AN 766: Intel® Stratix® 10 Devices, High Speed Signal Interface Layout Design Guideline

ID 683132
Date 3/12/2019
Public
Document Table of Contents

AC Coupling Capacitor Layout and Optimization Guidelines

It is possible to use both the 0402 and 0201 capacitor sizes on boards as AC coupling capacitors on transceiver links.

Figure 38. AC Capacitor Placement and GND Cutout on PCB with Stripline Routing on Both Ends Structural detail where trace routing is stripline and the AC capacitor is mounted on the top or bottom layers.

The structural detail includes the following specifications:

  • 10 mil drill hole and 20 mil pad
  • The cap is mounted on the top layer and the trace breakout is routed on layer 7
  • 10 mil stub length
  • 0201 capacitor size copper block
    • 24 mil x 12 mil x 12 mil
  • 0402 capacitor size copper block
    • 40 mil x 20 mil x 14 mil

The board stack-up configuration includes the following specifications:

  • 24 layers and a thickness of 117 mil
  • 8 signal layers, 4 PWR lanes
  • Megtron6 material