PCB Design Guidelines: Agilex™ 3 FPGAs and SoCs

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ID 853726
Date 8/20/2025
Public
Document Table of Contents
Document Table of Contents x
1. Overview 2. BGA Footprint and Land Pattern 3. General PCB Design Considerations 4. VPBGA PCB Routing Guidelines 5. MBGA PCB Routing Guidelines 6. EMIF PCB Routing Guidelines (VPBGA and MBGA) 7. MIPI Interface Layout Design Guidelines (VPBGA and MBGA) 8. True Differential I/O Interface PCB Routing Guidelines 9. Power Distribution Network Design Guidelines 10. Document Revision History for the PCB Design Guidelines: Agilex™ 3 FPGAs and SoCs
1. Overview x
1.1. Agilex™ 3 FPGAs and SoCs Packages
2. BGA Footprint and Land Pattern x
2.1. Metal-Defined Board Pad 2.2. Spoked Pad 2.3. Wide Trace Metal-Defined Pad 2.4. Solder Mask-Defined Pad 2.5. Recommended Land Patterns
3. General PCB Design Considerations x
3.1. Impedance Tolerances 3.2. Reference Planes 3.3. Layer Assignment 3.4. Via Drill Size 3.5. Fiber Weave 3.6. PCB Traces 3.7. PCB Vias 3.8. AC Coupling Capacitors 3.9. Other Considerations
3.6. PCB Traces x
3.6.1. Zig-Zag Routing 3.6.2. Image Rotation
4. VPBGA PCB Routing Guidelines x
4.1. Pin Distribution and Ball Pitches 4.2. Fan-Out and Routing Strategy 4.3. Power Pins
5. MBGA PCB Routing Guidelines x
5.1. Typical Design Rules For Type-IV HDI in a 0.5 mm MBGA 5.2. HSSI Breakout 5.3. EMIF Breakout 5.4. GTS Transceiver PCIe* 3.0 Interface Design Guidelines 5.5. GTS Transceiver Ethernet 10G NRZ Interface Design Guidelines 5.6. DisplayPort Connectors 5.7. HDMI Connectors
5.4. GTS Transceiver PCIe* 3.0 Interface Design Guidelines x
5.4.1. Channel Recommendations 5.4.2. General Guidelines for PCIe* 3.0 Interface 5.4.3. PCIe* Add-In Card Edge Finger
5.5. GTS Transceiver Ethernet 10G NRZ Interface Design Guidelines x
5.5.1. Channel Recommendations 5.5.2. General Guidelines for Ethernet Interface 5.5.3. Quad Small Form-factor Pluggable and Small Form-factor Pluggable Connector Routing
6. EMIF PCB Routing Guidelines (VPBGA and MBGA) x
6.1. General DDR Signal Routing Guideline on PCB 6.2. General Notes for EMIF Routing Guidelines Table 6.3. LPDDR4 Interface Design Guidelines 6.4. LPDDR4 Simulation Strategy
6.1. General DDR Signal Routing Guideline on PCB x
6.1.1. FPGA DDR Break Out Routing 6.1.2. DRAM Break Out in Layout Routing 6.1.3. Ground Plane and Return Path
6.3. LPDDR4 Interface Design Guidelines x
6.3.1. LPDDR4 Memory Down Topology (Up to 32-bits Interface) 6.3.2. Tables for Comprehensive Routing Guidelines for Each LPDDR4 Signal
8. True Differential I/O Interface PCB Routing Guidelines x
8.1. True Differential I/O Specifications
9. Power Distribution Network Design Guidelines x
9.1. Agilex™ 3 Power Distribution Network Design Guidelines Overview 9.2. Power Delivery Overview 9.3. Board Power Delivery Network Recommendations 9.4. Board LC Recommended Filters for Noise Reduction in Combined Power Delivery Rails 9.5. PCB PDN Design Guideline for Unused GTS Transceiver 9.6. PCB Voltage Regulator Recommendation for PCB Power Rails 9.7. Board PDN Simulations 9.8. Agilex™ 3 Device Family PDN Design Summary
9.2. Power Delivery Overview x
9.2.1. Power Architecture 9.2.2. Rail Merger Requirements 9.2.3. Power Rails Specification 9.2.4. Decoupling Capacitors Recommendation
9.2.1. Power Architecture x
9.2.1.1. Power Budget 9.2.1.2. Power Tree
9.2.3. Power Rails Specification x
9.2.3.1. Power Nets 9.2.3.2. Power Rails Tolerance 9.2.3.3. Power Nets and Transient Specifications
9.2.3.1. Power Nets x
9.2.3.1.1. Agilex™ 3 Package Power Nets and Subsystems Details
9.2.4. Decoupling Capacitors Recommendation x
9.2.4.1. Agilex™ 3 FPGA Packages Board-Level Decoupling Capacitors Summary 9.2.4.2. Agilex™ 3 GTS Transceiver Board-Level Decoupling Capacitors Summary
9.3. Board Power Delivery Network Recommendations x
9.3.1. Board Decoupling Capacitors Guide 9.3.2. FPGA Core Fabric VCC Voltage Regulator Selection 9.3.3. Remote Sense Connections 9.3.4. Load Line Requirements 9.3.5. VCC Core Board Current Slew Rate
9.4. Board LC Recommended Filters for Noise Reduction in Combined Power Delivery Rails x
9.4.1. GTS Transceiver Rail Board Connection and LC Filter Recommendation Under Noisy Voltage Regulator
9.5. PCB PDN Design Guideline for Unused GTS Transceiver x
9.5.1. PDN Design Guideline for Unused GTS Transceiver
1. Overview
2. BGA Footprint and Land Pattern
3. General PCB Design Considerations
4. VPBGA PCB Routing Guidelines
5. MBGA PCB Routing Guidelines
6. EMIF PCB Routing Guidelines (VPBGA and MBGA)
7. MIPI Interface Layout Design Guidelines (VPBGA and MBGA)
8. True Differential I/O Interface PCB Routing Guidelines
9. Power Distribution Network Design Guidelines
10. Document Revision History for the PCB Design Guidelines: Agilex™ 3 FPGAs and SoCs

6.1. General DDR Signal Routing Guideline on PCB

Altera recommends routing all data signals within a specific group on the same layer. This section provides both stripline and microstrip routing guidelines for all supported EMIF interfaces and topologies.

Route the data group signals (DQ, DM and DQS signals) on shallow layers—stripline or microstrip line. For better performance, use the shortest Z-height via transitions to avoid vertical crosstalk.

Long via stubs affects the channel ISI, however the impact of ISI is less than the impact of crosstalk for the maximum data rate performance.

Figure 28. Case A Routing is Suggested for Data Group Signals Over Case B

To minimize horizontal crosstalk between signals on the same layer, Altera recommends maintaining adequate signal trace–to–trace (edge to edge) space. Keep a minimum spacing of 3× H2 separation distance for inner layer as shown in the following figure. Certain signals within the same group can have smaller spacing, such as DQ to DQ. For more details about the spacing requirement, refer to the respective routing guide sections for each signal group.

Figure 29. Minimum Trace-to-Trace Separation Distance

Section Content
FPGA DDR Break Out Routing
DRAM Break Out in Layout Routing
Ground Plane and Return Path

2 'H' is the dielectric thickness to the closest reference plane.
Level Two Title