Hybrid switched mode/linear power amplifier power supply for use in polar transmitter

• US 20050064830A1
• Filed: 09/16/2004
• Published: 03/24/2005
• Est. Priority Date: 09/16/2003
• Status: Active Grant

• Current Assignee: Nokia Technologies Oy (Nokia Corporation)
• Original Assignee: Nokia Corporation
• Inventors: Grigore, Vlad Gabriel
• Granted Patent: US 7,058,373 B2
• Time in Patent Office: Days
• US Class Current: 455/127.400
• CPC Class Codes: H03C 5/00 Amplitude modulation and angle modulation produced simultaneously or at will by the same modulating signal H03C7/00 takes precedence
• CPC Class Codes: H03F 1/0227 using supply converters
• CPC Class Codes: H03F 2200/451 the amplifier being a radio frequency amplifier
• CPC Class Codes: H03F 2200/504 the supply voltage or current being continuously controlled by a controlling signal, e.g. the controlling signal of a transistor implemented as variable resistor in a supply path for, an IC-block showed amplifier
• CPC Class Codes: H03F 3/217 Class D power amplifiers; Switching amplifiers
• CPC Class Codes: H03F 3/24 of transmitter output stages
• CPC Class Codes: H03F 3/68 Combinations of amplifiers, e.g. multi-channel amplifiers for stereophonics power amplifiers using a combination of several semiconductor amplifiers H03F3/211; combinations of amplifiers using coupling networks with distributed constants H03F3/602
• CPC Class Codes: H04B 1/0483 Transmitters with multiple parallel paths

Abstract

In one aspect this invention provides a DC-DC converter that has a switch mode part for coupling between a DC source and a load, the switch mode part providing x amount of output power; and that further has a linear mode part coupled in parallel with the switch mode part between the DC source and the load, the linear mode part providing y amount of output power, where x is preferably greater than y, and the ratio of x to y may be optimized for particular application constraints. In a further aspect there is a radio frequency (RF) transmitter (TX) for coupling to an antenna, where the TX has a polar architecture having an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA, where the power supply includes the switch mode part for coupling between a battery and the PA and the linear mode part coupled in parallel with the switch mode part between the battery and the PA.

Claims

1. A DC-DC converter, comprising:

a switch mode part for coupling between a DC source and a load, the switch mode part providing x amount of output power; and

a linear mode part coupled in parallel with the switch mode part between the same or a different DC source and the load, the linear mode part providing y amount of output power, where x is preferably greater than y, and the ratio of x to y may be optimized for particular application constraints,

where the linear mode part exhibits a faster response time to a required change in output voltage than the switch mode part.

2. A DC-DC converter as in claim 1, where the linear mode part comprises at least one power operational amplifier operating as a variable voltage source.

3. A DC-DC converter as in claim 1, where the linear mode part comprises at least one power operational transconductance amplifier operating as a variable current source.

4. A DC-DC converter as in claim 1, where the linear mode part provides only an AC component to the load.

5. A DC-DC converter as in claim 1, where the linear mode part provides a DC component and an AC component to the load.

6. A DC-DC converter as in claim 1, where the output of the linear mode part compensates for AC ripple output from the switch mode part.

7. A DC-DC converter as in claim 1, where the linear mode part comprises a bi-directional voltage controlled voltage source.

8. A DC-DC converter as in claim 1, where the linear mode part comprises a bi-directional voltage controlled voltage source (VCVS), and comprises two VCVS circuits, where in operation one operates as a sink and one as a source.

9. A DC-DC converter as in claim 1, where the linear mode part comprises a bi-directional voltage controlled current source.

10. A DC-DC converter as in claim 1, where the linear mode part comprises a bi-directional voltage controlled current source (VCCS), and comprises two VCCS circuits, where one operates as a sink and one as a source.

11. A DC-DC converter as in claim 1, where the switch mode part and the linear mode part are controlled in common by a control signal in a closed-loop manner.

12. A DC-DC converter as in claim 1, where the switch mode part is controlled by an output from the linear mode part in a closed-loop manner, and where the linear mode part is controlled by a control signal in a closed-loop manner.

13. A DC-DC converter as in claim 1, where the switch mode part is operated open-loop, and where the linear mode part is controlled by a control signal in a closed-loop manner.

14. A DC-DC converter as in claim 1, where the linear mode part is effectively slaved to operation of the switch mode part to source or sink current.

15. A DC-DC converter as in claim 1, where the switch mode part is provided with minimal or no output filter capacitance to function substantially as a current source.

16. A DC-DC converter as in claim 1, where the switch mode part is provided with an output filter capacitance and functions substantially as a voltage source.

17. A DC-DC converter as in claim 1, where the switch mode part is coupled to the load and to the output of the linear mode part through an inductance.

18. A DC-DC converter as in claim 1, where the load comprises at least one radio frequency power amplifier.

19. A DC-DC converter as in claim 11, where the load comprises at least one radio frequency (RF) power amplifier, and where the control signal comprises a RF carrier modulation signal.

20. A DC-DC converter as in claim 12, where the load comprises at least one radio frequency (RF) power amplifier, and where the control signal comprises a RF carrier modulation signal.

21. A DC-DC converter as in claim 13, where the load comprises at least one radio frequency (RF) power amplifier, and where the control signal comprises a RF carrier modulation signal.

22. A DC-DC converter as in claim 1, where the linear mode part is coupled to the output of the switch mode part and to the load through a capacitance.

23. A DC-DC converter as in claim 1, where the switch mode part is coupled to the load and to the output of the linear mode part through an inductance, and where the linear mode part is coupled to the output of the switch mode part, via the inductance, and to the load through a capacitance.

24. A DC-DC converter as in claim 1, where the linear mode part compensates at least in part for load variations.

25. A DC-DC converter as in claim 1, where the linear mode part compensates at least in part for non-ideal dynamics of the switch mode part.

26. A radio frequency (RF) transmitter (TX) for coupling to an antenna, said TX having a polar architecture comprised of an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA, where said power supply comprises a switch mode part for coupling between a power source and the PA, the switch mode part providing x amount of output power, said power supply further comprising a linear mode part coupled in parallel with the switch mode part between the power source and the PA, the linear mode part providing y amount of output power, where x is preferably greater than y, and the ratio of x to y may be optimized for particular application constraints, and where the linear mode part exhibits a faster response time to a required change in output voltage than the switch mode part.

27. A RF TX as in claim 26, where the linear mode part comprises at least one power operational amplifier operating as a variable voltage source.

28. A RF TX as in claim 26, where the linear mode part comprises at least one power operational transconductance amplifier operating as a variable current source.

29. A RF TX as in claim 26, where the linear mode part provides only an AC component to the PA.

30. A RF TX as in claim 26, where the linear mode part provides a DC component and an AC component to the PA.

31. A RF TX as in claim 26, where the output of the linear mode part compensates for AC ripple output from the switch mode part.

32. A RF TX as in claim 26, where the linear mode part comprises a bi-directional voltage controlled voltage source.

33. A RF TX as in claim 26, where the linear mode part comprises a bi-directional voltage controlled voltage source (VCVS), and comprises two VCVS circuits, where in operation one operates as a sink and one as a source.

34. A RF TX as in claim 26, where the linear mode part comprises a bi-directional voltage controlled current source.

35. A RF TX as in claim 26, where the linear mode part comprises a bi-directional voltage controlled current source (VCCS), and comprises two VCCS circuits, where one operates as a sink and one as a source.

36. A RF TX as in claim 26, where the switch mode part and the linear mode part are controlled in common by a control signal in a closed-loop manner, where the control signal comprises an AM signal.

37. A RF TX as in claim 26, where the switch mode part is controlled by an output from the linear mode part in a closed-loop manner, and where the linear mode part is controlled by a control signal in a closed-loop manner, where the control signal comprises an AM signal.

38. A RF TX as in claim 26, where the switch mode part is operated open-loop, and where the linear mode part is controlled by a control signal in a closed-loop manner, where the control signal comprises an AM signal.

39. A RF TX as in claim 26, where the linear mode part is effectively slaved to operation of the switch mode part to source or sink current.

40. A RF TX as in claim 26, where the switch mode part is provided with minimal or no output filter capacitance to function substantially as a current source.

41. A RF TX as in claim 26, where the switch mode part is provided with an output filter capacitance and functions substantially as a voltage source.

42. A RF TX as in claim 26, where the switch mode part is coupled to the PA and to the output of the linear mode part through an inductance.

43. A RF TX as in claim 26, where the switch mode part is coupled to the PA and to the output of the linear mode part through an inductance, and where the linear mode part is coupled to the output of the switch mode part, via the inductance, and to the PA through a capacitance.

44. A RF TX as in claim 26, where said power supply provides a greater power conversion efficiency than a purely linear voltage regulator-based power supply while also providing a wider operational bandwidth than a purely switch mode-based power supply.

45. A RF TX as in claim 26, where the linear mode part is coupled to the output of the switch mode part and to the load through a capacitance.

46. A RF TX as in claim 26, where the linear mode part compensates at least in part for variations in the load presented by the PA.

47. A RF TX as in claim 26, where the linear mode part compensates at least in part for non-ideal dynamics of the switch mode part.

48. A radio frequency (RF) transmitter (TX) for coupling to an antenna, said TX having a polar architecture comprised of an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA, where said power supply comprises a switch mode stage for coupling between a power source and the PA, the switch mode stage providing x amount of output power, said power supply further comprising at least one linear mode stage coupled in parallel with the switch mode stage between the power source and the PA, the linear mode stage providing y amount of output power, where x is preferably greater than y, and the ratio of x to y may be optimized for particular application constraints, further comprising at least one auxiliary inductance coupled between an output of the switch mode stage and an output of the at least one linear mode stage.

49. A RF TX as in claim 48, where the PA is coupled to the output of the switch mode stage before the auxiliary inductance, and further comprising at least one additional PA coupled to the output of the switch mode stage after the auxiliary inductance.

50. A RF TX as in claim 48, where the PA is coupled to the output of the switch mode stage after the auxiliary inductance, and further comprising at least one additional PA also coupled to the output of the switch mode stage after the auxiliary inductance.

51. A RF TX as in claim 48, where the PA is coupled to the output of the switch mode stage before a first auxiliary inductance and a second auxiliary inductance, and further comprising a second PA coupled to the output of the switch mode stage after the first auxiliary inductance, and a third PA coupled to the output of the switch mode stage after the second auxiliary inductance.

52. A RF TX as in claim 51, where the second PA is further coupled to the output of a first linear power stage, and the third PA is coupled to the output of a second linear power stage.

53. A RF TX as in claim 48, where the PA is coupled to the output of the switch mode stage after a first auxiliary inductance, and further comprising a second PA coupled to the output of the switch mode stage after a second auxiliary inductance, where the PA is further coupled to the output of a first linear power stage, and the second PA is coupled to the output of a second linear power stage.

54. A RF TX as in claim 48, where the at least one linear mode stage comprises at least one power operational amplifier operating as a variable voltage source.

55. A RF TX as in claim 48, where the at least one linear mode stage comprises at least one power operational transconductance amplifier operating as a variable current source.

56. A RF TX as in claim 48, where the at least one linear mode stage provides only an AC component to the PA.

57. A RF TX as in claim 48, where the at least one linear mode stage provides a DC component and an AC component to the PA.

58. A RF TX as in claim 48, where the output of the at least one linear mode stage compensates for AC ripple output from the switch mode stage.

59. A RF TX as in claim 48, where the switch mode stage and the at least one linear mode stage are controlled in common by a control signal in a closed-loop manner, where the control signal comprises an AM signal.

60. A RF TX as in claim 48, where the switch mode stage is controlled by an output from the at least one linear mode stage in a closed-loop manner, and where the at least one linear mode stage is controlled by a control signal in a closed-loop manner, where the control signal comprises an AM signal.

61. A RF TX as in claim 48, where the switch mode stage is operated open-loop, and where the at least one linear mode stage is controlled by a control signal in a closed-loop manner, where the control signal comprises an AM signal.

62. A RF TX as in claim 48, where the at least one linear mode stage is effectively slaved to operation of the switch mode stage to source or sink current.

63. A RF TX as in claim 48, where the switch mode stage is provided with an output filter capacitance and functions substantially as a voltage source, and provides a smoothed voltage signal to said auxiliary inductance.

64. A RF TX as in claim 48, where the at least one linear mode stage is coupled to the output of the switch mode stage and to the PA through a capacitance.

65. A RF TX as in claim 48, where the at least one linear mode stage compensates at least in part for variations in the load presented by the PA.

66. A RF TX as in claim 48, where the at least one linear mode stage compensates at least in part for non-ideal dynamics of the switch mode stage.

67. A RF TX as in claim 48, further comprising a switch coupled to a reference input of said switch mode stage for selectively applying different reference signals to said switch mode stage as a function of a mode of operation.

68. A RF TX as in claim 67, where one mode of operation comprises a GSM mode.

69. A RF TX as in claim 67, where one mode of operation comprises an EDGE mode.

70. A RF TX as in claim 67, where one mode of operation comprises a CDMA mode.

71. A RF TX as in claim 67, where one mode of operation comprises a WCDMA mode.

72. A RF TX as in claim 48, further comprising a switch coupled to a feedback input of said at least one linear mode stage for selectively applying different feedback signals to said at least one linear mode stage as a function of a mode of operation.

73. A RF TX as in claim 72, where one mode of operation comprises a GSM mode.

74. A RF TX as in claim 72, where one mode of operation comprises an EDGE mode.

75. A RF TX as in claim 72, where one mode of operation comprises a CDMA mode.

76. A RF TX as in claim 72, where one mode of operation comprises a WCDMA mode.

77. A method to operate a radio frequency (RF) transmitter (TX), where the TX has a polar architecture comprised of an amplitude modulation (AM) path coupled to a power supply of a power amplifier (PA) and a phase modulation (PM) path coupled to an input of the PA, comprising:

providing the power supply so as to comprise a switch mode part for coupling between a power source and the PA, the switch mode part providing x amount of output power; and

coupling a linear mode part in parallel with the switch mode part between the power source and the PA, the linear mode part providing y amount of output power, where x is preferably greater than y, and the ratio of x to y may be optimized for particular application constraints, and where the linear mode part exhibits a faster response time to a required change in output voltage than the switch mode part.

78. A method as in claim 77, where the linear mode part comprises at least one power operational amplifier operating as one of a variable voltage source or at least one power operational transconductance amplifier operating as a variable current source.

79. A method as in claim 77, where the linear mode part provides only an AC component to the PA.

80. A method as in claim 77, where the linear mode part provides a DC component and an AC component to the PA.

81. A method as in claim 77, further comprising operating the linear mode part to compensate for at least one of AC ripple output from the switch mode part, variation in the load presented by the PA, and non-ideal dynamics of the switch mode part.

82. A method as in claim 77, where the linear mode part comprises one of a bi-directional voltage controlled voltage source and a bi-directional voltage controlled current source.

83. A method as in claim 77, further comprising controlling in common the switch mode part and the linear mode part with a control signal in a closed-loop manner, where the control signal comprises an AM signal.

84. A method as in claim 77, further comprising controlling the switch mode part with an output from the linear mode part in a closed-loop manner, and controlling the linear mode part in a closed-loop manner with a control signal that comprises an AM signal.

85. A method as in claim 77, further comprising operating the switch mode part in an open-loop manner, and controlling the linear mode part in a closed-loop manner with a control signal that comprises an AM signal.

86. A method as in claim 77, further comprising operating the linear mode part so as to be effectively slaved to operation of the switch mode part to source or sink current.

87. A method as in claim 77, comprising operating the switch mode part to function substantially as a current source.

88. A method as in claim 77, comprising operating the switch mode part to function substantially as a voltage source.

89. A method as in claim 77, further comprising coupling the switch mode part to the PA and to the output of the linear mode part through an inductance.

90. A method as in claim 77, further comprising coupling the switch mode part to the PA and to the output of the linear mode part through an inductance, and where the linear mode part is coupled to the output of the switch mode part, via the inductance, and to the PA through a capacitance.

91. A method as in claim 77, further comprising coupling the linear mode part to the output of the switch mode part and to the PA through a capacitance.