Internal ESD protection circuits protect the transceivers against electrostatic discharges (ESD) according to IEC 61000-4-2 of up to ±15 kV contact and air discharge (for half-duplex devices) and up to ±8 kV contact and air discharge (for full-duplex devices). Bus structures also protect against electrical fast transients (EFT) according to IEC 61000-4-4 for up to ±4 kV. With careful system design, integrated bus structures can enable EFT Criterion A at the system level (minimum to no data loss when transient noise is present).