Bel Fuse Inc. 198 Van Vorst Street, Jersey City, NJ 07302 Tel 201-432-0463 Fax 201-432-9542 www.belfuse.com
MODEM MAGNETICS
2000 Bel Fuse Inc. Specifications subject to change without notice. 05.00
TM00403
T4-7
Global V.90 and V.34 Transformers
ELECTRICAL SPECIFICATIONS at 25 C
Intended for use in high-speed modem applications
Features very low interwinding capacitance, well-
isolated windings, and low total harmonic distortion
Qualified per Bellcore TR-TSY-000357-1
Designed to comply with EN60950 requirements for a
reinforced insulation barrier with a working voltage
of 250V
Approved by UL, CSA and BABT
Minimum interwinding breakdown voltage of 3000 Vrms
1
3
6
4
Primary
Secondary
SCHEMATIC
2778A
2778B
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CORPORATE
Bel Fuse Inc.
198 Van Vorst Street
Jersey City, NJ 07302
Tel
201-432-0463
Fax
201-432-9542
www.belfuse.com
FAR EAST
Bel Fuse Ltd.
8F / 8 Luk Hop Street
San Po Kong
Kowloon, Hong Kong
Tel
852-2328-5515
Fax 852-2352-3706
www.belfuse.com
EUROPE
Bel Fuse Europe Ltd.
Preston Technology Management Centre
Marsh Lane, Suite G7, Preston
Lancashire, PR1 8UD, U.K.
Tel
44-1772-556601
Fax 44-1772-888366
www.belfuse.com
MODEM MAGNETICS
2000 Bel Fuse Inc. Specifications subject to change without notice. 05.00
TM00403
T4-8
Global V.90 and V.34 Transformers
MECHANICAL
0.565
[14.35]
max
0.118 [3.00]
0.020 [0.508]
sq. wire
3
4
6
1
0.300
[7.62]
0.710 [18.03]
max sq.
0.50 [12.7]
Note: Unless otherwise specified, dimensions
are nominal and in inches [millimeters].
2778A
2778B
2778B
58
17 mH
58
6
4
10 pF
10 H
10 pF
3
1
25 k
2778A
TYPICAL SPICE TRANSMISSION MODEL
45 k
18 mH
typ
58
typ
10 pF
15
H
58
typ
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