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SMS05
thru
SMS24C
APPLICATION NOTE
CIRCUIT BOARD LAYOUT RECOMMENDATIONS
Circuit board layout is critical for Electromagnetic
Compatibility (EMC) 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.
The SMS Series are TVS arrays designed to protect I/O or data lines from the damaging effects of ESD or EFT. This product series provides both
unidirectional and bidirectional protection, with a surge capability of 350 Watts PPP per line for an 8/20µs waveform and ESD protection > 25 kilovolts.
UNIDIRECTIONAL COMMON-MODE CONFIGURATION (Figure 1)
The SMS Series provides up to four (4) lines of protection in a common-mode configura-
tion as depicted in Figure 1.
Circuit connectivity is as follows:
✔Line 1 is connected to Pin 1.
✔Line 2 is connected to Pin 3.
✔Line 3 is connected to Pin 4.
✔Line 4 is connected to Pin 6.
✔Pin 5 is connected to ground.
✔Pin 2 is not connected.
BIDIRECTIONAL COMMON-MODE CONFIGURATION (Figure 2)
The SMSxxC Series provides up to four (4) lines of protection in a common-mode
configuration as depicted in Figure 2.
Circuit connectivity is as follows:
✔Line 1 is connected to Pin 1.
✔Line 2 is connected to Pin 3.
✔Line 3 is connected to Pin 4.
✔Line 4 is connected to Pin 5.
✔Pin 6 is connected to ground.
✔Pin 2 is not connected.
Figure 1 - Unidirectional Configuration
Common-Mode I/O Port Protection
LINE 1
LINE 2
LINE 3
LINE 4
I/O PORT
Figure 2 - Bidirectional Configuration
Common-Mode I/O Port Protection
LINE 1
LINE 2
LINE 3
LINE 4
I/O PORT