lu82562ex Intel Corporation, lu82562ex Datasheet - Page 15

• Manufacturer Part Number: lu82562ex
• Description: Dual Footprint
• Manufacturer: Intel Corporation

3.0
3.1
3.1.1
Table 5. Crystal Parameters
General Design Considerations for Ethernet Controllers
Ethernet Component Design Guidelines
These sections provide recommendations for selecting components and connecting special pins.
The main design elements are the 82562EZ(EX) Platform LAN Connect device or the
82547GI(EI) Gigabit Ethernet Controller, an integrated magnetics module with RJ-45 connector,
and a crystal clock source.
These recommendations apply to all designs, 10/100 or 10/100/1000 Mb/s.
Follow good engineering practices with respect to unused inputs by terminating them with pull-up
or pull-down resistors, unless the data sheet, design guide or reference schematic indicates
otherwise. Do not attach pull-up or pull-down resistors to any balls identified as No Connect.
These devices may have special test modes that could be entered inadvertently.
Crystal Selection Parameters
Quartz crystals are generally considered to be the mainstay of frequency control components due to
their low cost and ease of implementation. They are available from numerous vendors in many
package types and with various specification options.
All crystals used with Intel
angle at which the unit is sliced with respect to the long axis of the quartz stone.
Table 5
parameters listed are described in the following subsections.
Equivalent Series Resistance
Frequency Tolerance
Temperature Stability
Nominal Frequency
lists the crystal electrical parameters and provides suggested values for typical designs. The
Shunt Capacitance
Load Capacitance
Calibration Mode
Vibration Mode
Drive Level
Parameter
Aging
®
Ethernet controllers are described as “AT-cut”, which refers to the
Fundamental
25,000 MHz at 25
Parallel
6 pF maximum
0.5 mW maximum
±5 ppm per year maximum
• ±30 ppm recommended; ±50 ppm across the entire operating
• ±30 ppm required for the 82547GI(EI)
• ±50 ppm at 0
• ±30 ppm at 0
• 16 pF to 20 pF
• 18 pF required for the 82547GI(EI)
• 50 Ω maximum
• 10 Ω maximum required for the 82547GI(EI)
temperature range as required by IEEE specifications
82562EZ(EX)/82547GI(EI) Dual Footprint Design Guide
°
°
°
C to 70
C to 70
C (required)
Suggested Value
°
°
C
C required for the 82547GI(EI)
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