Clocking and PLL User Guide: Agilex™ 5 FPGAs and SoCs

Download PDF
ID 813671
Date 10/07/2024
Public
Document Table of Contents
Document Table of Contents x
1. Agilex™ 5 Clocking and PLL Overview 2. Agilex™ 5 Clocking and PLL Architecture and Features 3. Agilex™ 5 Clocking and PLL Design Considerations 4. Clock Control Intel® FPGA IP Core 5. IOPLL Intel® FPGA IP Core 6. I/O PLL Reconfiguration 7. Document Revision History for the Clocking and PLL User Guide: Agilex™ 5 FPGAs and SoCs
1. Agilex™ 5 Clocking and PLL Overview x
1.1. Clock Networks Overview 1.2. PLLs Overview
2. Agilex™ 5 Clocking and PLL Architecture and Features x
2.1. Clock Networks Architecture and Features 2.2. PLLs Architecture and Features
2.1. Clock Networks Architecture and Features x
2.1.1. Clock Network Architecture 2.1.2. Clock Resources 2.1.3. Clock Control Features
2.1.1. Clock Network Architecture x
2.1.1.1. Clock Network Hierarchy 2.1.1.2. Clock Sectors 2.1.1.3. Programmable Clock Routing
2.1.3. Clock Control Features x
2.1.3.1. Clock Gating 2.1.3.2. Clock Divider
2.1.3.1. Clock Gating x
2.1.3.1.1. Root Clock Gate 2.1.3.1.2. Sector Clock Gate 2.1.3.1.3. I/O PLL Clock Gate 2.1.3.1.4. LAB Clock Gate
2.2. PLLs Architecture and Features x
2.2.1. PLL Features 2.2.2. PLL Usage 2.2.3. PLL Locations 2.2.4. PLL Architecture 2.2.5. PLL Control Signals 2.2.6. PLL Feedback Modes 2.2.7. Clock Multiplication and Division 2.2.8. Programmable Phase Shift 2.2.9. Programmable Duty Cycle 2.2.10. PLL Cascading 2.2.11. PLL Input Clock Switchover 2.2.12. PLL Reconfiguration and Dynamic Phase Shift 2.2.13. PLL Calibration
2.2.5. PLL Control Signals x
2.2.5.1. Reset 2.2.5.2. Locked
2.2.6. PLL Feedback Modes x
2.2.6.1. Direct Compensation Mode 2.2.6.2. LVDS Compensation Mode 2.2.6.3. Source Synchronous Compensation Mode 2.2.6.4. Normal Compensation Mode 2.2.6.5. Zero-Delay Buffer Mode 2.2.6.6. External Feedback Mode
2.2.11. PLL Input Clock Switchover x
2.2.11.1. Automatic Switchover 2.2.11.2. Automatic Switchover with Manual Override 2.2.11.3. Manual Clock Switchover
2.2.13. PLL Calibration x
2.2.13.1. Power-Up Calibration 2.2.13.2. User Calibration 2.2.13.3. Static Phase Error Calibration
3. Agilex™ 5 Clocking and PLL Design Considerations x
3.1. Guidelines: Clock Switchover 3.2. Guidelines: Timing Closure 3.3. Guidelines: Resetting the PLL 3.4. Guidelines: Configuration Constraints 3.5. Clocking Constraints 3.6. IP Core Constraints 3.7. Guideline: Achieving 5% Duty Cycle for fOUT_EXT ≥ 300 MHz Using tx_outclk Port from LVDS SERDES Intel® FPGA IP
4. Clock Control Intel® FPGA IP Core x
4.1. Release Information for Clock Control Intel® FPGA IP 4.2. Clock Control IP Core Parameters 4.3. Clock Control IP Core Ports and Signals
5. IOPLL Intel® FPGA IP Core x
5.1. Release Information for IOPLL Intel® FPGA IP Core 5.2. IOPLL IP Core Parameters 5.3. IOPLL IP Core Ports and Signals
5.2. IOPLL IP Core Parameters x
5.2.1. IOPLL IP Core Parameters - PLL Tab 5.2.2. IOPLL IP Core Parameters - Settings Tab 5.2.3. IOPLL IP Core Parameters - Cascading Tab 5.2.4. IOPLL IP Core Parameters - Advanced Parameters Tab
6. I/O PLL Reconfiguration x
6.1. Release Information for EMIF Calibration IP 6.2. Implementing HSIO I/O PLL Reconfiguration using EMIF Calibration IP 6.3. Implementing HVIO I/O PLL Reconfiguration 6.4. Reconfiguration Guideline for I/O PLLs 6.5. Axilite Interface Ports in the EMIF Calibration IP 6.6. Address Bus and Data Bus Settings 6.7. Design Example
6.2. Implementing HSIO I/O PLL Reconfiguration using EMIF Calibration IP x
6.2.1. Setting Up the IOPLL Intel® FPGA IP 6.2.2. Setting Up the EMIF Calibration IP 6.2.3. Connectivity Between IOPLL and EMIF Calibration IP
6.3. Implementing HVIO I/O PLL Reconfiguration x
6.3.1. Setting Up the IOPLL Intel® FPGA IP 6.3.2. Read and Write Operations
6.4. Reconfiguration Guideline for I/O PLLs x
6.4.1. Enabling Reconfiguration for The Desired I/O PLL 6.4.2. Clearing off Calibration Statuses 6.4.3. Reconfiguring The I/O PLL 6.4.4. Recalibration of I/O PLL 6.4.5. Clock Gating (Optional)
6.6. Address Bus and Data Bus Settings x
6.6.1. Divide Settings and the Corresponding Data Bit Setting for Reconfiguration 6.6.2. Data Bus Setting for Clock Gating Reconfiguration 6.6.3. Data Bus Setting For Charge Pump Current
6.7. Design Example x
6.7.1. Reconfiguration Option: Reconfiguration Through EMIF Calibration IP 6.7.2. Reconfiguration Option: Reconfiguration Through HVIO Interfaces 6.7.3. Reconfiguration Option: Clock Gating Reconfiguration
1. Agilex™ 5 Clocking and PLL Overview
2. Agilex™ 5 Clocking and PLL Architecture and Features
3. Agilex™ 5 Clocking and PLL Design Considerations
4. Clock Control Intel® FPGA IP Core
5. IOPLL Intel® FPGA IP Core
6. I/O PLL Reconfiguration
7. Document Revision History for the Clocking and PLL User Guide: Agilex™ 5 FPGAs and SoCs

2.1.1.3. Programmable Clock Routing

The Quartus® Prime software automatically configures the clock switch multiplexer, clock tap multiplexer, SCLK multiplexer, and row clock multiplexers to generate skew-balanced clock trees. The resulting routing path distributes the signal from the clock source to all target destinations in one or more clock sectors.

The Quartus® Prime software creates efficiently balanced clock trees of various sizes, ranging from a single clock sector to the entire device, as shown in the following figure. By default, the Quartus® Prime software automatically determines the size and location of the clock tree. Alternatively, you can directly constrain the clock tree size and location by using either a Clock Region Assignment or Logic Lock Regions.

The total insertion delay for the clock network depends on the number of clock resources needed to implement the clock tree, increasing with the distance of the furthest clock destination from the signal source. As delay increases, the worst-case skew for crossing clock networks using different clock tree branches grows, potentially degrading the maximum performance. For very high-speed clock signals, it is advantageous to follow these guidelines:

  • Reduce the number of clock networks driven, which reduces the clock skew.
  • Reduce the distance between the clock source and the furthest destination, which reduces both clock skew and total clock insertion delay.
Figure 4. Examples of Clock Networks Sizes Using Agilex™ 5 Device Programmable Clock Routing
Level Two Title