RF power amplifier circuitry and method for amplifying signals

• US 6,462,620 B1
• Filed: 09/12/2000
• Issued: 10/08/2002
• Est. Priority Date: 09/12/2000
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Silicon Laboratories Incorporated
• Inventors: Paul, Susanne A., Dupuis, Timothy J.
• Primary Examiner(s): Pascal, Robert
• Assistant Examiner(s): NGUYEN, KHANH V
• Application Number:
  US09/660,009
• Time in Patent Office: 756 Days
• Field of Search: 330/264, 330/269, 330/302, 330/307, 330/273, 330/262, 330/271
• US Class Current: 330/264
• CPC Class Codes: H01L 2224/16225 the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 27/08 including only semiconductor components of a single kind
• CPC Class Codes: H01L 2924/15311 being a ball array, e.g. BGA
• CPC Class Codes: H03F 3/19 with semiconductor devices only

Abstract

An RF power amplifier is provided for use with wireless transmission systems such as cellular phones. An RF power amplifier includes direct drive amplifier circuitry operating in a push-pull scheme. The RF power amplifier includes a pair of switching devices driven by a pair of mutually coupled inductive devices. The inductive devices may be magnetically or capacitively coupled together. The RF power amplifier may be formed on a single integrated circuit and include an on-chip bypass capacitor. The RF power amplifier may utilize a voltage regulator for providing a regulated voltage source. The RF power amplifier may be provided using a dual oxide gate device resulting in an improved amplifier. The RF power amplifier may be packaged using flip chip technology and multi-layer ceramic chip carrier technology.

Claims

1. A direct drive RF power amplifier comprising:

an input stage; and

a push-pull amplifier coupled to the input stage, wherein the push-pull amplifier has first and second transistors driven by capacitively coupled first and second inductors; and

a capacitor that capacitively couples the first and second inductors.

2. The RF power amplifier of claim 1, wherein the input stage and the push-pull amplifier are formed on a single integrated circuit.

3. The RF power amplifier of claim 2, further comprising a bypass capacitor formed on the integrated circuit.

4. The RF power amplifier of claim 2, further comprising a voltage regulator formed on the integrated circuit.

5. The RF power amplifier of claim 4, wherein the voltage regulator further comprises a resistive element formed external to the integrated circuit to dissipate power off the integrated circuit.

6. The RF power amplifier of claim 2, wherein the integrated circuit is a dual gate oxide circuit.

7. The RF power amplifier of claim 6, wherein the input stage includes at least one device having a first gate oxide thickness and the push-pull amplifier includes at least one device having a second gate oxide thickness, and wherein the first and second gate oxide thicknesses are different.

8. The RF power amplifier of claim 7, wherein the first gate oxide thickness is less than the second gate oxide thickness.

9. The RF power amplifier of claim 8, wherein the first gate oxide thickness is approximately 70 Å

and the second gate oxide thickness is approximately 140 Å

.

10. The RF power amplifier of claim 1, wherein the input stage and the push-pull amplifier are connected together without the use of a transformer.

11. The RF power amplifier of claim 1, wherein the input stage and the push-pull amplifier are connected together in a direct drive configuration.

12. The RF power amplifier of claim 1, further comprising a voltage regulator coupled to the push-pull amplifier for providing a regulated voltage.

13. The RF power amplifier of claim 1, wherein the RF power amplifier is packaged in a flip chip package.

14. The RF power amplifier of claim 1, wherein the RF power amplifier is using a flip chip package and a ceramic chip carrier.

15. An RF power amplifier for providing an amplified RF signal to an output node comprising:

a first switching device connected between a first power supply node and the output node;

a second switching device connected between a second power supply node and the output node;

a first reactive circuit connected between the first power supply node and a gate of the first switching device;

a second reactive circuit connected between the second power supply node and a gate of the second switching device; and

a third switching device connected between the second power supply node and the gate of the first switching device, said third switching device having a gate coupled to an RF input signal.

16. The RF power amplifier of claim 15, wherein the first reactive circuit is comprised of a first inductor and wherein the second reactive circuit is comprised of a second inductor.

17. The RF power amplifier of claim 16, wherein the first and second inductors are magnetically coupled.

18. The RF power amplifier of claim 16, wherein the RF power amplifier is flip chip bonded to a ceramic chip carrier and wherein said first and second inductors are built within the ceramic chip carrier.

19. The RF power amplifier of claim 15, wherein the third switching device has a first gate oxide thickness and the first and second switching devices have a second gate oxide thickness, and wherein the first and second gate oxide thicknesses are different.

20. The RF power amplifier of claim 15, further comprising a third reactive circuit connected between the gate of the first switching device and the gate of the second switching device.

21. The RF power amplifier of claim 20, wherein said third reactive circuit is comprised of a capacitor.

22. The RF power amplifier of claim 15, wherein the RF power amplifier is formed on an integrated circuit.

23. The RF power amplifier of claim 22, further comprising a voltage regulator formed on the integrated circuit.

24. The RF power amplifier of claim 23, wherein the voltage regulator further comprises a resistive element formed external to the integrated circuit to dissipate power off the integrated circuit.

25. The RF power amplifier of claim 15, further comprising a bypass capacitor connected between the first power supply node and the second power supply node.

26. The RF power amplifier of claim 15, wherein the first switching device is comprised of an n-channel transistor and the second switching device is comprised of an p-channel transistor.

27. The RF power amplifier of claim 15, wherein a reactive transformation network is connected between said output node and a load.

28. The RF power amplifier of claim 27, wherein the RF power amplifier is flip chip bonded to a ceramic chip carrier and wherein one or more components of the reactive transformation network are built within the ceramic chip carrier.

29. A method of amplifying RF signals comprising the steps of:

providing a first switching device connected between an output node and a voltage source;

providing a second switching device connected between the output node and ground;

connecting a first inductor between the voltage sourced and a gate of the first switching device;

connecting a second inductor between ground and a gate of the second switching device;

providing a third switching device connected between ground and the gate of the second switching device.

30. An RF power amplifier for providing an amplified RF signal to an output node comprising:

a first switching device having a gate and first and second outputs, wherein the first output of the first switching device is connected to an output node;

a second switching device having a gate and first and second outputs, wherein the first output of the second switching device is connected to the output node;

a first inductor connected between the gate and the second output of the first switching device for driving the first switching device;

a second inductor connected between the gate and the second output of the second switching device for driving the second switching device; and

a third switching device connected between ground and the gate of the first switching device, wherein the third switching device has a gate coupled to an RF input signal.

31. The RF power amplifier of claim 30, wherein the second output of the first switching device is connected to a voltage source and the second output of the second switching device is connected to ground.

32. The RF power amplifier of claim 30, wherein the RF power amplifier is formed on an integrated circuit.

33. The RF power amplifier of claim 32, wherein the RF power amplifier is flip chip bonded to a ceramic chip carrier and wherein said first and second inductors are built within the ceramic chip carrier.

34. The RF power amplifier of claim 30, wherein the third switching device has a first gate oxide thickness and the first and second switching devices have a second gate oxide thickness, and wherein the first and second gate oxide thicknesses are different.

35. The RF power amplifier of claim 30, further comprising a capacitor connected between the gate of the first switching device and the gate of the second switching device.

36. The RF power amplifier of claim 32, further comprising a voltage regulator formed on the integrated circuit.

37. The RF power amplifier of claim 36, wherein the voltage regulator further comprises a resistive element formed external to the integrated circuit to dissipate power off the integrated circuit.