SR70 Datasheet, PDF (1/6 Pages) Protek Devices – STEERING DIODE ARRAY

PROTECTION PRODUCTS
Description
RailClamps are surge rated diode arrays designed to
protect high speed data interfaces. The SR70 has
been specifically designed to protect sensitive compo-
nents which are connected to data and transmission
lines from over-voltages caused by ESD (electrostatic
discharge), EFT (electrical fast transients), and light-
ning. The SR70 has been optimized for use on ADSL
and other high-speed interfaces.
The unique design of the SR70 integrates four surge
rated, low capacitance steering diodes in a low profile
SOT-143 package. It has a typical capacitance of only
5pF and may be used to protect two high-speed lines
without sacrificing signal integrity. The SR70 is de-
signed to replace “standard” rectifiers that are not
rated for the high energy surges that are normally
expected in telecommunications applications.
During transient conditions, the steering diodes direct
the transient to either the positive side of the power
supply line or to ground. The maximum clamping
voltage seen by the protected circuit will be one diode
drop (V_F) above the supply (reference) voltage. The
SR70 may be used as a stand alone device or in
conjunction with TVS diodes for enhanced protection.
SR70
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) 1kV, 24A (8/20µs)
‹ Array of surge rated, low capacitance diodes
‹ Protects two I/O lines
‹ Low capacitance (5pF typical) for high-speed
interfaces
‹ Low clamping voltage
‹ Solid-state silicon-avalanche technology
Mechanical Characteristics
‹ JEDEC SOT-143 package
‹ UL 497B listed
‹ Molding compound flammability rating: UL 94V-0
‹ Marking : R70
‹ Packaging : Tape and Reel per EIA 481
Applications
‹ ADSL Lines
‹ I²C Bus Protection
‹ Video Line Protection
‹ T1/E1 secondary IC Side Protection
‹ Portable Electronics
‹ Microcontroller Input Protection
‹ WAN/LAN Equipment
‹ ISDN S/T Interface
Circuit Diagram
Schematic & PIN Configuration
Pin 2
Pin 4
Pin 3
Pin 1
Revision 04/18/03
1
4
1
2
3
SOT-143 (Top View)
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