1

Designing for DVIDesigning for DVI

General Applications ConsiderationsGeneral Applications Considerations

2

Design Issues to ConsiderDesign Issues to Consider

• Layout Recommendations

• Power supply considerations

• EMC considerations

• Layout Recommendations

• Power supply considerations

• EMC considerations

3

Layout RecommendationsLayout Recommendations

• Route differential pairs together• Route differential pairs together

• Avoid excessive or asymmetric vias• Avoid excessive or asymmetric vias

4

Layout Recommendations (cont’d)Layout Recommendations (cont’d)

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

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

• Reduces signal ringing, noise• Reduces signal ringing, noise

GPU

5

Layout Recommendations (cont’d)Layout Recommendations (cont’d)

• Four layer PCB- Solid ground plane

• Four layer PCB- Solid ground plane

Common-ModeCurrent

ICSignal

GND

ICSignal Lines

Cut in GND or poor HF contact

6

GND Plane

Return Current

Signal

Layout Considerations (cont’d)Layout Considerations (cont’d)

Return Current

GND Plane

High Emissions

Trace

Signal

Low Emissions

7

Power Supply ConsiderationsPower Supply Considerations

• Voltage regulator on TX PVCC supply• Voltage regulator on TX PVCC supply

Switch-modePower Supply

PVCC, PVCC2+5V

+3.3V

Switching Noise~45-60KHz

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

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

8

EMC ConsiderationsEMC 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

• 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 LinesEMC Considerations: Data Lines

• Damping resistors, short data path• Damping resistors, short data path

MinimizeLength

10

EMC Considerations: Ground ContactEMC Considerations: Ground Contact

Good, broad contact between connector shells and the I/O bracketBroad contact between the I/O bracket and the system chassisGood 360

o contact between connector shell and cable shield

Good contact between motherboard GND and chassisHelps with high frequency emissions

Broad contactBetween connectorAnd Bracket

Good contact betweenShield and connectorShell

Solid contact betweenBracket and chassis

11

EMC Considerations: Ground ContactEMC Considerations: Ground Contact

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

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

PCB GND 2PCB GND 2Signal GND/RTN

MonitorPCB GND

MonitorPCB GND

ShieldingShieldingShieldingShielding HostChassis

HostChassis

PCB GND 2PCB GND 2

PCB GND 1PCB GND 1

Cable Shield

DisplayChassis

DisplayChassis

12

Ground Contact: ExampleGround Contact: Example

Cable Shield

360 Clampsor ConnectorShells

Main Chassis Remote Chassis

PCB 1 PCB 3

Shielding

PCB 2

Shielding

Signal &GND (Return)

13

SummarySummary

• 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

• 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

ConclusionConclusion

•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

•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