Designing for DVI

1
Designing for DVI

• General Applications Considerations

2
Design Issues to Consider

• Layout Recommendations
• Power supply considerations
• EMC considerations

3
Layout Recommendations

• Route differential pairs together

• Avoid excessive or asymmetric vias

4
Layout Recommendations (contd)

• Series damping resistors on data, clock, control
  signal inputs to TX

GPU

• Reduces signal ringing, noise

5
Layout Recommendations (contd)

• Four layer PCB
• Solid ground plane

Signal GND

6
Layout Considerations (contd)
High Emissions
GND Plane
7
Power Supply Considerations

• Voltage regulator on TX PVCC supply

Switch-mode Power Supply
PVCC, PVCC2
5V
3.3V
Switching Noise 45-60KHz

• Switching noise can cause PLL jitter
• VREG greatly reduces supply noise

8
EMC Considerations

• Even though PanelLink operates at over 1GHz, most
  emissions are still caused by parallel data
• Some high frequency emissions near 1GHz are
  possible, but are related to mechanical contact

9
EMC Considerations Data Lines

• Damping resistors, short data path

Minimize Length
10
EMC Considerations Ground Contact

• Good, broad contact between connector shells and
  the I/O bracket
• Broad contact between the I/O bracket and the
  system chassis
• Good 360o contact between connector shell and
  cable shield
• Good contact between motherboard GND and chassis
• Helps with high frequency emissions

11
EMC Considerations Ground Contact

• The chassis is the common GND reference
• Do not have floating grounds

PCB GND 2
PCB GND 2
Monitor PCB GND
PCB GND 1
Shielding
Shielding
Host Chassis
12
Ground Contact Example
PCB 2
Signal
GND (Return)
Cable Shield
PCB 1
PCB 3
Main Chassis
Remote Chassis

360
Clamps
or Connector
Shells
Shielding
Shielding
13
Summary

• Voltage regulator strongly recommended on TX PVCC
• Damping resistors on all parallel data lines
• Improves signal integrity and EMI
• Solid ground plane
• Use chassis as common GND reference

14
Conclusion

• PanelLink is very robust, but is still a
  high-speed gigabit serial link
• Higher data rate than gigabit ethernet
• Reference schematics provided
• Silicon Image is the leader in experience and
  knowledge of this technology
• Applications knowledge
• Local and factory support
• Production and testing