: Instructions for create_clock and create_generated_clock to identify primary oscillators and internal clock dividers.
Critical for DSP slices or complex arithmetic units where data has two or more clock cycles to stabilize. 5. Optimization Strategies
# Create a divide-by-2 clock generated from SYS_CLK at register output 'clk_div_reg/Q' create_generated_clock -name DIV_CLK \ -source [get_ports clk_in] \ -divide_by 2 \ [get_pins clk_div_reg/Q] Use code with caution. Clock Properties: Skew, Jitter, and Latency synopsys timing constraints and optimization user guide 2021
The 2021 guide focuses on Synopsys Design Constraints (SDC). This is the language used to write the rules. Here are the main topics the guide covers. 1. Setting Up Clocks
Modern designs have multiple operating modes (e.g., turbo mode vs. power-saving mode). Synopsys tools in 2021 allow for , ensuring that fixing a violation in one scenario does not violate timing in another. 4. Best Practices for 2021 Timing Closure Here are the main topics the guide covers
# Define a divide-by-2 clock generated at the output of a flip-flop create_generated_clock -name DIV_CLK \ -source [get_ports sys_clk] \ -divide_by 2 \ [get_pins clk_div_reg/Q] Use code with caution. Virtual Clocks
to move registers across combinational logic for better performance without changing functional behavior. Machine Learning Integration turbo mode vs.
One of the major themes in the 2021 documentation is the reduction of "false violations"—timing violations that aren't actually bottlenecks, often caused by incorrect or incomplete SDC files. Key Optimization Steps
Applying false_path and multicycle_path constraints to focus optimization on critical paths. Optimization Highlights