacitance 0.8pF, clamping voltage 12V) connected in parallel to the D+/D- and VBUS four signals. This device is packaged in DFN2510 and protects four channels with a single device, saving PCB space. It is used in conjunction with an SMD2920-050-16V self-resetting fuse (holding current 0.5A, withstand voltage 16V) connected in series with VBUS to deal with overcurrent events. After actual testing, the eye diagram template margin is >20% after ESD ±8kV contact discharge and communication is uninterrupted. The PCB layout should have the TVS close to the USB connector pins and the differential traces with an equal length error of <5mil.