How can a concentrator pass an ESD electrostatic discharge test?

The concentrator must pass the IEC 61000-4-2 ESD test (contact discharge ±8kV, air discharge ±15kV). The key design consideration is providing a low-impedance discharge path for all potential contact points. The metal casing must be properly grounded with a grounding impedance <0.1Ω. For buttons, indicator lights, etc., on non-metallic casings, their internal metal parts should be connected to the PCB ground via ESD protection devices (such as ESD5V0D3B). All external interfaces must have protective circuitry: power ports should use TVS diodes (such as SMCJ33CA) and varistors; communication ports should use ESD protection diodes (such as ESDSM712). In the PCB design, interface protection devices must be placed close to the connectors, with short and thick traces. ESD protection should also be added to the reset and debug ports of internal sensitive circuits (such as the MCU). The software should include a watchdog timer and abnormal reset handling. With comprehensive protection, the concentrator can successfully pass the ESD test.