rclamp0514m Semtech Corporation, rclamp0514m Datasheet - Page 7

• Manufacturer Part Number: rclamp0514m
• Description: Railclamp Low-capacitance Tvs Diode Array
• Manufacturer: Semtech Corporation

that it is not uncommon for the V
exceed the damage threshold of the protected IC. This is
due to the relatively small junction area of typical dis-
crete components. It is also possible that the power
dissipation capability of the discrete diode will be ex-
ceeded, thus destroying the device.
The RailClamp is designed to overcome the inherent
disadvantages of using discrete signal diodes for ESD
suppression. The RailClamp’s integrated TVS diode
helps to mitigate the effects of parasitic inductance in
the power supply connection. During an ESD event, the
current will be directed through the integrated TVS diode
to ground. The maximum voltage seen by the protected
IC due to this path will be the clamping voltage of the
device.
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:
Matte Tin Lead Finish
Matte tin has become the industry standard lead-free
replacement for SnPb lead finishes. A matte tin finish
is composed of 100% tin solder with large grains.
Since the solder volume on the leads is small com-
pared to the solder paste volume that is placed on the
land pattern of the PCB, the reflow profile will be
determined by the requirements of the solder paste.
Therefore, these devices are compatible with both
lead-free and SnPb assembly techniques. In addition,
unlike other lead-free compositions, matte tin does not
have any added alloys that can cause degradation of
the solder joint.
PROTECTION PRODUCTS
Applications Information (continued)
2005 Semtech Corp.
Place the device near the input terminals or connec-
tors to restrict transient coupling.
Minimize the path length between the TVS and the
protected line.
Minimize all conductive loops including power and
ground loops.
The ESD transient return path to ground should be
kept as short as possible.
Never run critical signals near board edges.
Use ground planes whenever possible.
F
of discrete diodes to
7
RClamp0514M
PRELIMINARY
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