Synopsys Timing Constraints And Optimization User Guide 2021

# Create a divide-by-2 clock generated by a flip-flop 'clk_div_reg' create_generated_clock -name gen_clk -source [get_ports clk] -divide_by 2 [get_pins clk_div_reg/Q] Use code with caution. Virtual Clocks

Defines the time a clock pulse takes to travel from its source (e.g., an oscillator) to the clock definition point (source latency) or from the definition point to the register clock pins (network latency).

Emphasis on developing comprehensive constraints earlier in the design cycle to reduce iterations between synthesis and place-and-route (P&R). synopsys timing constraints and optimization user guide 2021

Understanding the Synopsys Timing Constraints and Optimization User Guide 2021

: Moving registers across combinational logic boundaries to balance path delays without changing the design’s functionality. # Create a divide-by-2 clock generated by a

Modern System-on-Chips (SoCs) rely heavily on internal clock dividers, multipliers, and Phase-Locked Loops (PLLs). Instead of treating these as standalone primary clocks, they must be constrained as generated clocks to maintain a phase relationship with their source clock.

Synopsys engines optimize designs based on a weighted priority queue called the cost function. By default, the optimization priorities are ranked as follows: Synopsys engines optimize designs based on a weighted

Synopsys tools break down a netlist into discrete timing paths. Every timing path consists of:

: set_max_area , set_max_dynamic_power , and set_max_leakage_power are used to drive the tool toward smaller or more efficient implementations.

Max Input Delay=Tclk_to_q_ext+Tpcb_trace_maxMax Input Delay equals cap T sub clk_to_q_ext end-sub plus cap T sub pcb_trace_max end-sub

Virtual clocks exist only in the timing environment and do not map to a physical port or pin in the netlist. They serve as a reference point for bounding input and output delays.