lxt9785 Intel Corporation, lxt9785 Datasheet - Page 116

• Manufacturer Part Number: lxt9785
• Description: Advanced 8-port 10/100 Mbps Phy Transceivers
• Manufacturer: Intel Corporation

LXT9785 and LXT9785E Advanced 8-Port 10/100 Mbps PHY Transceivers
4.2.1.1
118
Figure 7. Intel
Twisted-Pair Interface
The LXT9785/LXT9785E supports either 100BASE-TX or 10BASE-T connections over 100 :
CategoryUnshielded Twisted-Pair (UTP). Only a transformer, RJ-45, and bypass capacitors are
required to complete this interface. Using Intel's patented waveshaping technology, the transmitter
shapes the outgoing signal to help reduce the need for external EMI filters. Four slew rate settings
(refer to
page
transmit and receive terminations are built into the LXT9785/LXT9785E so no external
components are required between the LXT9785/LXT9785E and the external transformer. The
transmitter uses a transformer with a center tap to help reduce power consumption.
When operating at 100 Mbps, MLT3 symbols are continuously transmitted and received. When not
transmitting data, the LXT9785/LXT9785E generates “IDLE” symbols.
®
43) allow the designer to match the output waveform to the magnetic characteristics. Both
Management
LXT9785/LXT9785E Interfaces
Port LEDs/
Table 13, “Intel® LXT9785/LXT9785E Miscellaneous Signal Descriptions – PQFP” on
Interface
Interface
Controls
Addr &
MDIX/
MDIO
Contr
Data
Direct Drive
TXENn
TXDn_0
TXDn_1
TXCLK
RXCLK
RXDn_1
RXDn_0
RXERn
CRS_DVn
MDIOn
MDCn
MDINTn
MDDIS
LEDn_2
LEDn_2
LEDn_3
MDIX_Enb
Mode Select
ADD<4:0>
TPFIPn
TPFINn
TPFOPn
TPFONn
GNDD
VCCD
VCCIO
Revision Date: August 28, 2003
.01 uF
Document Number: 249241
+3.3 V
+2.5 V
+2.5 V
OR
Revision Number: 007
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Interface
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