AN 766: Intel® Stratix® 10 Devices, High Speed Signal Interface Layout Design Guideline
ID
683132
Date
3/12/2019
Public
Intel® Stratix® 10 Devices and Transceiver Channels
PCB Stackup Selection Guideline
Recommendations for High Speed Signal PCB Routing
FPGA Fan-out Region Design
CFP2/CFP4 Connector Board Layout Design Guideline
QSFP+/zSFP/QSFP28 Connector Board Layout Design Guideline
SMA 2.4-mm Layout Design Guideline
Tyco/Amphenol Interlaken Connector Design Guideline
Electrical Specifications
Document Revision History for AN 766: Intel® Stratix® 10 Devices, High Speed Signal Interface Layout Design Guideline
Option 1: Via-In-Pad Topology
Option 2: Dog-bone with GND Cutout at BGA Pad Topology
Option 3: Micro-via Topology
GND Cutout Under BGA Pads in Fan-out Configuration
Comparison of Dog-bone with GND Cutout Under the BGA and Via-in-Pad Configurations
Trace Shape Routing at the BGA Void Area (Tear Drop Configuration)
PCB Design Guidelines for Channels Using the 2.4 mm Connector
Observe the following guidelines when designing for channels using the 2.4 mm connector:
- Refer to PCB Stackup Selection Guideline chapter for the selection of stackup and routing layers.
- Intel recommends a routing trace impedance of 95Ω loosely differential, or 47.5 Ω single-ended. Refer to FPGA Fan-out Region chapter for break-out routing at the FPGA.
- Use the minimum routing length possible to minimize insertion loss and crosstalk.
- Refer to the AC coupling layout design guide in AC Coupling Capacitor Layout and Optimization Guidelines chapter, because all RX paths require AC capacitors.
- Match the length (less than 2 ps) for all TX and RX paths if required. Refer to Recommendations for High Speed Signal PCB Routing chapter for the length matching strategies at the FPGA.
- Use a back-drill for all transceiver signal vias.
- The Molex connector and cutout are standard recommendations made by Molex. This is a surface-mounted connector, and there is always a back-drill for the signal vias for transferring signals from the top layer to the inner layers.