PROTECTION PRODUCTS - RailClamp
®
Description
RailClamps are surge rated diode arrays designed to
protect high speed data interfaces. The SRDA series
has been specifically designed to protect sensitive
components which are connected to data and trans-
mission lines from overvoltage caused by electrostatic
discharge
(ESD),
electrical fast transients
(EFT),
and
lightning.
The unique design incorporates surge rated, low
capacitance steering diodes and a TVS diode in a
single package. During transient conditions, the
steering diodes direct the transient current to ground
via the internal low voltage TVS. The TVS diode clamps
the transient voltage to a safe level. The low capaci-
tance array configuration allows the user to protect up
to four high-speed data lines. The SRDA05-4 may be
used to protect lines operating up to 5 volts while the
SRDA12-4 may be used on lines operating up to 12
volts.
These devices are in a 8-pin SOIC package. They are
available with a SnPb or RoHS/WEEE compliant matte
tin lead finish. The high surge capability (Ipp=25A,
tp=8/20μs) means it can be used in high threat
environments in applications such as CO/CPE equip-
ment, telecommunication lines, and video lines.
RailClamp
®
Low Capacitance TVS Diode Array
Features
Transient protection for high-speed data lines to
IEC 61000-4-2 (ESD) ±15kV (air), ±8kV (contact)
IEC 61000-4-4 (EFT) 40A (5/50ns)
IEC 61000-4-5 (Lightning) 24A (8/20μs)
Array of surge rated diodes with internal TVS diode
Protects four I/O lines
Low capacitance (<15pF) for high-speed interfaces
Low operating and clamping voltages
Solid-state technology
SRDA05-4 and SRDA12-4
Mechanical Characteristics
JEDEC SOIC-8 package
Lead Finish: SnPb or Matte Sn
Molding compound flammability rating: UL 94V-0
Marking : Part number, date code, logo
Packaging : Tape and Reel per EIA 481
Applications
USB Power and Data Line Protection
T1/E1 secondary IC Side Protection
T3/E3 secondary IC Side Protection
HDSL, SDSL secondary IC Side Protection
Video Line Protection
Microcontroller Input Protection
Base stations
I
2
C Bus Protection
Circuit Diagram
Schematic and PIN Configuration
REF1
I/O 1
1
8
REF 2
I/O 1
I/O 2
I/O 3
I/O 4
REF 1
2
7
I/O 4
REF 1
REF2
3
6
I/O 3
I/O 2
4
5
REF 2
S0-8 (Top View)
Revision 8/21/07
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