Power saving techniques for a partial functionality communication link

• US 8,085,858 B2
• Filed: 08/05/2008
• Issued: 12/27/2011
• Est. Priority Date: 02/07/2007
• Status: Active Grant

• Current Assignee: Valens Semiconductor Ltd.
• Original Assignee: Valens Semiconductor Ltd.
• Inventors: Lida, Eyran, Avrahami, Avi, Benzaray, Alon, Banet, Nadav, Risling, Micha, Eyal, Massad, Brunin, Zeev
• Primary Examiner(s): Kim, Kevin
• Application Number:
  US12/185,838
• Publication Number:
  US 20080292007A1
• Time in Patent Office: 1,239 Days
• Field of Search: 375/257, 375/260, 375/299
• US Class Current: 375/257
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453

Abstract

Power saving techniques for a device including an active mode of operation for transmitting a first data stream of at least two data types over wires, and a low power partial functionality mode of operation for transmitting a second data stream over a subset of the wires used for transmitting the first data stream. The power saving techniques may utilize different modulation schemes, different throughputs, different symbol rates, or other techniques.

Claims

1. A device comprising:

an active mode of operation for transmitting a first data stream, comprising at least two data types, over a cable comprising conductive wires; and

at least one low power partial functionality mode of operation for transmitting a second data stream over at least a subset of the conductive wires used for transmitting the first data stream, wherein the low power partial functionality mode of operation utilizes a simpler modulation scheme than the modulation scheme utilized by the active mode of operation and the second data stream comprises less data types than the first data stream; and

wherein the throughput of the first data stream is at least 1.1 Gbps and the throughput of the second data stream is less than approximately 1/10 of the throughput of the first data stream.

2. The device of claim 1, wherein the cable is selected from the group of:

CAT5, CAT5e, CAT6, CAT6a, or CAT7.

3. The device of claim 2, wherein subset of the conductive wires utilized by the low power partial functionality mode of operation consists of one pair of the conductive wires for transmitting the second data stream and another pair of the conductive wires for receiving the second data stream.

4. The device of claim 1, wherein the low power partial functionality mode of operation utilizes a transmitting amplitude that is lower than the transmitting amplitude utilized by the active mode of operation.

5. The device of claim 1, further comprising the option of stopping to transmit in the low power partial functionality mode of operation when no valid data is available or expected to be available for transmission.

6. The device of claim 5, wherein a self clocking code is utilized in the low power partial functionality mode of operation.

7. A method comprising:

transmitting in a first mode of operation a first data stream, comprising at least two data types, over conductive wires using a first modulation scheme; and

transmitting in a second low power partial functionality mode of operation a second data stream, comprising less data types than the first data stream, over at least a subset of the conductive wires used for transmitting the first data stream, using a second modulation scheme that is simpler than the first modulation scheme.

8. The method of claim 7, wherein the conductive wires are a cable consisting of four pairs of conductive wires.

9. The method of claim 7, wherein the conductive wires are a cable selected from the group of:

CAT5, CAT5e, CAT6, CAT6a, or CAT7.

10. The method of claim 8, wherein the subset of the conductive wires consist of two pairs of the conductive wires, and further comprising transmitting the second data stream over a first pair of the conductive wires and receiving the second data stream over a second pair of the conductive wires.

11. The method of claim 8, further comprising transmitting the second data stream using a relatively lower amplitude than the amplitude used for transmitting the first data stream.

12. The method of claim 8, wherein the throughput of the first data stream is at least 1.1 Gbps and the throughput of the second data stream is less than approximately 1/10 of the throughput of the first data stream.

13. The method of claim 7, further comprising the option of stopping to transmit in the second low power partial functionality mode of operation when no valid data is available or expected to be available for transmission.

14. The method of claim 13, further comprising utilizing a self clocking code for transmitting the second data stream.

15. A method comprising:

transmitting in a first mode of operation, over a cable comprising conductive wires, a first asymmetric data stream comprising at least two data types; and

transmitting in a second low power partial functionality mode of operation, over a subset of the conductive wires used by the first mode of operation, a second bidirectional data stream;

wherein the ratio between the throughput of the first data stream and the throughput of the second data stream is at least approximately 10;

1, and wherein the first asymmetric data stream comprises at least one data type that is not included in the second bidirectional data stream.

16. The method of claim 15, wherein the cable consists of four pairs of conductive wires.

17. The method of claim 15, wherein the cable is selected from the group of:

CAT5, CAT5e, CAT6, CAT6a, or CAT7.

18. The method of claim 16, further comprising transmitting the second bidirectional data stream over a first pair of the conductive wires and receiving the second bidirectional data stream over a second pair of the conductive wires.

19. The method of claim 15, wherein the throughput of the first data stream is at least 1.1 Gbps and the throughput of the second data stream is less than approximately 1/10 of the throughput of the first data stream.

20. The method of claim 19, further comprising utilizing a simpler modulation scheme for transmitting the second bidirectional data stream than for transmitting the first asymmetric data stream.

21. The method of claim 19, further comprising transmitting the second bidirectional data stream using a lower amplitude than the amplitude used for transmitting the first asymmetric data stream.

22. The method of claim 15, further comprising the option of stopping to transmit in the second low power partial functionality mode of operation when no valid data is available or expected to be available for transmission.

23. The method of claim 22, further comprising utilizing a self clocking code for transmitting the second bidirectional data stream.

24. A method comprising:

transmitting in a first mode of operation bidirectional data between a source device and a sink device and unidirectional uncompressed high definition digital video from the source device to the sink device over at least a first subset of conductive wires comprised in a cable; and

transmitting in a second low power partial functionality mode of operation bidirectional data between the source device and the sink device over at least a second subset of the conductive wires used by the first mode of operation for transmitting the unidirectional uncompressed high definition digital video;

wherein the bidirectional data transmitted in the second low power partial functionality mode of operation comprises at least one data type that is also transmitted in the bidirectional data of the first mode of operation, and the transmissions in the second low power partial functionality mode of operation are at a much lower symbol rate compared to the transmissions of the first mode of operation.

25. The method of claim 24, wherein the cable comprises four pairs of the conductive wires and further comprising transmitting the unidirectional uncompressed high definition digital video over the four pairs of the conductive wires.

26. The method of claim 25, further comprising transmitting digital audio from the sink device to the source device in the second low power partial functionality mode of operation.

27. The method of claim 25, wherein the transmissions of the first and second modes of operation comprise data types defined by one or more of the following interfaces:

DVI, HDMI, or DisplayPort.

28. The method of claim 25, further comprising utilizing a simpler modulation scheme for transmitting in the second low power partial functionality mode of operation than for transmitting in the first mode of operation.

29. The method of claim 25, wherein the second subset of the conductive wires consists of two pairs of the conductive wires, and further comprising transmitting in the second low power partial functionality mode of operation over a first pair of the conductive wires and receiving over a second pair of the conductive wires.

30. The method of claim 25, further comprising transmitting the bidirectional data in the second low power partial functionality mode of operation using lower amplitude than the amplitude used for transmitting the bidirectional data in the first mode of operation.

31. The method of claim 24, wherein the cable comprises four pairs of the conductive wires and further comprising multiplexing the unidirectional uncompressed high definition digital video with audio.

32. The method of claim 24, further comprising transmitting in a third low power partial functionality mode of operation, over at least a third subset of the conductive wires used by the first mode of operation for transmitting the unidirectional uncompressed high definition digital video, at least one data type that is not transmitted in the second low power partial functionality mode of operation, and providing in the third low power partial functionality mode of operation at least one functionality that is not provided by the second low power partial functionality mode of operation.

33. The method of claim 24, further comprising the option of stopping to transmit in the second low power partial functionality mode of operation when no valid data is available or expected to be available for transmission.

34. The method of claim 33, further comprising utilizing a self clocking code for transmitting the bidirectional data in the second low power partial functionality mode of operation.