Synopsys Timing Constraints and Optimization User Guide 2021: Achieving Optimal PPA
Moving registers across logic blocks to balance path delays.
: Duplicating a driver cell to split a high-fanout load into multiple independent paths. Area and Power Optimization synopsys timing constraints and optimization user guide 2021
During pre-layout synthesis (Design Compiler), clocks are modeled as , meaning they distribute to all registers with zero delay. During post-layout implementation (IC Compiler II), after the clock tree is physically built, clocks are switched to propagated to calculate actual network delays.
Swapping a standard cell for a larger version with higher drive strength to fix setup time, or a smaller version to reduce power. Do not just look at violations; understand the
Use report_timing extensively. Do not just look at violations; understand the path's structure.
Note: This text is a synthesized technical summary based on the public documentation structure of Synopsys tools. For exact command syntax and legal usage, refer to the official PDF available via a valid Synopsys SolvNet+ subscription. 3. Synopsys Optimization Techniques and Methodologies
While the core SDC syntax remains consistent, the 2021 user guide places increased emphasis on:
To efficiently achieve timing closure, engineers should follow these best practices:
# Create a 500 MHz clock with a 50% duty cycle on port 'clk' create_clock -name sys_clk -period 2.0 [get_ports clk] Use code with caution. Generated Clocks
Warning: Avoid overusing set_false_path . It can hide real timing violations. 3. Synopsys Optimization Techniques and Methodologies