How to pass ESD testing for motion controllers (MC)

To ensure the motion controller (MC) passes ESD testing, a multi-level protection system and optimized structural design are necessary. For all human-machine interfaces, communication ports, and I/O ports, equip each signal line with a TVS diode array, such as the ESDLC series, which offers fast response time and low clamping voltage. Connect small resistors or ferrite beads in series on the signal lines to limit peak ESD current. Use metal-cased connectors with low-impedance mating between their housings and the device chassis to provide a direct path to ground for ESD current. Maintain electrical continuity within the chassis, using conductive pads at gaps.

In PCB layout, protective devices must be placed close to connectors, and grounding traces should be short and wide. TVS protection can be added to the power supplies of internal sensitive chips. In software, implement watchdog timers or reset mechanisms for interfaces that may be locked due to ESD interference. During testing, perform contact discharge and air discharge tests according to IEC 61000-4-2 standards to verify its ability to withstand the corresponding levels and automatically recover.