PROTECTION PRODUCTS

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PROTECTION PRODUCTS

STF701

T-Filter with TVS Diode Array

For EMI Filtering and ESD Protection

Description

Features

Circuit Diagram

Schematic & PIN Configuration

Revision 9/2000

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

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.

Applications

Mechanical Characteristics

protection

SC70-5L (Top View)