Intel 440GX manual Design Methodology, Motherboard Layout and Routing Guidelines

Motherboard Layout and Routing Guidelines

2.3.7Design Methodology

Intel recommends using the following design methodology when designing systems based on one or two Intel® Pentium® II processors and one Intel® 440GX AGPset. The methodology evolved from Intel’s experience developing and validating high speed GTL+ bus designs for the Intel ® Pentium® Pro and Intel® Pentium® II processors.

The methodology provides a step-by-step process which is summarized in Figure 2-12. The process begins with an initial timing analysis and topology definition. Timing and topology recommendations are included in this section. The heart of the methodology is structured around extensive simulations and analysis prior to board layout. This represents a significant departure from traditional design methods. The pre-layout simulations provide a detailed picture of the working “solution space” for the design. By basing the board layout guidelines on the solution space, the need to iterate between layout and post-layout simulation is minimized. The methodology includes specific recommendations for analytical techniques and simulation conditions. Following layout, simulation with the extracted design database is used to verify that the design meets flight time and signal quality requirements prior to building hardware. Finally, validation verifies that the system meets 100 MHz timing and signal quality requirements with actual hardware.

Intel®440GX AGPset Design Guide 2-11