Separation of ring detection functions across isolation barrier for minimum power

• US 6,922,469 B2
• Filed: 05/05/2003
• Issued: 07/26/2005
• Est. Priority Date: 04/22/1997
• Status: Expired due to Fees

• Current Assignee: Silicon Laboratories Incorporated
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Scott, Jeffrey W., Welland, David R., Hein, Jerrell P., Sooch, Navdeep S.
• Primary Examiner(s): Tran, Sinh
• Assistant Examiner(s): SINGH, RAMNANDAN P
• Application Number:
  US10/429,335
• Publication Number:
  US 20030194083A1
• Time in Patent Office: 813 Days
• Field of Search: 379/399.01, 379/413.04
• US Class Current: 379/399.01
• CPC Class Codes: H04L 25/0266 Arrangements for providing Galvanic isolation, e.g. by means of magnetic or capacitive coupling
• CPC Class Codes: H04L 25/06 Dc level restoring means; Bias distortion correction ; Decision circuits providing symbol by symbol detection
• CPC Class Codes: H04L 7/033 using the transitions of the received signal to control the phase of the synchronising-signal-generating means, e.g. using a phase-locked loop
• CPC Class Codes: H04M 1/573 Line monitoring circuits for detecting caller identification
• CPC Class Codes: H04M 11/06 Simultaneous speech and data transmission, e.g. telegraphic transmission over the same conductors
• CPC Class Codes: H04M 19/001 Current supply source at the exchanger providing current to substations
• CPC Class Codes: H04M 19/02 providing ringing current or supervisory tones, e.g. dialling tone or busy tone
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A communication system of the present invention utilizes ring detection circuitry on both sides of an isolation barrier. More particularly, the ring detection circuitry may include ring burst circuitry on the phone line side of the isolation barrier and ringer timing circuits on the powered side of the isolation barrier. The digital burst peak signal may be transmitted through the isolation banier to the finger timing circuits. By splitting the ring detection circuitry so that the ringer timing circuits are placed on the powered side of the isolation barriers, a significant reduction in the power usage on the phone line side of the barrier related to the ring detection function may occur. The outputs of the ringing timing circuits may be provided to circuits on either side of the isolation barrier. Thus, the ring detection function may be accomplished in a system utilizing an efficient bidirectional capacitive barrier while still minimizing power usage on the line side of the barrier.

Claims

1. A communication system, comprising:

phone line side circuitry capable of being coupled to a user end of phone lines, the phone line side circuitry being configured to provide an output signal for sending data to the phone lines;

powered side circuitry capable of being coupled to the phone line side circuitry through an isolation barrier that comprises a plurality of isolation elements, the powered side circuitry being configured to be isolated from the phone lines in order to satisfy phone line isolation regulatory standards;

phone line side integrated ringer circuitry within the phone line side circuitry; and

powered side integrated ringer circuitry within the powered side circuitry;

wherein the powered side circuitry is configured to communicate a first digital differential signal to at least two of the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor;

wherein the phone line side circuitry is configured to communicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals;

wherein the powered side circuitry is further configured to provide a clock signal to the phone line side circuitry through at least one of the plurality of isolation elements; and

wherein the powered side circuitry and the phone line side circuitry are further configured so that power is capable of being provided from the powered side circuitry to the phone line side circuitry while still maintaining the isolation required by the phone line isolation regulatory standards.

2. The communication system of claim 1, further comprising the isolation barrier coupled between the phone line side circuitry and the powered side circuitry.

3. The communication system of claim 1, wherein each of said plurality of isolation elements of said isolation barrier comprises a capacitor.

4. The communication system of claim 1, wherein a portion of said plurality of isolation elements of said isolation barrier each comprises a capacitor.

5. The communication system of claim 1, wherein the phone line side circuitry and the powered side circuitry are configured to communicate across the isolation barrier through digital signals.

6. The communication system of claim 5, the digital signals including at least a first digital ringer signal.

7. The communication system of claim 6, the phone line side circuitry and the powered side circuitry being capable of transmitting the digital signals bidirectionally across the isolation barrier, the digital signals including at least the first digital ringer signal for transmission in a first direction across the isolation barrier and at least a second digital ringer signal for transmission in a second direction across the isolation barrier.

8. The communication system of claim 7, further comprising the isolation barrier coupled between the phone line side circuitry and the powered side circuitry.

9. The communication system of claim 1, further comprising the isolation barrier coupled between the phone line side circuitry and the powered side circuitry, wherein the phone line side circuitry and the powered side circuitry are configured to communicate across the isolation barrier through digital signals.

10. The communication system of claim 1, the phone line side integrated ringer circuitry comprising ringer burst detection circuitry.

11. The communication system of claim 10, the ringer burst detection circuitry being powered at least in part by power transmitted across the isolation barrier.

12. The communication system of claim 1, the powered side integrated ringer circuitry comprising ringer timing circuitry.

13. The communication system of claim 12, the phone line side integrated ringer circuitry comprising ringer burst detection circuitry.

14. The communication system of claim 1, wherein said powered side circuitiy is further configured to provide a clock signal to the phone line side circuitry through an isolation element that is separate from the first isolation capacitor and the second isolation capacitor.

15. The communication system of claim 1, wherein the first digital differential signal includes both data information and control information.

16. A communication system, comprising:

phone line side circuitry capable of being coupled to a user end of phone lines, the phone line side circuitry being configured to provide an output signal for sending data to the phone lines;

powered side circuitry capable of being coupled to the phone line side circuitry through an isolation barrier that comprises a plurality of isolation elements, the powered side circuitry being configured to be isolated from the phone lines in order to satisfy phone line isolation regulatory standards;

phone line side integrated ringer circuitry within the phone line side circuitry; and

powered side integrated ringer circuitry within the powered side circuitry;

wherein the powered side circuitry is configured to communicate a first digital differential signal to at least two of the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor;

wherein the phone line side circuitry is configured to conununicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals;

wherein the powered side circuitry is further configured to provide a clock signal to the phone line side circuitry through at least one of the plurality of isolation elements, the clock signal being provided from the powered side circuitry to the phone line side circuitry through an isolation element that is separate from the first isolation capacitor and the second isolation capacitor;

wherein the powered side circuitry and the phone line side circuitry are further configured so that power is capable of being provided from the powered side circuitry to the phone line side circuitry to generate at least one power supply within the phone line side circuitry, while still maintaining the isolation required by the phone line isolation regulatory standards; and

wherein at least one of the first digital differential signal and the second digital differential signal includes both data and control information.

17. The communication system of claim 16, further comprising the isolation barrier coupled between the phone line side circuitry and the powered side circuitry.

18. The communication system of claim 16, wherein each of said plurality of isolation elements of said isolation barrier comprises a capacitor.

19. The communication system of claim 16, wherein a portion of said plurality of isolation elements of said isolation barrier each comprises a capacitor.

20. The communication system of claim 16, wherein the phone line side circuitry and the powered side circuitry are configured to communicate across the isolation barrier through digital signals.

21. The communication system of claim 20, the digital signals including at least a first digital ringer signal.

22. The communication system of claim 21, the phone line side circuitry and the powered side circuitry being capable of transmitting the digital signals bidirectionally across the isolation barrier, the digital signals including at least the first digital ringer signal for transmission in a first direction across the isolation barrier and at least a second digital ringer signal for transmission in a second direction across the isolation barrier.

23. The communication system of claim 22, further comprising the isolation barrier coupled between the phone line side circuitry and the powered side circuitry.

24. The communication system of claim 16, further comprising the isolation barrier coupled between the phone line side circuitry and the powered side circuitry, wherein the phone line side circuitry and the powered side circuitry are configured to communicate across the isolation barrier through digital signals.

25. The communication system of claim 16, the phone line side integrated ringer circuitry comprising ringer burst detection circuitry.

26. The communication system of claim 25, the ringer burst detection circuitry being powered at least in part by power transmitted across the isolation barrier.

27. The communication system of claim 16, the powered side integrated ringer circuitry comprising ringer timing circuitry.

28. The communication system of claim 27, the phone line side integrated ringer circuitry comprising ringer burst detection circuitry.

29. A communication system, comprising:

phone line side circuitry capable of being coupled to a user end of phone lines, the phone line side circuitry being configured to provide an output signal for sending data to the phone lines;

powered side circuitry, the powered side circuitry being configured to be isolated from the phone lines in order to satisfy phone line isolation regulatory standards;

an isolation barrier coupled between the phone line side circuitry and the powered side circuitry, the isolation barrier comprising a plurality of isolation elements and allowing the bidirectional communication of digital signals from the phone line side circuitry and the powered side circuitry;

phone line side integrated ringer circuitry within the phone line side circuitry; and

powered side integrated ringer circuitry within the powered side circuitry;

wherein the powered side circuitry is configured to communicate a first digital differential signal to at least two of the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor;

wherein the phone line side circuitry is configured to communicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals;

wherein the powered side circuitry is further configured to provide a clock signal to the phone line side circuitry through at least one of the plurality of isolation elements; and

wherein the powered side circuitry and the phone line side circuitry are further configured so that power is capable of being provided from the powered side circuitry to the phone line side circuitry while still maintaining the isolation required by the phone line isolation regulatory standards.

30. The communication system of claim 29, wherein the phone line side integrated ringer circuitry is powered at least in part by power extracted from signals transmitted across the isolation barrier.

31. The communication system of claim 29, the phone line side integrated ringer circuitry comprising ringer burst detection circuitry.

32. The communication system of claim 31, the digital signals including at least a signal indicative of a ringer burst transmitted from the phone line side circuitry to the powered side circuitry.

33. The communication system of claim 29, the powered side integrated ringer circuitry comprising ringer timing circuitry.

34. The communication system of claim 33, the digital signals including at least a ringer timing signal transmitted from the powered side circuitry to the phone line side circuitry.

35. The communication system of claim 29, wherein said powered side circuitry is further configured to provide a clock signal to the phone line side circuitry through an isolation element that is separate from the first isolation capacitor and the second isolation capacitor.

36. The communication system of claim 29, wherein the first digital differential signal includes both data information and control information.

37. The communication system of claim 29, wherein each of said plurality of isolation elements of said isolation barrier comprises a capacitor.

38. The communication system of claim 29, wherein a portion of said plurality of isolation elements of said isolation barrier each comprises a capacitor.

39. A communication system, comprising:

phone line side circuitry capable of being coupled to a user end of phone lines, the phone line side circuitry being configured to provide an output signal for sending data to the phone lines;

powered side circuitry, the powered side circuitry being configured to be isolated from the phone lines in order to satisfy phone line isolation regulatory standards;

an isolation barrier coupled between the phone line side circuitry and the powered side circuitry, the isolation barrier comprising a plurality of isolation elements and allowing the bidirectional communication of digital signals from the phone line side circuitry and the powered side circuitry;

phone line side integrated ringer circuitry within the phone line side circuitry; and

powered side integrated ringer circuitry within the powered side circuitry;

wherein the powered side circuitry is configured to communicate a first digital differential signal to at least two of the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor;

wherein the phone line side circuitry is configured to communicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals;

wherein the powered side circuitry is further configured to provide a clock signal to the phone line side circuitry though at least one of the plurality of isolation elements, the clock signal being provided from the powered side circuitry to the phone line side circuitry through an isolation element that is separate from the first isolation capacitor and the second isolation capacitor;

wherein the powered side circuitry and the phone line side circuitry are further configured so that power is capable of being provided from the powered side circuitry to the phone line side circuitry to generate at least one power supply within the phone line side circuitry, while still maintaining the isolation required by the phone line isolation regulatory standards; and

wherein at least one of the first digital differential signal and the second digital differential signal includes both data and control information.

40. The communication system of claim 39, wherein the phone line side integrated ringer circuitry is powered at least in part by power extracted from signals transmitted across the isolation barrier.

41. The communication system of claim 39, the phone line side integrated ringer circuitry comprising ringer burst detection circuitry.

42. The communication system of claim 41, the digital signals including at least a signal indicative of a ringer burst transmitted from the phone line side circuitry to the powered side circuitry.

43. The communication system of claim 39, the powered side integrated ringer circuitry comprising ringer timing circuitry.

44. The communication system of claim 43, the digital signals including at least a ringer timing signal transmitted from the powered side circuitry to the phone line side circuitry.

45. The communication system of claim 39, wherein each of said plurality of isolation elements of said isolation barrier comprises a capacitor.

46. The communication system of claim 39, wherein a portion of said plurality of isolation elements of said isolation barrier each comprises a capacitor.

47. A method of providing a communication system capable of being coupled to a user end of a phone line, comprising:

coupling an isolation barrier between a powered side circuitry and a phone line side circuitry, the isolation barrier comprising a plurality of isolation elements;

configuring the powered side circuitry to communicate a first digital differential signal to at least two the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor, wherein the powered side circuitry is configured to be isolated from the phone line in order to satisfy phone line isolation regulatory standards;

configuring the phone line side circuitry to communicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals, the phone line side circuitry further configured to provide an output signal for sending data to the phone line;

configuring the powered side circuitry to provide a clock signal to the phone line side circuitry through at least one of the plurality of isolation elements;

configuring the powered side circuitry and the phone line side circuitry so that power is capable of being provided from the powered side circuitry to the phone line side circuitry while still maintaining the isolation required by the phone line isolation regulatory standards; and

partitioning ringer circuitry between both the powered side circuitry and the phone line side circuitry such that first integrated ringer circuitry is located within the powered side circuitry and a second integrated ringer circuitry is located with the phone line side circuitry.

48. The method of claim 47, further comprising passing digital data bidirectionally across the isolation barrier.

49. The method of claim 48, further comprising transmitting digital ringer data bidirectionally across the isolation barrier.

50. The method of claim 48, further comprising powering at least one portion of the second integrated ringer circuitry with power transmitted across the isolation barrier.

51. The method of claim 47, further comprising transmitting digital ringer burst signals from the first integrated ringer circuitry to the powered side circuitry.

52. The method of claim 47, further comprising transmitting digital ringer timing signals from the second integrated ringer circuitry to the phone line side circuitry.

53. The method of claim 47, wherein the clock signal is provided from the powered side circuitry to the phone line side circuitry through an isolation clement that is separate from the first isolation capacitor and the second isolation capacitor.

54. The method of claim 47, wherein the first digital differential signal includes both data information and control information.

55. The method of claim 47, wherein each of said plurality of isolation elements of said isolation barrier comprises a capacitor.

56. The method of claim 47, wherein a portion of said plurality of isolation elements of said isolation barrier each comprises a capacitor.

57. A method of providing a communication system capable of being coupled to a user end of a phone line, comprising:

coupling an isolation barrier between powered side circuitry and phone line side circuitry;

the isolation barrier comprising a plurality of isolation elements; and

configuring the powered side circuitry to communicate a first digital differential signal to at least two of the isolation barrier elements, the at least two isolation barrier elements comprising at least a first isolation capacitor and a second isolation capacitor, wherein the powered side circuitry is configured to be isolated from the phone line in order to satisfy phone line isolation regulatory standards;

configuring the phone line side circuitry to communicate a second digital differential signal to the first isolation capacitor and the second isolation capacitor, wherein at least one of the first digital differential signal and the second digital differential signal includes both data and control information and wherein the first and second digital differential signals are communicated across the same first and second isolation capacitors so that the first and second isolation capacitors bidirectionally transfer the first and second digital differential signals, the phone line side circuitry further configured to provide an output signal for sending data to a phone line;

configuring the powered side circuitry to provide a clock signal to the phone line side circuitry through at least one of the plurality of isolation elements, wherein the clock signal is provided from the powered side circuitry to the phone line side circuitry through an isolation element that is separate from the first isolation capacitor and the second isolation capacitor; and

configuring the powered side circuitry and the phone line side circuitry so that power is capable of being provided from the powered side circuitry to the phone line side circuitry to generate at least one power supply within the phone line side circuitry, while still maintaining the isolation required by the phone line isolation regulatory standards; and

partitioning ringer circuitry between both the powered side circuitry and the phone line side circuitry such that first integrated ringer circuitry is located within the powered side circuitry and a second integrated ringer circuitry is located with the phone line side circuitry.

58. The method of claim 57, further comprising passing digital data bidirectionally across the isolation barrier.

59. The method of claim 58, further comprising transmitting digital ringer data bidirectionally across the isolation barrier.

60. The method of claim 58, further comprising powering at least one poition of the second integrated ringer circuitry with power transmitted across the isolation barrier.

61. The method of claim 57, further comprising transmitting digital ringer burst signals from the first integrated ringer circuitry to the powered side circuitry.

62. The method of claim 57, further comprising transmitting digital ringer timing signals from the second integrated ringer circuitry to the phone line side circuitry.

63. The method of claim 57, wherein each of said plurality of isolation elements of said isolation barrier comprises a capacitor.

64. The method of claim 57, wherein a portion of said plurality of isolation elements of said isolation barrier each comprises a capacitor.