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Chapter 6

Special Design Considerations

This chapter describes several design considerations to consider when designing with the Xilinx SPI-4.2 Lite core:

Clocking implementations

Multiple core implementations

Sink Clocking Options

The Sink core supports two clocking implementations: embedded clocking and user clocking. The embedded clocking configuration provides a complete solution with the clock circuitry embedded within the Sink core. The user clocking configuration allows the clocking scheme to be implemented external to the Sink core. This enables the user to craft a custom clocking solution. The embedded and user clocking configurations are described in detail below.

Embedded Clocking

The embedded clocking configuration contains the clocking logic internal to the core. The embedded clocking option always uses global clocking distribution. The implementation of the embedded clocking option is illustrated in Figure 6-1. Because all global clocks are implemented differentially, this clocking scheme also minimizes duty-cycle distortion.

Note that the inverter used to generate RDClk180_GP will be absorbed into the DDR flip- flops. Table 6-1provides the clocking resource count for the embedded clocking configuration.

Table 6-1:Sink Core Embedded Clocking Resources

Clocking Distribution

BUFR

BUFG

DCM

 

 

 

 

Global Clocking

0

1

1

 

 

 

 

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UG181 June 27, 2008

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Xilinx UG181 manual Special Design Considerations, Sink Clocking Options, Embedded Clocking

UG181 specifications

Xilinx UG181 refers to the User Guide for the Xilinx 7 Series FPGAs, which offers a comprehensive overview of the architecture, capabilities, and features of these powerful field-programmable gate arrays (FPGAs). Designed to cater to a wide range of applications, Xilinx 7 Series FPGAs are widely adopted in industries such as telecommunications, automotive, aerospace, and consumer electronics.

One of the main features of the Xilinx 7 Series FPGAs is their use of advanced 28nm technology, which enables them to achieve high performance while maintaining low power consumption. This fine process technology not only ensures better power efficiency but also allows for increased logic density. The 7 Series includes several families, such as Artix-7, Kintex-7, and Virtex-7, each tailored for specific application demands ranging from cost-sensitive solutions to high-performance data processing.

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Finally, Xilinx has made significant strides in development tools for 7 Series FPGAs, providing a robust ecosystem for design engineers. With design suites such as Vivado and SDK, users benefit from a comprehensive platform for deciding, simulating, and implementing designs efficiently. The combination of advanced hardware capabilities and powerful software tools solidifies the position of Xilinx 7 Series FPGAs as a preferred choice for custom digital hardware design across various industries.