SMDA03LC
thru
SMDA24LCC
405074.R8 3/08 www.protekdevices.com
The SMDAxxLC & SMDAxxLCC Series are TVS arrays designed to protect I/O or data lines from the damaging effects of ESD, EFT and other types of
surges. This product series provides both unidirectional and bidirectional protection, with a surge capability of 500 Watts PPP per line for an 8/20µs
waveform and ESD protection > 40kV.
UNIDIRECTIONAL COMMON-MODE CONFIGURATION(Figure 1)
The SMDAxxLC Series provides up to four (4) lines of protection in a common-mode
configuration as depicted in Figure 1.
Circuit connectivity is as follows:
✔Line 1 is connected to Pin 5.
✔Line 2 is connected to Pin 6.
✔Line 3 is connected to Pin 7.
✔Line 4 is connected to Pin 8.
✔Pins 1-4 are connected to ground.
BIDIRECTIONAL COMMON-MODE CONFIGURATION (Figure 2)
Ideal for Ethernet applications, SMDAxxLCC Series provides up to four (4) lines of
protection in a common-mode configuration as depicted in Figure 2.
Circuit connectivity is as follows:
✔TPIN is connected to Pin 5.
✔TPIP is connected to Pin 6.
✔TPON is connected to Pin 1.
✔TPOP is connected to Pin 2.
✔Pins 3, 4, 7 & 8 are connected to ground.
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.
Figure 1. Unidirectional Common-Mode Protection
5
6
7
8
1234
LINE 4
LINE 3
LINE 2
LINE 1
GND PLANE
Figure 2. Bidirectional Common-Mode Protection
5
6
7
8
1234
TPIN
TPIP
TPOP
TPON
ETHERNET REPEATER
APPLICATION NOTE