Intel Agilex® 7 General-Purpose I/O User Guide: F-Series and I-Series
ID
683780
Date
7/04/2023
Public
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1. Intel Agilex® 7 F-Series and I-Series General-Purpose I/O Overview
2. Intel Agilex® 7 F-Series and I-Series GPIO Banks
3. Intel Agilex® 7 F-Series and I-Series HPS I/O Banks
4. Intel Agilex® 7 F-Series and I-Series SDM I/O Banks
5. Intel Agilex® 7 F-Series and I-Series I/O Troubleshooting Guidelines
6. Intel Agilex® 7 F-Series and I-Series General-Purpose I/O IPs
7. Programmable I/O Features Description
8. Documentation Related to the Intel Agilex® 7 General-Purpose I/O User Guide: F-Series and I-Series
9. Document Revision History for the Intel Agilex® 7 General-Purpose I/O User Guide: F-Series and I-Series
2.5.1. VREF Sources and VREF Pins
2.5.2. I/O Standards Implementation Based on VCCIO_PIO Voltages
2.5.3. OCT Calibration Block Requirement
2.5.4. I/O Pins Placement Requirements
2.5.5. I/O Standard Selection and I/O Bank Supply Compatibility Check
2.5.6. Simultaneous Switching Noise
2.5.7. Special Pins Requirement
2.5.8. External Memory Interface Pin Placement Requirements
2.5.9. HPS Shared I/O Requirements
2.5.10. Clocking Requirements
2.5.11. SDM Shared I/O Requirements
2.5.12. Unused Pins
2.5.13. Voltage Setting for Unused GPIO Banks
2.5.14. GPIO Pins During Power Sequencing
2.5.15. Drive Strength Requirement for GPIO Input Pins
2.5.16. Maximum DC Current Restrictions
2.5.17. 1.2 V I/O Interface Voltage Level Compatibility
2.5.18. GPIO Pins for the Avalon® Streaming Interface Configuration Scheme
2.5.19. Maximum True Differential Signaling Receiver Pairs Per I/O Lane
6.1.1. Release Information for GPIO Intel® FPGA IP
6.1.2. Generating the GPIO Intel® FPGA IP
6.1.3. GPIO Intel® FPGA IP Parameter Settings
6.1.4. GPIO Intel® FPGA IP Interface Signals
6.1.5. GPIO Intel® FPGA IP Architecture
6.1.6. Verifying Resource Utilization and Design Performance
6.1.7. GPIO Intel® FPGA IP Timing
6.1.8. GPIO Intel® FPGA IP Design Examples
7.1. Programmable Pre-Emphasis
The VOD setting and the output impedance of the driver set the output current limit of a high-speed transmission signal. At a high frequency, the slew rate may not be fast enough to reach the full VOD level before the next edge, producing pattern-dependent jitter. With pre-emphasis, the output current is boosted momentarily during switching to increase the output slew rate.
Pre-emphasis increases the amplitude of the high-frequency component of the output signal and thus helps to compensate for the frequency-dependent attenuation along the transmission line. The overshoot introduced by the extra current happens only during a change of state switching to increase the output slew rate and does not ring, unlike the overshoot caused by signal reflection. The amount of pre-emphasis required depends on the attenuation of the high-frequency component along the transmission line.
Figure 52. Programmable Pre-emphasisThis figure shows the true differential output with pre-emphasis.