The optimum placement of the device
is as close to the connector as possible.
EMI during an ESD event
can couple from the trace being struck to other nearby unprotected
traces, resulting in early system failures.
The PCB designer must
minimize the possibility of EMI coupling by keeping any unprotected
traces away from the protected traces which are between the TVS and the
connector.
Route the protected traces as straight as possible.
Eliminate any sharp corners on the protected traces between the TVS and the
connector by using rounded corners with the largest radii possible.
Electric fields tend to build up on corners, increasing EMI
coupling.
If pin 3 is connected to ground, use
a thick and short trace for this return path.