ESD protection diodes

Since the transmitting coil is a easy entry point for ESD (relatively large area with remarkable capacitive

coupling),a good application design should consider protections for the most exposed pins: AC1 and AC2.

Uni-directional Transient Voltage Suppression (TVS) diodes at both pins are recommended.

ESDs have essentially a common mode nature and, although the receiving coil has low DC-resistance, its AC

impedance may appear quite high to fast voltage spikes: independent clamping at AC1 and AC2 pins is thus

mandatory.

The knee-voltage of the TVS diodes should be selected considering the maximum VINV voltage plus some

margin to avoid non-negligible leakage current at higher temperature, while their energy dissipation capability

should be maximized considering the size of the package.

STWBC86

External components selection

DS14079 - Rev 1

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