Agilex™ 7 Clocking and PLL User Guide: F-Series and I-Series
ID
683761
Date
11/28/2024
Public
1. Agilex™ 7 FPGA F-Series and I-Series Clocking and PLL Overview
2. F-Series and I-Series Clocking and PLL Architecture and Features
3. F-Series and I-Series Clocking and PLL Design Considerations
4. Clock Control Intel® FPGA IP Core
5. IOPLL Intel® FPGA IP Core
6. IOPLL Reconfig Intel® FPGA IP Core
7. Agilex™ 7 Clocking and PLL User Guide: F-Series and I-Series Archives
8. Document Revision History for the Agilex™ 7 Clocking and PLL User Guide: F-Series and I-Series
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
3.1. Guidelines: Clock Switchover
3.2. Guidelines: Timing Closure
3.3. Guidelines: Resetting the PLL
3.4. Guidelines: Configuration Constraints
3.5. Guidelines: I/O PLL Reconfiguration
3.6. Clocking Constraints
3.7. IP Core Constraints
3.8. Guideline: Achieving 5% Duty Cycle for fOUT_EXT ≥ 300 MHz Using tx_outclk Port from LVDS SERDES Intel® FPGA IP
6.1. Release Information for IOPLL Reconfig Intel® FPGA IP
6.2. Implementing I/O PLL Reconfiguration in the IOPLL Reconfig IP Core
6.3. IOPLL Reconfig IP Core Reconfiguration Modes
6.4. Avalon® Memory-Mapped Interface Ports in the IOPLL Reconfig IP Core
6.5. Address Bus and Data Bus Settings
6.6. Design Example
2.1.3.1.3. I/O PLL Clock Gate
You can dynamically gate each output counter of the F-Series and I-Series I/O PLL. This I/O PLL clock gate provides a useful alternative to the root clock gate. The root clock gate can gate only 1 of 7 output counters.
However, the I/O PLL clock gate is not cycle-specific. When you use the I/O PLL clock gate, expect a delay of several clock cycles between the assertion or deassertion of the clock gate and the corresponding change to the clock signal. The number of delay cycles is non-deterministic because the enable signal must be synchronized into the clock domain of the output clock, ensuring a glitch-free gate.