Quartus® Prime Pro Edition User Guide: PCB Design Tools

ID 683768
Date 9/30/2024
Public
Document Table of Contents

1.5.13.2. Hold Time Analysis

Intel recommends performing worst-case hold time analysis using the fast corner models, which use fast transistors, high voltage, and low temperature. This involves modifying the SPICE decks to select the correct temperature option, change the supply voltage sources, and load the correct fast transistor models. The values of these parameters are located in the header comment section of the corresponding simulation deck files.

For a truly worst-case analysis, combine the HSPICE Writer hold time analysis results with the Quartus® Prime software fast timing model. This requires that you change the double-counting compensation circuitry in the simulations files to also simulate the fast process corners, as this is what the Quartus® Prime software uses for the fast timing model.

Note: This method of hold time analysis is recommended only for globally synchronous buses. Do not apply this method of hold-time analysis to source synchronous buses. This is because the source synchronous clocking scheme is designed to cancel out some of the PVT timing effects. If this is not taken into account, the timing results are not accurate. Proper source synchronous timing analysis is beyond the scope of this document.