Push-pull driver with stage inversion and method of operation

• US 9,196,418 B2
• Filed: 10/24/2012
• Issued: 11/24/2015
• Est. Priority Date: 02/21/2012
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Tseng, Ryan
• Primary Examiner(s): Barnie, Rexford
• Assistant Examiner(s): WILLOUGHBY, TERRENCE RONIQUE
• Application Number:
  US13/659,657
• Publication Number:
  US 20130214610A1
• Time in Patent Office: 1,126 Days
• US Class Current: 1/1
• CPC Class Codes: H01F 38/14 Inductive couplings for wireless supply or distribution of electric power using inductive coupling H02J50/10
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H04B 5/24 Inductive coupling
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Systems, methods, and apparatus for amplifying a voltage in wireless power transmitters are disclosed. In one aspect, the transmitter comprises a first circuit configured to generate a first signal. The first signal comprises a non-inverted output. The transmitter further comprises a second circuit configured to generate a second signal in phase with the first signal. The second signal comprises an inverted output with respect to the non-inverted output. The first circuit and the second circuit are further configured to drive a load.

Claims

1. A transmitter for transferring power wirelessly, comprising:

a first circuit configured to output a first signal, the first signal comprising a non-inverted output, the first circuit comprising a first choke inductor; and

a second circuit configured to output a second signal in phase with the first signal, the second signal comprising an inverted output with respect to the non-inverted output such that the second signal is a mirror of the first signal, the second circuit comprising a second choke inductor inductively coupled to the first choke inductor, the first circuit and the second circuit further configured to drive a load.

2. The transmitter of claim 1, wherein the first circuit comprises a first driver and a first filter and the second circuit comprises a second driver and a second filter.

3. The transmitter of claim 2, wherein the first driver comprises a first switch and the first choke inductor and the second driver comprises a second switch and the second choke inductor.

4. The transmitter of claim 3, wherein the first choke inductor is coupled to a drain of the first switch, and wherein the second choke inductor is coupled to a source of the second switch.

5. The transmitter of claim 3, wherein the first choke inductor is coupled to a node of the first switch and a positive supply, and wherein the second choke inductor is coupled to a node of the second switch and a negative supply.

6. The transmitter of claim 5, wherein the first switch comprises a first transistor and the second switch comprises a second transistor, wherein the first choke inductor is coupled to a drain of the first transistor and the positive supply, and wherein the second choke inductor is coupled to a drain of the second transistor and the negative supply.

7. The transmitter of claim 2, wherein the first filter comprises a third inductor and the second filter comprises a fourth inductor, and wherein the third inductor is inductively coupled to the fourth inductor.

8. The transmitter of claim 7, wherein the first filter further comprises a fifth inductor and the second filter further comprises a sixth inductor, and wherein the fifth inductor is inductively coupled to the sixth inductor.

9. The transmitter of claim 1, wherein the first circuit is further configured to supply substantially half of a current to the load, and wherein the second circuit is further configured to supply substantially half of the current to the load.

10. The transmitter of claim 1, wherein the first circuit and the second circuit further are configured to drive a coil configured to generate a wireless field for wireless power transfer.

11. A method for amplifying a voltage, comprising:

outputting, by a first circuit, a first signal, the first signal comprising a non-inverted output, the first circuit comprising a first choke inductor;

outputting, by a second circuit, a second signal in phase with the first signal, the second signal comprising an inverted output with respect to the non-inverted output such that the second signal is a mirror of the first signal, the second circuit comprising a second choke inductor inductively coupled to the first choke inductor; and

driving a load based on the first signal and the second signal.

12. The method of claim 11, wherein the outputting the first signal further comprises:

coupling the first choke inductor to a ground during a first period of time; and

coupling the first choke inductor to a supply during a second period of time.

13. The method of claim 12, wherein the outputting the second signal further comprises:

coupling the second choke inductor to the supply during the first period of time; and

coupling the second choke inductor to the ground during the second period of time.

14. The method of claim 13, wherein the first choke inductor is of a same inductance as the second choke inductor.

15. The method of claim 11, further comprising filtering the first signal by a first filter and filtering the second signal by a second filter.

16. The method of claim 15, wherein filtering the first signal further comprises filtering the first signal based on a third inductor, and wherein filtering the second signal further comprises filtering the second signal based on a fourth inductor.

17. The method of claim 16, wherein the third inductor is inductively coupled to the fourth inductor.

18. The method of claim 11, wherein driving a load based on the first signal and the second signal comprises driving a coil configured to generate a wireless field for wireless power transfer based on the first signal and the second signal.

19. An apparatus configured to amplify a voltage, comprising:

means for outputting a first signal, the first signal comprising a non-inverted output, the means for outputting a first signal comprising a first choke inductor;

means for outputting a second signal in phase with the first signal, the second signal comprising an inverted output with respect to the non-inverted output such that the second signal is a mirror of the first signal, the means for outputting a second signal comprising a second choke inductor inductively coupled to the first choke inductor; and

means for driving a load based on the first signal and the second signal.

20. The apparatus of claim 19, wherein the means for outputting the first signal further comprises:

means for coupling the first choke inductor to a ground during a first period of time; and

means for coupling the first choke inductor to a supply during a second period of time.

21. The apparatus of claim 20, wherein the means for outputting the second signal further comprises:

means for coupling the second choke inductor to the supply during the first period of time; and

means for coupling the second choke inductor to the ground during the second period of time.

22. The apparatus of claim 21, wherein the first choke inductor is of a same inductance as the second choke inductor.

23. The apparatus of claim 19, further comprising means for filtering the first signal and means for filtering the second signal.

24. The apparatus of claim 23, wherein means for filtering the first signal further comprises means for filtering the first signal based on a third inductor, and wherein means for filtering the second signal further comprises means for filtering the second signal based on a fourth inductor.

25. The apparatus of claim 24, wherein the third inductor is inductively coupled to the fourth inductor.

26. The apparatus of claim 19, wherein the means for driving a load based on the first signal and the second signal comprises means for driving a coil configured to generate a wireless field for wireless power transfer based on the first signal and the second signal.

27. The apparatus of claim 19, wherein the means for outputting the first signal, the means for outputting the second signal, and the means for driving the load comprise a driver.

28. A non-transitory computer-readable medium comprising code that, when executed, causes an apparatus to:

output, by a first circuit, a first signal, the first signal comprising a non-inverted output, the first circuit comprising a first choke inductor;

output, by a second circuit, a second signal in phase with the first signal, the second signal comprising an inverted output with respect to the non-inverted output such that the second signal is a mirror of the first signal, the second circuit comprising a second choke inductor inductively coupled to the first choke inductor; and

drive a load based on the first signal and the second signal.

29. The medium of claim 28, further comprising code that, when executed, causes the apparatus to:

couple the first choke inductor to a ground during a first period of time; and

couple the first choke inductor to a supply during a second period of time.

30. The medium of claim 29, further comprising code that, when executed, causes the apparatus to:

couple the second choke inductor to the supply during the first period of time; and

couple the second choke inductor to the ground during the second period of time.

31. The medium of claim 30, wherein the first choke inductor is of a same inductance as the second choke inductor.

32. The medium of claim 28, further comprising code that, when executed, causes the apparatus to filter the first signal by a first filter and filter the second signal by a second filter.

33. The medium of claim 32, further comprising code that, when executed, causes the apparatus to filter the first signal based on a third inductor and filter the second signal based on a fourth inductor.

34. The medium of claim 33, wherein the third inductor is inductively coupled to the fourth inductor.

35. The medium of claim 28, further comprising code that, when executed, causes the apparatus to drive a coil configured to generate a wireless field for wireless power transfer based on the first signal and the second signal.