5
© 2010 Semtech Corp.
www.semtech.com
PROTECTION PRODUCTS
RClamp0504PA
Device Connection Options for Protection of Four
High-Speed Data Lines
This device is designed to protect data lines by
clamping them to a fixed reference. When the voltage
on the protected line exceeds the reference voltage
the steering diodes are forward biased, conducting the
transient current away from the sensitive circuitry.
Data lines are connected at pins 1, 3, 4 and 6. The
center pin should be connected directly to a ground
plane. The path length is kept as short as possible to
minimize parasitic inductance. Pin 2 is not connected.
The positive reference is connected at pin 5. The
options for connecting the positive reference are as
follows:
1. To protect data lines and the power line, connect
pin 5 directly to the positive supply rail (V
CC
). In this
configuration the data lines are referenced to the
supply voltage. The internal TVS diode prevents
over-voltage on the supply rail.
2. In applications where the supply rail does not exit
the system, the internal TVS may be used as the
reference. In this case, pin 5 is not connected.
The steering diodes will begin to conduct when the
voltage on the protected line exceeds the working
voltage of the TVS (plus one diode drop).
Protection of Four Data Lines and Power Supply Line
Applications Information
Protection of Four Data Lines Using Internal TVS
Diode as Reference
1
Gnd
1
Gnd
Figure 1Figure 1
Figure 1Figure 1
Figure 1
. Pin Conf. Pin Conf
. Pin Conf. Pin Conf
. Pin Conf
iguration (Tiguration (T
iguration (Tiguration (T
iguration (T
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1
Gnd
2
3
6
5
4
