Datasheet

PESD5ZX_SER_2 © NXP B.V. 2008. All rights reserved.
Product data sheet Rev. 02 — 4 April 2008 12 of 17
NXP Semiconductors
PESD5Zx series
Low capacitance unidirectional ESD protection diodes
7. Application information
The PESD5Zx series is designed for the protection of one unidirectional data or signal line
from the damage caused by ESD and surge pulses. The device may be used on lines
where the signal polarities are either positive or negative with respect to ground. The
PESD5Zx series provides a surge capability of 260 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 PESD5Zx as close to the input terminal or connector as possible.
2. The path length between the PESD5Zx 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 20. Application diagram
006aab071
ground
line to be protected
(positive signal polarity)
PESD5Zx
unidirectional protection of one line
ground
line to be protected
(negative signal polarity)
PESD5Zx