Self-boosting amplifier
The technology described in this document can be embodied in an apparatus that includes an amplifier that includes a first Zeta converter connected to a power supply and a load. The amplifier also includes a second Zeta converter connected to the power supply and the load. The second Zeta converter is driven by a complementary duty cycle relative to the first Zeta converter. The amplifier also includes a controller to provide an audio signal to the first Zeta converter and the second Zeta converter for delivery to the load.
1. An apparatus comprising:
an amplifier comprising:
a first Zeta converter connected to a power supply and a load;
a second Zeta converter connected to the power supply and the load, the second Zeta converter being driven by a complementary duty cycle relative to the first Zeta converter; and
a controller to provide an audio signal to the first Zeta converter and the second Zeta converter for delivery to the load, wherein the controller is connected to the load to receive a voltage feedback signal, and wherein the controller is connected to a component of at least one of the first Zeta converter and the second Zeta converter to receive a current feedback signal.
2. The apparatus of claim 1 , wherein the amplifier is a class-D amplifier.
3. The apparatus of claim 1 , wherein both the first Zeta converter and the second Zeta converter are fourth order converters.
4. The apparatus of claim 1 , wherein both the first Zeta converter and the second Zeta converter employ a Zero Voltage Transition (ZVT) switching technique.
5. The apparatus of claim 1 , wherein each of the first Zeta converter and the second Zeta converter include an inductor directly connected to ground and a switch directly connected to the power supply.
6. The apparatus of claim 1 , wherein each of the first Zeta converter and the second Zeta converter use integrated magnetics to couple inductors.
7. The apparatus of claim 1 , wherein the controller is configured to initiate moving one or more poles and zeros to positions external to an operating frequency range of the amplifier.
8. The apparatus of claim 1 , wherein the load is at least one speaker.
9. The apparatus of claim 1 , wherein the voltage feedback signal comprises a common-mode correction signal.
10. The apparatus of claim 9 , wherein the common-mode correction signal is input to a compensator with a supply voltage reference signal.
11. The apparatus of claim 9 , wherein the differential-mode correction signal is input to a compensator with the audio signal.
12. The apparatus of claim 1 , wherein the voltage feedback signal comprises a differential-mode correction signal.
13. The apparatus of claim 1 , wherein the current feedback signal is compensated with a loop filter before being summed into a modulator control input.
14. The apparatus of claim 13 , wherein the compensated current feedback signal is summed with a compensated audio signal.
15. The apparatus of claim 13 , wherein the compensated current feedback signal is summed with a compensated supply reference signal.
16. An amplifier comprising:
a power stage comprising:
a first Zeta converter connectable to a power supply and a load;
a second Zeta converter connectable to the power supply and the load, the second Zeta converter being driven by a complementary duty cycle relative to the first Zeta converter; and
a controller to provide an audio signal to the first Zeta converter and the second Zeta converter for delivery to the load,
wherein the controller is configured to initiate moving the one or more poles and zeros to positions external to an operating frequency range of the amplifier, and
wherein the controller is connected to the load to receive a voltage feedback signal, and wherein the controller is connected to a component of at least one of the first Zeta converter and the second Zeta converter to receive a current feedback signal.
17. The amplifier of claim 16 , wherein the amplifier is a class-D amplifier.
18. The amplifier of claim 16 , wherein both the first Zeta converter and the Zeta converter are fourth order converters.
19. The amplifier of claim 16 , wherein each of the first Zeta converter and the second Zeta converter include an inductor directly connected to ground and a switch directly connected to the power supply.
20. The amplifier of claim 16 , wherein each of the first Zeta converter stage and the Zeta converter stage use integrated magnetics to couple inductors.
21. The amplifier of claim 16 , wherein both the first Zeta converter and the second Zeta converter employ a Zero Voltage Transition (ZVT) switching technique.
22. The amplifier of claim 16 , wherein the load is at least one speaker.
23. An apparatus comprising:
an amplifier comprising:
a first Zeta converter connected to a power supply and a load;
a second Zeta converter connected to the power supply and the load, the second Zeta converter being driven by a complementary duty cycle relative to the first Zeta converter; and
a controller to provide an audio signal to the first Zeta converter and the second Zeta converter for delivery to the load, wherein the controller is connected to the load to receive a voltage feedback signal and a current feedback signal,
wherein the voltage feedback signal comprises a differential-mode correction signal.
24. The apparatus of claim 23 , wherein the amplifier is a class-D amplifier.
25. The apparatus of claim 23 , wherein both the first Zeta converter and the second Zeta converter employ a Zero Voltage Transition (ZVT) switching technique.
26. The apparatus of claim 23 , wherein the load comprises at least one speaker.
27. An apparatus comprising:
an amplifier comprising:
a first Zeta converter connected to a power supply and a load;
a second Zeta converter connected to the power supply and the load, the second Zeta converter being driven by a complementary duty cycle relative to the first Zeta converter; and
a controller to provide an audio signal to the first Zeta converter and the second Zeta converter for delivery to the load, wherein the controller is connected to the load to receive a voltage feedback signal and a current feedback signal,
wherein the current feedback signal is compensated with a loop filter before being summed into a modulator control input.
28. The apparatus of claim 27 , wherein the amplifier is a class-D amplifier.
29. The apparatus of claim 27 , wherein both the first Zeta converter and the second Zeta converter employ a Zero Voltage Transition (ZVT) switching technique.
30. The apparatus of claim 27 , wherein the load comprises at least one speaker.