lxt971a Intel Corporation, lxt971a Datasheet - Page 49

• Manufacturer Part Number: lxt971a
• Description: 3.3v Dual-speed Fast Ethernet Phy Transceiver
• Manufacturer: Intel Corporation

Datasheet
Document #: 249414
Revision #: 002
Rev. Date: August 7, 2002
Figure 22. Typical Twisted-Pair Interface - Switch
1. Center-tap current may be supplied from 3.3 V VCCA as shown. Additional power savings
2. The 100 : transmit load termination resistor typically required is integrated in the
3. Magnetics without a receive pair center-tap do not require a 2 kV termination.
4. RJ-45 connections shown are for a standard switch application. For a standard NIC RJ-45
may be realized by supplying the center-tap from a 2.5 V current source. A separate ferrite
bead (rated at 50 mA) should be used to supply center-tap current.
LXT971A.
setup, see
LXT971A
Figure 23 on page
TPFON
TPFOP
TPFIN
TPFIP
VCCA
SD/TP
GND
0.1PF
270 pF 5%
270 pF 5%
0.1PF
2
50:
50:
0.01 PF
50.
LXT971A 3.3V Dual-Speed Fast Ethernet Transceiver
.01PF
1
1:1
1:1
3
*
*
50 :
50 :
* = 0.001 PF / 2.0 kV
50 :
50 :
50 :
50 :
RJ-45
4
1
2
3
4
5
6
7
8
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