AR# 9418

14.x Timing Closure - Suggestions on how to avoid the timing constraint missing the goal by 5% to 10%

Description

I placed a timing constraint on a path, but the constraint has errors and misses the goal by 5% to 10%. What can I do to make this timing constraint pass?

Solution


If your constraint misses its timing requirement by 5% to 10%, and the logic delay is less than 60%, you can try selecting a higher placement effort (4 or 5) and constraining the I/Os, especially data buses.

For additional suggestions and recommendations, see the following Answer Records:
- Suggestions for avoiding high fanout signals, see (Xilinx Answer 9410).
- Suggestions for state machine optimization, see (Xilinx Answer 9411).
- Suggestions for long carry logic chains, see (Xilinx Answer 9412).
- Suggestions for I/Os 3-state enable paths, see (Xilinx Answer 9413).
- Suggestions for paths through TBUFs, see (Xilinx Answer 9414).
- Suggestions for timing through irrelevant paths such as RESET or ".SR" pin, see (Xilinx Answer 9415).
- Suggestions for using multi-cycle paths, such as a path through a ".CE" pin, see (Xilinx Answer 9416).
- Suggestions for how to avoid having too many levels of logic, see (Xilinx Answer 9417).
- Suggestions for timing constraints that miss their goals by 10% to 15%, see (Xilinx Answer 9419).
AR# 9418
Date 12/15/2012
Status Active
Type General Article
Tools More Less