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It is noted that TVS should be placed close to the connector. What is the significance of placing close the connector?

Added the snapshot for reference

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To prevent induced or conducted (due to breakdown) spikes on other traces.

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The App Note explains it already.

"However, I ESD can still be "steered " towards the TVS by making L4 much larger than L1. This is accomplished by placing the TVS as near to the ESD Source as the PCB design rules allow while placing the Protected IC far away from the TVS."

Re-read it carefully until understood.

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Actually, it is not always the best solution to put it as close as possible to the source. The best solution depends on the shielding of the product.

If the return path has a low impedance path to a large conducting surface, the statement is correct. The esd will flow directly to the conductor with a relatively large capacitance to ground. It will transfer the energy away from the circuit more easily.

If the product has no direct path to loose the energy, it is good to limit the current by adding inductance and/or resistance between the source and the TVS (thin trace or ferrite). It will limit di/dt, avoids breakdown of TVS, limits emmission, etc. The negative part is that the peak voltage at the point of impact is higher (dv/dt aswell), but your circuit connected to the TVS is protected.

Stick to the other hint in the list!

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