WJLXT972MLC.A4 S L7U9 Intel, WJLXT972MLC.A4 S L7U9 Datasheet - Page 24

• Manufacturer Part Number: WJLXT972MLC.A4 S L7U9
• Manufacturer: Intel

Specifications of WJLXT972MLC.A4 S L7U9

• Lead Free Status / RoHS Status: Compliant

Intel
5.2.1.1
5.2.1.2
24
®
LXT972M Single-Port 10/100 Mbps PHY Transceiver
Note:
Twisted-Pair Interface
The LXT972M Transceiver supports either 100BASE-TX or 10BASE-T connections over 100 Ω,
Category 5, Unshielded Twisted Pair (UTP) cable. When operating at 100 Mbps, the LXT972M
Transceiver continuously transmits and receives MLT3 symbols. When not transmitting data, the
LXT972M Transceiver generates “IDLE” symbols.
During 10 Mbps operation, Manchester-encoded data is exchanged. When no data is being
exchanged, the line is left in an idle state. Link pulses are transmitted periodically to keep the link
up.
Only a transformer, RJ-45 connector, load resistor, and bypass capacitors are required to complete
this interface. On the transmit side, the LXT972M Transceiver has an active internal termination
and does not require external termination resistors. Intel's patented waveshaping technology shapes
the outgoing signal to help reduce the need for external EMI filters. Four slew rate settings allow
the designer to match the output waveform to the magnetic characteristics. On the receive side, the
internal impedance is high enough that it has no practical effect on the external termination circuit.
(For the slew rate settings, see
page
On the LXT972M Transceiver, MDIX crossover (MDIX) is supported by board design.
Remote Fault Detection and Reporting
The LXT972M Transceiver supports the remote fault detection and reporting mechanisms.
“Remote Fault” refers to a MAC-to-MAC communication function that is transparent to PHY layer
devices. It is used only during auto-negotiation, and is applicable only to twisted-pair links.
Remote Fault Detection. Register bit 4.13 in the Auto-Negotiation Advertisement Register is
reserved for Remote Fault indications. It is typically used when re-starting the auto-negotiation
sequence to indicate to the link partner that the link is down because the advertising device
detected a local fault.
When the LXT972M Transceiver receives a Remote Fault indication from its partner during auto-
negotiation, the following occurs:
•
•
Register bit 5.13 in the Link Partner Base Page Ability Register is set.
Remote Fault Register bit 1.4 in the MII Status Register is set to pass this information to the
local controller.
89.)
Table 56, “Transmit Control Register - Address 30, Hex 1E” on
Document Number: 302875-005
Revision Date: 27-Oct-2005
Datasheet