WG82574L S LBA9 Intel, WG82574L S LBA9 Datasheet - Page 483

• Manufacturer Part Number: WG82574L S LBA9
• Description: CONTROLLER, ENET, INTEL 82574L, 64PQFN
• Manufacturer: Intel

Specifications of WG82574L S LBA9

• Ethernet Type: IEEE 802.3, IEEE 802.3u, IEEE 802.3ab
• Supply Voltage Range: 3V To 3.6V
• Operating Temperature Range: 0°C To +85°C
• Digital Ic Case Style: QFN
• No. Of Pins: 64
• Package / Case: QFN
• Interface Type: I2C, JTAG, PCI, SPI
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Board Layout and Schematic Checklists—82574 GbE Controller
NC-SI
10/100/
1000Base-T
Interface
Traces
10/100/1000
Base-T Interface
Magnetic Module
(Integrated
Option)
Section
Use 10 K pull-up resistors on the
NC_SI_TXD0, NC_SI_TXD1, NC_SI_RXD0,
and NC_SI_RXD1 interfaces.
Use a 10 K pull-down resistors on the
NC_SI_TX_EN, and NC_SI_CRS_DV
interfaces.
Use a 33  series resister on the
NC_SI_CLK_IN interface near the clock
source.
Use a 22  series back-termination resistor
near the Manageability Controller (MC)
NC_SI_TXD0 and NC_SI_TXD1 interface.
If the NC-SI interface is not used tie
NC_SI_CLK_IN, NC_SI_CRS_DV, and
NC_SI_TX_EN each to ground using a 10 K
resistor.
If the NC-SI interface is not used tie
NC_SI_TXD0, NC_SI_TXD1, NC_SI_RXD0,
and NC_SI_RXD1 each to 3.3 V dc using a
10 K resistor
Design traces for 100  differential impedance
(± 20%)
Avoid highly resistive traces (for example,
avoid four mil traces longer than four inches)
If a LAN switch is used or the trace length
from the 82574 is greater than four inches. It
might be necessary to boost the voltage at the
center tap with a separate power supply to
optimize MDI performance.
Qualify magnetic modules carefully for return
loss, insertion loss, open circuit inductance,
common mode rejection, and crosstalk
isolation.
Supply 1.9 V dc to the transformer center taps
and use 0.01 F bypass capacitors. If a LAN
switch is used or the trace length from the
82574 is greater than four inches, it might be
necessary to boost the voltage at the center
tap with a separate external power supply to
optimize MDI performance.
Ensure there are no termination resistors in
the path between the 82574 and the magnetic
module.
Check Items
Ensure pull-ups are connected to auxiliary power.
Refer to the design considerations section of the
datasheet for more details.
Refer to the design considerations section of the
datasheet for more details.
This improves signal integrity by preventing reflections.
The value might need to be tuned for a specific design.
This improves reflections on the trace. The value might
need to be tuned for a specific design.
This is required so that noise on these pins does not
cause problems with device operation.
This is required so that noise on these pins does not
cause problems with device operation.
Primary requirement for 10/100/1000 Mb/s Ethernet.
Paired 50  traces do not make 100  differential. An
impedance calculator can be used to verify this.
If trace length is a problem, use thicker board
dielectrics to allow wider traces. Thicker copper is even
better than wider traces.
The boosted center tap voltage is between 1.9 V dc and
2.65 V dc and consume up to 200 mA.
Consider using a second 82574 instead of a LAN switch
and long MDI traces. It is difficult to achieve excellent
performance with long traces and analog LAN switches.
An optimization effort is required to tune the system,
the center tap voltage, and magnetics modules.
A magnetics module is critical to passing IEEE PHY
conformance tests and EMI test.
1.9 V dc at the center tap biases the 82574's output
buffers. Capacitors with low ESR should be used.
The 82574 has an internal termination network.
Remarks
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