Power amplifier circuitry having inductive networks
View Patent ↗A method and apparatus is provided for use in power amplifiers for reducing the peak voltage that transistors are subjected to. A power amplifier is provided with first and second switching devices and an inductor connected between the switching devices. The switching devices are driven such that the switching devices are turned on and off during the same time intervals. Differential RF power amplifiers are also provided with inductive networks coupled at various nodes of the power amplifiers.
1. A differential RF power amplifier comprising:
a first power amplifier, the first power amplifier having a first switching device coupled between a first supply voltage and a first node, and a second switching device coupled between a second node and a second supply voltage;
a second power amplifier, the second power amplifier having a third switching device coupled between a third supply voltage and a third node, and a fourth switching device coupled between a fourth node and a fourth supply voltage; and
an inductive network coupled to the first, second, third, and fourth nodes, wherein the inductive network includes a first inductor coupled between the first and second nodes such that current can flow between the first and second nodes through the first inductor and a second inductor coupled between the third and fourth nodes such that current can flow between the third and fourth nodes through the second inductor, wherein the first and second inductors each include one or more coils, and wherein the inductive network provides at least one inductor having one or more coils between any two of the first, second, third, and fourth nodes.
2. The differential RF power amplifier of claim 1 , further comprising an output network coupled to the first and second power amplifiers.
3. The differential RF power amplifier of claim 1 , wherein the first and third supply voltages supply the same voltages.
4. The differential RF power amplifier of claim 1 , wherein the first and third supply voltages supply different voltages.
5. The differential RF power amplifier of claim 1 , wherein the second and fourth supply voltages are ground reference voltages.
6. The differential RF power amplifier of claim 1 , wherein the inductive network provides an inductance between any two of the first, second, third, and fourth nodes.
7. The differential RF power amplifier of claim 1 , wherein the inductive network provides an inductance between the first and second nodes.
8. The differential RF power amplifier of claim 1 , wherein the inductive network provides first and second series coupled inductances coupled between the first and second nodes, and third and fourth series coupled inductances coupled between the third and fourth nodes.
9. The differential RF power amplifier of claim 8 , wherein the inductive network provides a fifth inductance coupled between a fifth node formed between the first and second inductances and a sixth node formed between the third and fourth inductances.
10. The differential RF power amplifier of claim 8 , wherein a short is provided between a fifth node formed between the first and second inductances and a sixth node formed between the third and fourth inductances.
11. The differential RF power amplifier of claim 1 , wherein the inductive network provides a first inductance coupled between the first and second nodes, a second inductance coupled between the third and fourth nodes, and a third inductance coupled between the second and fourth nodes.
12. The differential RF power amplifier of claim 1 , wherein the inductive network provides a first inductance coupled between the first and second nodes, a second inductance coupled between the third and fourth nodes, and a third inductance coupled between the first and third nodes.
13. The differential RF power amplifier of claim 1 , wherein the inductive network provides first and second series coupled inductances coupled between the first and fourth nodes, and third and fourth series coupled inductances coupled between the second and third nodes.
14. The differential RF power amplifier of claim 13 , wherein the inductive network further provides a fifth inductance coupled between a fifth node formed between the first and second inductances and a sixth node formed between the third and fourth inductances.
15. The differential RF power amplifier of claim 1 , wherein the inductive network provides a first inductance coupled between the first node and the second node.
16. The differential RF power amplifier of claim 1 , wherein the inductive network provides a first inductance coupled between the fourth node and the third node.
17. The differential RF power amplifier of claim 16 , wherein the first and fourth nodes are shorted together, and wherein the second and third nodes are shorted together.
18. The differential RF power amplifier of claim 1 , wherein the inductance between the first and second nodes is greater than zero, wherein the inductance between the first and third nodes is greater than zero, wherein the inductance between the first and fourth nodes is greater than or equal to zero, wherein the inductance between the second and third nodes is greater than or equal to zero, wherein the inductance between the second and fourth nodes is greater than zero, and wherein the inductance between the third and fourth nodes is greater than zero.
19. A method of amplifying RF signals comprising:
providing a first RF power amplifier, the first power amplifier having a first switching device coupled between a first supply voltage and a first node, and a second switching device coupled between a second node and a second supply voltage;
providing a second RF power amplifier, the second power amplifier having a third switching device coupled between a third supply voltage and a third node, and a fourth switching device coupled between a fourth node and a fourth supply voltage;
coupling the first and second power amplifiers differentially; and
coupling an inductive network to the first and second RF power amplifiers, wherein the inductive network includes a first inductor coupled between the first and second nodes such that current can flow between the first and second nodes through the first inductor and a second inductor coupled between the third and fourth nodes such that current can flow between the third and fourth nodes through the second inductor, wherein the first and second inductors each include one or more coils, and wherein the inductive network provides at least one inductor having one or more coils between any two of the first, second, third, and fourth nodes.
20. The method of claim 19 , wherein the inductive network is coupled to the first, second, third, and fourth nodes.
21. The method of claim 20 , wherein the inductive network provides an inductance between any two of the first, second, third, and fourth nodes.
22. The method of claim 21 , wherein the inductance between the first and second nodes is greater than zero, wherein the inductance between the first and third nodes is greater than zero, wherein the inductance between the first and fourth nodes is greater than or equal to zero, wherein the inductance between the second and third nodes is greater than or equal to zero, wherein the inductance between the second and fourth nodes is greater than zero, and wherein the inductance between the third and fourth nodes is greater than zero.
23. A differential RF power amplifier comprising:
a first power amplifier, the first power amplifier having a first switching device coupled between a first supply voltage and a first node, and a second switching device coupled between a second node and a second supply voltage;
a first inductor coupled between the first and second nodes, the first inductor having one or more coils;
a second power amplifier, the second power amplifier having a third switching device coupled between a third supply voltage and a third node, and a fourth switching device coupled between a fourth node and a fourth supply voltage;
a second inductor coupled between the third and fourth nodes, the first inductor having one or more coils; and
an output network having a first input coupled to the first node, a second input coupled to the second node, a third input coupled to the third node, and a fourth input coupled to the fourth node, wherein the first and second inductors and the output network provide at least one inductor having one or more coils between any two of the first, second, third, and fourth nodes.
24. The differential RF power amplifier of claim 23 , wherein the first and third supply voltages supply the same voltages.
25. The differential RF power amplifier of claim 23 , wherein the first and third supply voltages supply different voltages.
26. The differential RF power amplifier of claim 23 , wherein the second and fourth supply voltages are ground reference voltages.
27. The differential RF power amplifier of claim 23 , further comprising a third inductor coupled between the second and fourth nodes, the first inductor having one or more coils.