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PROTECTION PRODUCTS
PROTECTION PRODUCTS
SLVE2.8 and SLVG2.8
Circuit Diagrams
Common Mode Protection (SLVE2.8 and SLVG2.8)
Device Connection
Electronic equipment is susceptible to transient distur-
bances from a variety of sources including: ESD to an
open connector or interface, direct or nearby lightning
strikes to cables and wires, and charged cables “hot
plugged” into I/O ports. The SLV series is designed to
protect sensitive components from damage and latch-
up which may result from such transient events. The
SLVG2.8 is designed to protect one unidirectional line
while the SLVE2.8 is designed to protect one bidirec-
tional line (or two differential lines). The options for
connecting the devices are as follows:
z SLVE2.8: Common mode protection of one bidirec-
tional data line is achieved by connecting the data
line input/output at pins 2 and 3. Pins 1 and 4 are
connected to ground. For differential protection,
pins 1 and 4 can be connected to a second I/O
line. For best results, the ground connection
should be made directly to a ground plane on the
board. The path length should be kept as short as
possible to minimize parasitic inductance.
z SLVG2.8: Common mode protection of one unidi-
rectional line is achieved by connecting the line to
be protected at pins 2 and 3. Pins 1 and 4 are
connected to ground. For best results, the ground
connection should be made directly to a ground
plane on the board. The path length should be
kept as short as possible to minimize parasitic
inductance.
Circuit Board Layout Recommendations for Suppres-
sion of ESD.
Good circuit board layout is critical for the suppression
of ESD induced transients. The following guidelines are
recommended:
z Place the TVS near the input terminals or connec-
tors to restrict transient coupling.
z Minimize the path length between the TVS and the
protected line.
z Minimize all conductive loops including power and
ground loops.
z The ESD transient return path to ground should be
kept as short as possible.
z Never run critical signals near board edges.
z Use ground planes whenever possible.
1
2
3
4
Line
In
Line
Out
1
2
3
4
Line 2
In
Line 2
Out
Line 1
In
Line 1
Out
Differential Mode Protection (SLVE2.8 only)
1
2
3
4
1
2
3
4
SLVG2.8 SLVE2.8
Applications Information
