PESDXS4UD_SER_2

© NXP B.V. 2009. All rights reserved.

Product data sheet

Rev. 02 — 21 August 2009

8 of 12

NXP Semiconductors

PESDxS4UD series

Quadruple ESD protection diode arrays in a SOT457 package

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Application information

The PESDxS4UD series is designed for protection of up to 4 unidirectional data lines from

the damage caused by ESD and surge pulses. The PESDxS4UD series may be used on

lines where the signal polarities are above or below ground. The PESDxS4UD series

provides a surge capability of 200 W per line for an 8/20

µs waveform.

Circuit board layout and protection device placement

Circuit board layout is critical for the suppression of ESD, Electrical Fast Transient (EFT)

and surge transients. The following guidelines are recommended:

1. Place the PESDxS4UD as close to the input terminal or connector as possible.

2. The path length between the PESDxS4UD and the protected line should be

minimized.

3. Keep parallel signal paths to a minimum.

4. Avoid running protected conductors in parallel with unprotected conductors.

5. Minimize all Printed-Circuit Board (PCB) conductive loops including power and

ground loops.

6. Minimize the length of the transient return path to ground.

7. Avoid using shared transient return paths to a common ground point.

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

vias.

Fig 10. Application diagram

006aaa762

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2

3

6

data- or transmission lines

unidirectional protection of 4 lines

bidirectional protection of 3 lines

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4

1

2

3

n.c.

6

5

n.c.

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