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PSMF05

APPLIcATIoN INFoRMATIoN

FIGURE 1 - coMMoN-MoDE I/o PoRT PRoTEcTIoN (UNIDIREcTIoNAL)

Circuit connectivity is as follows:

• I/O 1 is connected to pin 1.

• I/O 2 is connected to pin 3.

• I/O 3 is connected to pin 4.

• I/O 4 is connected to pin 5.

• Pin 2 is connected to ground.

cIRcUIT BoARD REcoMMENDATIoNS

Circuit board layout is critical for electromagnetic compatibility protection. The following guidelines are recommended:

• The protection device should be placed near the input terminals or connectors, the device will divert the transient current

immediately before it can be coupled into the nearby traces.

• The path length between the TVS device and the protected line should be minimized.

• All conductive loops including power and ground loops should be minimized.

• The transient current return path to ground should be kept as short as possible to reduce parasitic inductance.

• Ground planes should be used whenever possible. For multilayer PCBs, use ground vias.

4

3

2

5

1

I/O 4

I/O 3

I/O 2

I/O 1