Intel® Quartus® Prime Standard Edition User Guide: Design Recommendations

ID 683323
Date 9/24/2018
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1.2.3.4. Optimizing Critical Timing Paths

To close timing in high speed designs, review paths with the largest timing failures. Correcting a single, large timing failure can result in a very significant timing improvement.

Review the register placement and routing paths by clicking Tools > Chip Planner. Large timing failures on high fan-out control signals can be caused by any of the following conditions:

  • Sub-optimal use of global networks
  • Signals that traverse the chip on local routing without pipelining
  • Failure to correct high fan-out by register duplication

For high-speed and high-bandwidth designs, optimize speed by reducing bus width and wire usage. To reduce wire usage, move the data as little as possible. For example, if a block of logic functions on a few bits of a word, store inactive bits in a FIFO or memory. Memory is cheaper and denser than registers, and reduces wire usage.