ELLXT971ABE.A4 Intel, ELLXT971ABE.A4 Datasheet - Page 27

• Manufacturer Part Number: ELLXT971ABE.A4
• Description: IC TRANS 3.3V ETHERNET 64-BGA
• Manufacturer: Intel
• Type: PHY Transceiverr

Specifications of ELLXT971ABE.A4

• Number Of Drivers/receivers: 1/1
• Protocol: IEEE 802
• Voltage - Supply: 3.14 V ~ 3.45 V
• Mounting Type: Surface Mount
• Package / Case: 64-BGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 870479

5.2.1.1
5.2.1.2
5.2.1.3
Datasheet
Document Number: 249414-003
Revision Date: June 18, 2004
Twisted-Pair Interface
The LXT971A 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 LXT971A
Transceiver continuously transmits and receives MLT3 symbols. When not transmitting data, the
LXT971A 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 LXT971A 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
Fiber Interface
The LXT971A Transceiver fiber port is designed to interface with common industry-standard fiber
modules. It incorporates an LVPECL interface that complies with the ANSI X3.166 standard for
seamless integration.
Fiber mode is selected through Register bit 16.0 by the following two methods:
Remote Fault Detection and Reporting
The LXT971A Transceiver supports two remote fault detection and reporting mechanisms.
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 LXT971A Transceiver receives a Remote Fault indication from its partner during auto-
negotiation, the following occurs:
1. Drive the SD input to a value greater than 600 mV during power-up and reset states (all
2. Configure Register bit 16.0 = 1 through the MDIO interface.
•
•
•
•
LVPECL signaling levels from a fiber transceiver are acceptable).
“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.
“Far-End Fault” is an optional PMA-layer function that may be embedded within PHY
devices.
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.
104.)
Intel
Table 62, “Transmit Control Register - Address 30, Hex 1E” on
®
LXT971A Single-Port 10/100 Mbps PHY Transceiver
27