Intel® Quartus® Prime Standard Edition User Guide: Timing Analyzer

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ID 683068
Date 2/21/2024
Public
Document Table of Contents
Document Table of Contents x
1. Timing Analysis Introduction 2. Using the Intel® Quartus® Prime Timing Analyzer A. Intel® Quartus® Prime Standard Edition User Guides
1. Timing Analysis Introduction x
1.1. Timing Analysis Basic Concepts 1.2. Document Revision History
1.1. Timing Analysis Basic Concepts x
1.1.1. Timing Path and Clock Analysis 1.1.2. Clock Setup Analysis 1.1.3. Clock Hold Analysis 1.1.4. Recovery and Removal Analysis 1.1.5. Multicycle Path Analysis 1.1.6. Metastability Analysis 1.1.7. Timing Pessimism 1.1.8. Clock-As-Data Analysis 1.1.9. Multicorner Analysis
1.1.1. Timing Path and Clock Analysis x
1.1.1.1. The Timing Netlist 1.1.1.2. Timing Paths 1.1.1.3. Data and Clock Arrival Times 1.1.1.4. Launch and Latch Edges
1.1.5. Multicycle Path Analysis x
1.1.5.1. Multicycle Clock Hold 1.1.5.2. Multicycle Clock Setup
2. Using the Intel® Quartus® Prime Timing Analyzer x
2.1. Enhanced Timing Analysis for Intel® Arria® 10 Devices 2.2. Basic Timing Analysis Flow 2.3. Using Timing Constraints 2.4. Timing Analyzer Tcl Commands 2.5. Timing Analysis of Imported Compilation Results 2.6. Using the Intel® Quartus® Prime Timing Analyzer Document Revision History
2.2. Basic Timing Analysis Flow x
2.2.1. Step 1: Open a Project and Run the Fitter 2.2.2. Step 2: Specify Timing Constraints 2.2.3. Step 3: Specify General Timing Analyzer Settings 2.2.4. Step 4: Run Timing Analysis 2.2.5. Step 5: Analyze Timing Analysis Results
2.2.5. Step 5: Analyze Timing Analysis Results x
2.2.5.1. Timing Report Commands 2.2.5.2. Set Operating Conditions 2.2.5.3. Fmax Summary Report 2.2.5.4. Report Timing Command 2.2.5.5. Correlating Constraints to the Timing Report 2.2.5.6. Locating Timing Paths in Other Tools
2.3. Using Timing Constraints x
2.3.1. Recommended Initial SDC Constraints 2.3.2. SDC File Precedence 2.3.3. Iterative Constraint Modification 2.3.4. Creating Clocks and Clock Constraints 2.3.5. Creating I/O Constraints 2.3.6. Creating Delay and Skew Constraints 2.3.7. Creating Timing Exceptions 2.3.8. Example Circuit and SDC File
2.3.1. Recommended Initial SDC Constraints x
2.3.1.1. Create Clock (create_clock) 2.3.1.2. Derive PLL Clocks (derive_pll_clocks) 2.3.1.3. Derive Clock Uncertainty (derive_clock_uncertainty) 2.3.1.4. Set Clock Groups (set_clock_groups)
2.3.4. Creating Clocks and Clock Constraints x
2.3.4.1. Creating Base Clocks 2.3.4.2. Creating Virtual Clocks 2.3.4.3. Creating Generated Clocks (create_generated_clock) 2.3.4.4. Deriving PLL Clocks 2.3.4.5. Creating Clock Groups (set_clock_groups) 2.3.4.6. Accounting for Clock Effect Characteristics
2.3.4.1. Creating Base Clocks x
2.3.4.1.1. Automatic Clock Detection and Constraint Creation
2.3.4.2. Creating Virtual Clocks x
2.3.4.2.1. Specifying I/O Interface Uncertainty 2.3.4.2.2. I/O Interface Clock Uncertainty Example
2.3.4.3. Creating Generated Clocks (create_generated_clock) x
2.3.4.3.1. Clock Divider Example (-divide_by) 2.3.4.3.2. Clock Multiplexor Example
2.3.4.5. Creating Clock Groups (set_clock_groups) x
2.3.4.5.1. Exclusive Clock Groups (-exclusive) 2.3.4.5.2. Asynchronous Clock Groups (-asynchronous) 2.3.4.5.3. set_clock_groups Constraint Tips
2.3.4.6. Accounting for Clock Effect Characteristics x
2.3.4.6.1. Set Clock Latency (set_clock_latency) 2.3.4.6.2. Clock Uncertainty
2.3.5. Creating I/O Constraints x
2.3.5.1. Input Constraints (set_input_delay) 2.3.5.2. Output Constraints (set_output_delay)
2.3.6. Creating Delay and Skew Constraints x
2.3.6.1. Advanced I/O Timing and Board Trace Model Delay 2.3.6.2. Maximum Skew (set_max_skew) 2.3.6.3. Net Delay (set_net_delay) 2.3.6.4. Create Timing Netlist
2.3.7. Creating Timing Exceptions x
2.3.7.1. Timing Constraint Precedence 2.3.7.2. False Paths (set_false_path) 2.3.7.3. Minimum and Maximum Delays 2.3.7.4. Multicycle Paths 2.3.7.5. Multicycle Exception Examples 2.3.7.6. Delay Annotation
2.3.7.4. Multicycle Paths x
2.3.7.4.1. Common Multicycle Applications 2.3.7.4.2. Relaxing Setup with Multicycle (set_multicyle_path) 2.3.7.4.3. Accounting for a Phase Shift (-phase)
2.3.7.5. Multicycle Exception Examples x
2.3.7.5.1. Default Multicycle Analysis 2.3.7.5.2. End Multicycle Setup = 2 and End Multicycle Hold = 0 2.3.7.5.3. End Multicycle Setup = 2 and End Multicycle Hold = 1 2.3.7.5.4. Same Frequency Clocks with Destination Clock Offset 2.3.7.5.5. Destination Clock Frequency is a Multiple of the Source Clock Frequency 2.3.7.5.6. Destination Clock Frequency is a Multiple of the Source Clock Frequency with an Offset 2.3.7.5.7. Source Clock Frequency is a Multiple of the Destination Clock Frequency 2.3.7.5.8. Source Clock Frequency is a Multiple of the Destination Clock Frequency with an Offset
2.4. Timing Analyzer Tcl Commands x
2.4.1. The quartus_sta Executable 2.4.2. Collection Commands 2.4.3. Identifying the Intel® Quartus® Prime Software Executable from the SDC File
2.4.2. Collection Commands x
2.4.2.1. Wildcard Characters 2.4.2.2. Adding and Removing Collection Items 2.4.2.3. Query of Collections 2.4.2.4. Using the get_pins Command
1. Timing Analysis Introduction
2. Using the Intel® Quartus® Prime Timing Analyzer
A. Intel® Quartus® Prime Standard Edition User Guides

2.3.1.2. Derive PLL Clocks (derive_pll_clocks)

The Derive PLL Clocks (derive_pll_clocks) constraint automatically creates clocks for each output of any PLL in your design.

The constraint can generate multiple clocks for each output clock pin if the PLL is using clock switchover: one clock for the inclk[0] input clock pin, and one clock for the inclk[1] input clock pin. Specify the Create base clocks (-create_base_clocks) option to create base clocks on the inputs of the PLLs by default. By default the clock name is the same as the output clock pin name, or specify the Use net name as clock name (-use_net_name) option to use the net name. 

create_clock -period 10.0 -name fpga_sys_clk [get_ports fpga_sys_clk] \
	derive_pll_clocks

When you create PLLs, you must define the configuration of each PLL output. This definition allows the Timing Analyzer to automatically constrain the PLLs with the derive_pll_clocks command. This command also constrains transceiver clocks and adds multicycles between LVDS SERDES and user logic.

The derive_pll_clocks command prints an Info message to show each generated clock the command creates.

As an alternative to derive_pll_clocks you can copy-and-paste each create_generated_clock assignment into the .sdc file. However, if you subsequently modify the PLL setting, you must also change the generated clock constraint in the .sdc file. Examples of this type of change include modifying an existing output clock, adding a new PLL output, or making a change to the PLL's hierarchy. Use of derive_pll_clocks eliminates this requirement.

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