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
APPLICATION NOTES
• These Bel part types have been designed for use in 100 Mbps or 10/100 Mbps data transmission systems over
category 5 UTP/STP cable. Each Bel part type provides superior EMI noise suppression, high voltage isolation, wave
shaping and fast, but controlled rise times. All parts meet IEEE 802.3 standards, which includes 350µH OCL
(inductance) when 8mA DC bias is applied.
• These Bel part types have been tested and qualified for use with the Microlinear ML6692/6694/6698 chipsets in
adapter card, and multi-port repeater or switch applications. Bel also provides dual, 2-port and quad, 4-port designs
specifically for multi-port applications to provide cost and board space efficiency with no performance degradation.
Please refer to Bel data sheets 960019 and 960035.
• The S558-1287-03 has been specifically designed for 100 Mbps only applications.
• For 10/100 Mbps applications, Microlinear suggests the following table be used as a guideline:
Internal Internal
MAC Microlinear MII SYM 10 BT 10 BT Filters 7-Wire
DEC21140 6692, 2653 ✓✓ ✓
DEC21142 6692 ✓✓
DEC21143 6698 ✓✓ ✓
AM79C971 6692 ✓✓ ✓
I82557 6692, 2653 ✓✓*
MC91C100 6692, 2653 ✓✓
MX98713 6698 ✓✓ ✓ ✓
TNETE100 6692 ✓✓✓
*I82557 muxes the MII and the 7-wire signals.
• 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.
960007A
HIGH SPEED LAN MAGNETICS
