KSZ8873MLL_13 Datasheet, PDF (113/115 Pages) Micrel Semiconductor – Integrated 3-Port 10/100 Managed Switch with PHYs

Micrel, Inc.
KSZ8873MLL/FLL/RLL
Selection of Isolation Transformers
A 1:1 isolation transformer is required at the line interface. An isolation transformer with integrated common-mode choke
is recommended for exceeding FCC requirements.
Table 33 gives recommended transformer characteristics.
Table 33. Transformer Selection Criteria
Parameter
Turns Ratio
Open-Circuit Inductance (minimum)
Leakage Inductance (maximum)
Inter-Winding Capacitance (maximum)
D.C. Resistance (maximum)
Insertion Loss (maximum)
HIPOT (minimum)
Value
1 CT : 1 CT
350µH
0.4µH
12pF
0.9Ω
1.0dB
1500Vrms
Test Condition
100mV, 100kHz, 8mA
1MHz (minimum)
0MHz – 65MHz
Table 34. Qualified Single-Port Magnetics
Magnetic Manufacturer
Bel Fuse
Bel Fuse (MagJack)
Bel Fuse (MagJack)
Delta
LanKom
Pulse
Pulse (low cost)
Datatronic
Transpower
YCL
TDK (Mag Jack)
Selection of Reference Crystal
Table 35. Typical Reference Crystal Characteristics
Chacteristics
Frequency
Frequency Tolerance (maximum)
Load capacitance (maximum)
Series Resistance
Part Number
S558-5999-U7
SI-46001
SI-50170
LF8505
LF-H41S
H1102
H1260
NT79075
HB726
LF-H41S
TLA-6T718
Auto MDI-X
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Number of Port
1
1
1
1
1
1
1
1
1
1
1
Value
25.00000
±50
20
40
Units
MHz
ppm
pF
Ω
September 20, 2013
113
Revision 1.6