T-Filter with TVS Diode Array
For EMI Filtering and ESD Protection
PROTECTION PRODUCTS
Description
The STF701 is a low pass T-filter with integrated TVS
diodes. It is designed to provide bi-directional un-
wanted EMI/RFI signals filtering and electrostatic
discharge (ESD) protection in portable electronic
equipment. Each device will provide filtering and
protection for two I/O lines.
The STF701 is constructed using thin-film-on-silicon
technology. The device has very low insertion loss in
the pass band (to approximately 10MHz) and good
attenuation at high frequencies (approximately
100MHz to 1GHz). Each line features two stages of
TVS diode protection. The TVS diodes provide effec-
tive suppression of ESD voltages in excess of 15kV (air
discharge) and 8kV (contact discharge) per IEC 61000-
4-2, level 4.
The clamping characteristics of the device are opti-
mized by the use of two TVS diodes. The TVS diodes
serve a dual purpose of protecting the internal capaci-
tor and the sensitive IC connected to the line. The
voltage divider action of the circuit means the voltage
across the protected IC will be very close to the break-
down voltage (V
BR
) of the second TVS.
The small size and integrated feature of the STF701
minimizes required board space and increases system
reliability. The STF701 is suitable for use in portable
communications devices such as cellular handsets and
accessory kits.
STF701
Features
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Bidirectional EMI/RFI filtering with integrated ESD
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protection
ESD protection to
IEC 61000-4-2 Level 4
Filtering and ESD protection for two data lines
Low insertion loss to 10MHz
Good attenuation of high frequency signals
Low TVS operating voltage (5V)
Low clamping voltage
Low leakage current
Thin-film-on-silicon technology
Mechanical Characteristics
EIAJ SC70-5L package
Molding compound flammability rating: UL 94V-0
Marking : 701
Packaging : Tape and Reel per EIA 481
Applications
Cell phone handsets
Cell phone accessories
RF Communications equipment
Laptop Computers
Two-way pagers
GPS Devices
Circuit Diagram
Schematic & PIN Configuration
SC70-5L (Top View)
Revision 9/2000
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