Signal Integrity of a Multimedia Link

• US 20150255933A1
• Filed: 03/02/2015
• Published: 09/10/2015
• Est. Priority Date: 03/04/2014
• Status: Active Grant

• Current Assignee: Lattice Semiconductor Corporation
• Original Assignee: Silicon Image, Inc. (Lattice Semiconductor Corporation)
• Inventors: Sung, Baegin, Harrell, Chandlee B., Kim, Gyudong, Ranade, Shrikant
• Granted Patent: US 9,356,402 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01R 13/6471 by special arrangement of ground and signal conductors, e.g. GSGS [Ground-Signal-Ground-Signal]
• CPC Class Codes: H01R 13/6585 Shielding material individually surrounding or interposed between mutually spaced contacts

Abstract

In one embodiment, a source device and sink device communicate with one another via a multimedia link. The multimedia link includes a cable and a plug. The cable includes one or more data lines, power lines, ground lines or control bus lines. The plug includes a plurality of pins each connected to the one or more lines included in the cable. The plug also includes a ground plane and a power plane, wherein a ground pin of the plug connects the ground plane to the ground line of the cable of the multimedia link and a power pin of the plug connects the ground plane to the power line of the cable. In one example, the ground plane and power plane are placed within a threshold distance of one another, such that the power line connected to the power plane via the power pin behaves as a signal return path.

Claims

1. A multimedia link, comprising:

a plug, the plug comprising;

a ground pin;

a power pin;

a ground plane, the ground plane connected to a ground line of the multimedia link via the ground pin, the ground line configured as a signal return path;

a power plane, the power plane connected to a power line of the multimedia link via the power pin, the power line configured to a signal return path based on the distance between the ground plane and the power plane; and

a cable configured to encompass the power line and the ground line of the multimedia link.

2. The multimedia link of claim 1, wherein the power line configured as a signal return path based on the distance between the ground plane and the power plane comprises:

the power line configured as a signal return path when the distance between the ground plane and the power plane of the plug is less than a threshold distance.

3. The multimedia link of claim 2, wherein the power plane is AC coupled to the ground plane when the distance between the ground plane and the power plane of the plug is less than the threshold distance.

4. The multimedia link of claim 1, wherein the plug further comprises:

two differential pair pins; and

the ground pin positioned between the two differential pair pins.

5. The multimedia link of claim 1, wherein the plug further comprises:

two differential pair pins; and

the power pin positioned between the two differential pair pins.

6. The multimedia link of claim 1, wherein the plug further comprises:

a plurality of pins; and

a shield plane positioned behind the plurality of pins.

7. The multimedia link of claim 6, further comprising:

determining a first distance between the shield plane and each pin of the plurality of pins; and

controlling the characteristic impedance of each pin based on the first distance.

8. A device comprising a multimedia receptacle for interfacing with a multimedia link, the multimedia receptacle comprising:

a ground pin;

a power pin;

a ground plane, the ground plane connected to a ground line via the ground pin, the ground line configured as a signal return path; and

a power plane, the power plane connected to a power line via the power pin, the power line configured as a signal return path based on the distance between the ground plane and the power plane.

9. The multimedia receptacle of claim 8, wherein the power line configured as a signal return path based on the distance between the ground plane and the power plane comprises:

the power line configured as a signal return path when the distance between the ground plane and the power plane is less than a threshold distance.

10. The multimedia receptacle of claim 9, wherein the power plane is AC coupled to the ground plane when the distance between the ground plane and the power plane is less than the threshold distance.

11. The multimedia receptacle of claim 8, further comprising:

two differential pair pins; and

wherein, the ground pin is positioned between the two differential pair pins.

12. The multimedia receptacle of claim 8, further comprising:

two differential pair pins; and

wherein, the power pin is positioned between the two differential pair pins.

13. The multimedia receptacle of claim 8, further comprising:

an upper plane comprising a first plurality of pins;

a lower plane comprising a second plurality of pins; and

a shield plane positioned between the upper plane and the lower plane.

14. The multimedia receptacle of claim 13, further comprising:

determining a first distance between the shield plane and each pin of the plurality of pins; and

controlling the characteristic impedance of each pin based on the first distance.

15. The multimedia receptacle of claim 13, wherein the shield plane includes one or more shielding layers.

16. The multimedia receptacle of claim 13, further comprising:

a multimedia receptacle cable, configured to connect the first plurality of pins and the second plurality of pins to additional circuitry of the device via one or more lines; and

a multimedia shield line included within the multimedia receptacle cable positioned between the one or more lines of the multimedia receptacle cable and configured to control the impedance of the multimedia receptacle cable.

17. A non-transitory computer readable medium storing a representation of a multimedia link, the multimedia link comprising:

a plug, the plug comprising;

a ground pin;

a power pin;

a ground plane, the ground plane connected to a ground line of the multimedia link via the ground pin, the ground line configured as a signal return path;

a power plane, the power plane connected to a power line of the multimedia link via the power pin, the power line configured as a signal return path based on the distance between the ground plane and the power plane; and

a cable configured to encompass the power line and the ground line of the multimedia link.

18. The multimedia link of claim 17, wherein the power line configured as a signal return path based on the distance between the ground plane and the power plane comprises:

the power line configured as a signal return path when the distance between the ground plane and the power plane of the plug is less than a threshold distance, wherein the power plane is AC coupled to the ground plane when the distance between the ground plane and the power plane of the plug is less than the threshold distance.

19. The multimedia link of claim 17, wherein the plug further comprises:

two differential pair pins; and

the ground pin or the power pin is positioned between the two differential pair pins.

20. The multimedia link of claim 17, wherein the plug further comprises:

a plurality of pins; and

a shield plane positioned behind the plurality of pins;

wherein a distance between the shield plane and each pin of the plurality of pins controls the characteristic impedance of each pin.

21. A non-transitory computer readable medium storing a representation of a device comprising a multimedia receptacle for interfacing with a multimedia link, the multimedia receptacle comprising:

a ground pin;

a power pin;

a ground plane, the ground plane connected to a ground line via the ground pin, the ground line configured as a signal return path; and

a power plane, the power plane connected to a power line via the power pin, the power line configured as a signal return path based on the distance between the ground plane and the power plane.

22. The multimedia receptacle of claim 21, wherein the power line configured as a signal return path based on the distance between the ground plane and the power plane comprises:

the power line configured as a signal return path when the distance between the ground plane and the power plane is less than a threshold distance, wherein the power plane is AC coupled to the ground plane when the distance between the ground plane and the power plane is less than the threshold distance.

23. The multimedia receptacle of claim 21, further comprising:

two differential pair pins; and

wherein, the ground pin or the power pin is positioned between the two differential pair pins.

24. The multimedia receptacle of claim 21, further comprising:

an upper plane comprising a first plurality of pins;

a lower plane comprising a second plurality of pins; and

a shield plane located in between the upper plane and the lower plane.

25. The multimedia receptacle of claim 24, further comprising:

determining a first distance between the shield plane and each pin of the plurality of pins; and

controlling the characteristic impedance of each pin based on the first distance.

26. The multimedia receptacle of claim 21, wherein the shield plane includes one or more shielding layers.

27. The multimedia receptacle of claim 21, further comprising:

a multimedia receptacle cable, configured to connect the first plurality of pins and the second plurality of pins to additional circuitry of the device via one or more lines; and

a multimedia shield line included within the multimedia receptacle cable positioned between the one or more lines of the multimedia receptacle cable and configured to control the impedance of the multimedia receptacle cable.