General-Purpose I/O User Guide: Agilex™ 3 FPGAs and SoCs
ID
847266
Date
8/04/2025
Public
1. Agilex™ 3 General-Purpose I/O Overview
2. Agilex™ 3 HSIO Banks
3. Agilex™ 3 HVIO Banks
4. Agilex™ 3 HPS I/O Banks
5. Agilex™ 3 SDM I/O Banks
6. Agilex™ 3 I/O Troubleshooting Guidelines
7. GPIO FPGA IP
8. Programmable I/O Features Description
9. Document Revision History for the General-Purpose I/O User Guide: Agilex™ 3 FPGAs and SoCs
2.5.1. I/O Standard Placement Restrictions for True Differential I/Os
2.5.2. Placement Restrictions for True Differential and Single-Ended I/O Standards in the Same or Adjacent HSIO Bank
2.5.3. VREF Sources and Input Standards Grouping
2.5.4. HSIO Pin Restrictions for External Memory Interfaces
2.5.5. RZQ Pin Requirement
2.5.6. I/O Standards Implementation Based on VCCIO_PIO Voltages
2.5.7. I/O Standard Selection and I/O Bank Supply Compatibility Check
2.5.8. Simultaneous Switching Noise
2.5.9. HPS Shared I/O Requirements
2.5.10. Clocking Requirements
2.5.11. Clock Restrictions for GPIO Interfaces
2.5.12. SDM Shared I/O Requirements
2.5.13. Unused Pins
2.5.14. VCCIO_PIO Supply for Unused HSIO Banks
2.5.15. HSIO Pins During Power Sequencing
2.5.16. Drive Strength Requirement for HSIO Input Pins
2.5.17. Maximum DC Current Restrictions
2.5.18. 1.05 V, 1.1 V, or 1.2 V I/O Interface Voltage Level Compatibility
2.5.19. Connection to True Differential Signaling Input Buffers During Device Reconfiguration
2.5.20. Implementing a Pseudo Open Drain
2.5.21. Allowed Duration for Using RT OCT
2.5.22. Single-Ended Strobe Signal Differential Pin Pair Restriction
2.5.23. Implementing SLVS-400 or DPHY I/O Standard with 1.1 V VCCIO_PIO
8.2. Programmable De-Emphasis
To compensate for signal degradation over long transmission path, you can alter the signal amplitude through the programmable de-emphasis feature.
Item | Description |
---|---|
Availability | Available for the following I/O standards:
|
Implementation | Two-tap de-emphasis implementation:
|
Behavior | If turned on, the feature attenuates the I/O signal height, when the symbol is longer than 1 UI. |
Types |
|
Recommendations |
|
Figure 52. De-Emphasis Off: Signal Attenuation for Supported I/O Standards
Figure 53. Constant Impedance De-Emphasis: Signal Attenuation for Supported I/O Standards
Figure 54. Low Power De-Emphasis: Signal Attenuation for Supported I/O Standards