defining a degree of excellence
Bel Fuse Inc.
198 Van Vorst Street, Jersey City, NJ 07302 Tel: 201-432-0463 Fax: 201-432-9542 E-Mail: BelFuse@belfuse.com
Website: http://www.belfuse.com
Specifications subject to change without notice.
S553-5999-40
1CT:1CT
-16
-9
-0.5
-0.8
-1.1
-1.9
-35
-35
-20
-55
-50
-45
MECHANICAL
SCHEMATIC
960043A
Designed for use with token ring transceivers developed
by Texas Instruments and Madge
Complete single port device, including transmit and
receive channels in one package
Integrated transformers and common mode chokes
Compliant with IEEE 802.5 standards
Robust surface mount packaging rated to meet 225C
peak IR reflow temperature
For use in either 100 ohm UTP or 150 ohm STP media
systems
TOKEN RING NETWORKING
COMPONENTS
ELECTRICALS AT 25C (each channel)
Return Loss
Insertion Loss
Common to Common
Crosstalk
Turns
(dB) Min
(dB) Max
Mode Rej (dB) Min
(dB) Min
Part No.
Ratio
1-17MHz 17-25MHz
4MHz 8MHz 16MHz 24MHz
5MHz 20MHz 200MHz
8MHz 16MHz 24MHz
defining a degree of excellence
Corporate Office
Bel Fuse Inc.
198 Van Vorst Street, Jersey City, NJ 07302-4496
Tel: 201-432-0463
Fax: 201-432-9542
E-Mail: BelFuse@belfuse.com
Internet: http://www.belfuse.com
Far East Office
Bel Fuse Ltd.
8F/8 Luk Hop Street
San Po Kong
Kowloon, Hong Kong
Tel: 852-2328-5515
Fax: 852-2352-3706
European Office
Bel Fuse Europe Ltd.
Preston Technology Management Centre
Marsh Lane, Preston PR1 8UD
Lancashire, U.K.
Tel: 44-1772-556601
Fax: 44-1772-888366
960043A
APPLICATION NOTES
APPLICATION CIRCUIT
TOKEN RING NETWORKING
COMPONENTS
Bel has created this product for use with token ring 4/16 Mbps transceivers developed by Texas Instruments and
Madge. The impedance of this part has been optimized for use in either 100 ohm UTP or 150 ohm STP media
applications with only one RJ-45 connection. The Bel module provides isolation and impedance matching transformers
plus common mode choke for both transmit and receive channels. External filtering is required.
Suppression of board induced noise can be achieved with precision layout instructions, along with careful consideration
of the selection and placement of discrete components for the interface circuit.
Bel's low profile, surface mount packaging is ideal for high speed pick and place machinery. Parts can be shipped on
tape and reel for high speed placement. Construction processes have been implemented for thermal compatibility
with high temperature IR reflow assembly processing. Post dipping of leads assist with PC board solderability. Each
part is optically inspected to meet rigid coplanarity requirements.
OCL (inductance) of each transformer is 616 H minimum. Optional lower inductance models can be made available.
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