82575 Ethernet Controller Design Guide

4.0Frequency Control Device Design Considerations

This section provides information regarding frequency control devices, including crystals and oscillators, for use with all Intel Ethernet controllers. Several suitable frequency control devices are available; none of which present any unusual challenges in selection. The concepts documented herein are applicable to other data communication circuits, including Platform LAN Connect devices (PHYs).

The Intel Ethernet controllers contain amplifiers, which when used with the specific external components, form the basis for feedback oscillators. These oscillator circuits, which are both economical and reliable, are described in more detail in “Crystal Selection Parameters”.

The Intel Ethernet controllers also have bus clock input functionality, however a discussion of this feature is beyond the scope of this document, and will not be addressed.

The chosen frequency control device vendor should be consulted early in the design cycle. Crystal and oscillator manufacturers familiar with networking equipment clock requirements may provide assistance in selecting an optimum, low-cost solution.

4.1Frequency Control Component Types

Several types of third-party frequency reference components are currently marketed. A discussion of each follows, listed in preferred order.

4.1.1Quartz Crystal

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.

4.1.2Fixed Crystal Oscillator

A packaged fixed crystal oscillator comprises an inverter, a quartz crystal, and passive components conveniently packaged together. The device renders a strong, consistent square wave output. Oscillators used with microprocessors are supplied in many configurations and tolerances.

Crystal oscillators should be restricted to use in special situations, such as shared clocking among devices or multiple controllers. As clock routing can be difficult to accomplish, it is preferable to provide a separate crystal for each device.

For Intel Ethernet controllers, it is acceptable to overdrive the internal inverter by connecting a

25 MHz external oscillator to the XTAL1 lead, leaving the XTAL2 lead unconnected. The oscillator should be specified to drive CMOS logic levels, and the clock trace to the device should be as short as possible. Device specifications typically call for a 40% (minimum) to 60% (maximum) duty cycle and a ±50 ppm frequency tolerance.

Note: Please contact your Intel Customer Representative to obtain the most current device documentation prior to implementing this solution.

30

Page 36
Image 36
Intel 317698-001 manual Frequency Control Device Design Considerations, Frequency Control Component Types, Quartz Crystal

317698-001 specifications

The Intel 317698-001 is a prominent and highly regarded component in the realm of computer hardware. This product is part of Intel's extensive portfolio, designed primarily for enhancing computing performance, efficiency, and reliability. It is typically associated with server motherboards and is known for its robust architecture, making it ideal for enterprise-level applications.

One of the standout features of the Intel 317698-001 is its compatibility with multiple Intel processors, which provides flexibility for users looking to upgrade or configure their systems. This compatibility ensures that enterprises can choose from a range of processors according to their specific workload requirements, allowing for tailored performance enhancements.

The product is built on the foundation of advanced technologies, such as Intel's Turbo Boost and Hyper-Threading. Turbo Boost allows the processor to operate at higher frequencies than its base clock speed when demand increases, providing a significant performance boost when needed. Hyper-Threading enables multiple threads to run simultaneously on each core, which can lead to improved multitasking capabilities and more efficient resource utilization.

Memory bandwidth is another vital characteristic of the Intel 317698-001. This component supports high-speed DDR4 memory, offering increased bandwidth that is crucial for data-intensive applications. The architecture is designed to work seamlessly with ECC (Error-Correcting Code) memory, enhancing system reliability by detecting and correcting internal data corruption.

In terms of connectivity, the Intel 317698-001 features multiple PCIe lanes, supporting various expansion cards for enhanced functionality. This includes the integration of NVMe drives for faster storage solutions, which is essential for modern applications that demand quick data access and retrieval.

Security is also a priority with the Intel 317698-001, which incorporates hardware-based security features to protect data integrity and prevent unauthorized access. These features include Intel Trusted Execution Technology, which creates a secure environment for executing sensitive code.

Overall, the Intel 317698-001 stands out with its combination of performance, versatility, and security. It is an ideal choice for businesses looking to enhance their computing capabilities while ensuring system reliability and security in an increasingly data-driven world. With its robust technological foundation, it continues to play a critical role in modern computing environments.