Method and apparatus for regulating a voltage

• US 6,362,606 B1
• Filed: 09/12/2000
• Issued: 03/26/2002
• 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): Riley, Shawn
• Application Number:
  US09/659,876
• Time in Patent Office: 560 Days
• Field of Search: 323/272, 323/369, 323/271, 323/283
• US Class Current: 323/272
• CPC Class Codes: H03F 3/193 with field-effect devices H03F3/195 takes precedence

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 voltage regulator for providing a regulated voltage to a device residing on an integrated circuit, the voltage regulator comprising:

a first voltage regulator coupled between a voltage source and the power amplifier, the first voltage regulator residing on the integrated circuit;

a second voltage regulator coupled between the voltage source and the power amplifier, the second voltage regulator residing on the integrated circuit; and

an external resistor coupled between the second voltage regulator and the voltage source for dissipating power outside the integrated circuit.

2. The voltage regulator of claim 1, wherein the device is a power amplifier.

3. The voltage regulator of claim 1, further comprising control circuitry coupled to provide control signals to the first and second voltage regulators.

4. The voltage regulator of claim 3, wherein a control signal to the second voltage regulator controls whether power is dissipated through the external resistor.

5. The voltage regulator of claim 1, wherein the first and second voltage regulators each include a switching device.

6. The voltage regulator of claim 1, further comprising:

a third voltage regulator coupled between the voltage source and the power amplifier, the third voltage regulator residing on the integrated circuit; and

a second external resistor coupled between the third voltage regulator and the voltage source for dissipating power outside the integrated circuit.

7. The voltage regulator of claim 6, further comprising a plurality of control signals for controlling the first, second, and third voltage regulators.

22. The voltage regulator of claim 1, wherein the first and second voltage regulators are each comprised of a switching device and an op amp.

23. The voltage regulator of claim 22, wherein the switching devices of the first and second voltage regulators are controlled independently.

8. A voltage regulator for providing a regulated voltage to an integrated circuit on which the voltage regulator resides, the voltage regulator comprising:

a first regulator circuit coupled to a voltage source;

a second regulator circuit coupled to the voltage source; and

an external resistor coupled to the second regulator circuit for dissipating power outside the integrated circuit.

9. The voltage regulator of claim 8, further comprising control circuitry for controlling the amount of power dissipated through the external resistor.

10. The voltage regulator of claim 9, wherein the control circuitry selectively enables the first and second regulator circuits to control the amount of power dissipated through the external resistor.

11. The voltage regulator of claim 8, further comprising a third regulator circuit coupled to the voltage source, and further comprising a second external resistor coupled to the third regulator circuit for dissipating power outside the integrated circuit.

12. The voltage regulator of claim 8, further comprising a plurality of external resistors coupled to the regulator circuits for dissipating power outside the integrated circuit.

13. A method of providing a regulated a voltage from a voltage source comprising the steps of:

providing a first voltage regulator circuit coupled to the voltage source;

providing a second voltage regulator circuit coupled to the voltage source; and

connecting a resistance between the second voltage regulator circuit and the voltage source.

14. The method of claim 13, wherein the first and second voltage regulator circuits are provided on an integrated circuit, and wherein the resistance is external to the integrated circuit.

15. The method of claim 13, wherein each of the voltage regulator circuits includes a switching device.

16. The method of claim 15, further comprising the step of controlling the operation of the switching devices.

17. The method of claim 13, further comprising the step of providing control signals to the first and second regulator circuits.

18. The method of claim 17, wherein the control signals determine whether power is dissipated through the resistance.

19. The method of claim 13, further comprising the step of providing the regulated voltage to a device.

20. The method of claim 19, wherein the device is a power amplifier.

21. The method of claim 13, further comprising the steps of:

providing a third voltage regulator circuit coupled to the voltage source; and

connecting a second resistance between the third voltage regulator circuit and the voltage source.