BUCK POWER STAGE WITH MULTIPLE MOSFET TYPES

• US 20160248329A1
• Filed: 02/23/2016
• Published: 08/25/2016
• Est. Priority Date: 02/23/2015
• Status: Active Grant

• Current Assignee: Empower Semiconductor
• Original Assignee: Empower Semiconductor
• Inventors: Phillips, Timothy Alan
• Granted Patent: US 9,843,258 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

A buck voltage converter is disclosed. The buck voltage generator includes a controller configured to generate one or more pulse width modulation (PWM) signals, and a plurality of serially connected switches configured to receive the PWM signals and to generate an output voltage signal at an output terminal based on the received PWM signals. The output voltage signal has an average voltage corresponding with a duty cycle of the PWM signals, a first switch of the plurality of serially connected switches has a first breakdown voltage and a second switch of the plurality of serially connected switches has a second breakdown voltage, and the first breakdown voltage is less than the second breakdown voltage.

Claims

1. A buck voltage converter, comprising:

a controller configured to generate one or more pulse width modulation (PWM) signals; and

a plurality of serially connected switches configured to receive the PWM signals and to generate an output voltage signal at an output terminal based on the received PWM signals, wherein the output voltage signal has an average voltage corresponding with a duty cycle of the PWM signals,

wherein a first switch of the plurality of serially connected switches has a first breakdown voltage and a second switch of the plurality of serially connected switches has a second breakdown voltage, and wherein the first breakdown voltage is less than the second breakdown voltage.

2. The buck voltage converter of claim 1, wherein the first switch is configured to receive a first of the one or more pulse PWM signals and to selectively conduct current according to the first PWM signal.

3. The buck voltage converter of claim 2, wherein the first switch is configured to receive an input voltage from an input voltage terminal and to provide current from the input voltage terminal to the output terminal through the second switch.

4. The buck voltage converter of claim 3, wherein a third switch of the plurality of serially connected switches is connected between the first and second switches, wherein the third switch has a third breakdown voltage, wherein the third breakdown voltage is substantially equal to the first breakdown voltage, and wherein the first switch is further configured to provide current from the input voltage terminal to the output terminal through the third switch.

5. The buck voltage converter of claim 4, wherein a fourth switch of the plurality of serially connected switches has a fourth breakdown voltage and a fifth switch of the plurality of serially connected switches has a fifth breakdown voltage, wherein the fourth switch is configured to receive a second of the one or more pulse PWM signals, wherein the fourth breakdown voltage is less than the fifth breakdown voltage, wherein a sixth switch of the plurality of serially connected switches is connected between the fourth and fifth switches, wherein the sixth switch has a sixth breakdown voltage, wherein the sixth breakdown voltage is substantially equal to the fourth breakdown voltage, and wherein the fourth switch is configured to source current to the output terminal through the fifth and sixth switches.

6. The buck voltage converter of claim 5, further comprising a semiconductor substrate, wherein the controller and the switches are integrated on the semiconductor substrate.

7. The buck voltage converter of claim 6, further comprising a filter configured to receive the output voltage signal from the switches and to generate an output voltage, wherein the output voltage is substantially DC and has a value substantially equal to the average voltage of the output voltage signal, and wherein the filter is integrated on the semiconductor substrate with the controller and the switches.

8. The buck voltage converter of claim 5, wherein the second switch is configured to receive a first bias voltage, the third switch is configured to receive a second bias voltage, the fifth switch is configured to receive a third bias voltage, and the sixth switch is configured to receive a fourth bias voltage, and wherein the first and third bias voltages are substantially equal.

9. The buck voltage converter of claim 8, wherein the first PWM signal is configured to switch between the voltage of the input voltage and the voltage of the second bias voltage, and wherein the second PWM signal is configured to switch between the voltage of the fourth bias voltage and a ground voltage.

10. The buck voltage converter of claim 5, wherein the second switch is configured to receive a first bias voltage, the third switch is configured to receive a second bias voltage, the fifth switch is configured to receive a third bias voltage, and the sixth switch is configured to receive a fourth bias voltage, and wherein the first and fourth bias voltages are substantially equal and the second and third bias voltages are substantially equal.

11. The buck voltage converter of claim 5, further comprising first and second inverters configured to respectively generate the first and second PWM signals, wherein the second switch is configured to receive a first bias voltage, the third switch is configured to receive a second bias voltage, the fifth switch is configured to receive a third bias voltage, and the sixth switch is configured to receive a fourth bias voltage, and wherein the first inverter has a ground connection connected to the second bias voltage and the second inverter has a power connection connected to the fourth bias voltage.

12. The buck voltage converter of claim 11, further comprising a bias voltage generator configured to generate the third bias voltage, wherein the bias voltage generator comprises a current path between the ground connection of the first inverter and the power connection of the second inverter.

13. The buck voltage converter of claim 11, further comprising a bias voltage generator configured to generate the third bias voltage, wherein third bias voltage is substantially equal to the input voltage minus the fourth bias voltage.

14. A buck voltage converter, comprising:

a plurality of serially connected switches configured to generate an output voltage signal at an output terminal, wherein the output voltage signal has an average voltage corresponding with a duty cycle of one or more PWM signals,

wherein a first switch of the plurality of serially connected switches has a first breakdown voltage and a second switch of the plurality of serially connected switches has a second breakdown voltage, and wherein the first breakdown voltage is less than the second breakdown voltage.

15. The buck voltage converter of claim 14, wherein the first switch is configured to receive a first of the one or more pulse PWM signals and to selectively conduct current according to the first PWM signal, wherein the first switch is configured to receive an input voltage from an input voltage terminal and to provide current from the input voltage terminal to the output terminal through the second switch, wherein a third switch of the plurality of serially connected switches is connected between the first and second switches, wherein the third switch has a third breakdown voltage, wherein the third breakdown voltage is substantially equal to the second breakdown voltage, wherein the first switch is further configured to provide current from the input voltage terminal to the output terminal through the third switch, wherein a fourth switch of the plurality of serially connected switches has a fourth breakdown voltage and a fifth switch of the plurality of serially connected switches has a fifth breakdown voltage, wherein the fourth switch is configured to receive a second of the one or more pulse PWM signals, wherein the fourth breakdown voltage is less than the fifth breakdown voltage, wherein a sixth switch of the plurality of serially connected switches is connected between the fourth and fifth switches, wherein the sixth switch has a sixth breakdown voltage, wherein the sixth breakdown voltage is substantially equal to the fourth breakdown voltage, and wherein the fourth switch is configured to sink current from the output terminal through the fifth and sixth switches.

16. The buck voltage converter of claim 15, further comprising a semiconductor substrate, wherein the controller and the switches are integrated on the semiconductor substrate.

17. The buck voltage converter of claim 16, further comprising a filter configured to receive the output voltage signal from the switches and to generate an output voltage, wherein the output voltage is substantially DC and has a value substantially equal to the average voltage of the output voltage signal, and wherein the filter is integrated on the semiconductor substrate with the controller and the switches.

18. The buck voltage converter of claim 15, wherein the second switch is configured to receive a first bias voltage, the third switch is configured to receive a second bias voltage, the fifth switch is configured to receive a third bias voltage, and the sixth switch is configured to receive a fourth bias voltage, and wherein the first and third bias voltages are substantially equal.

19. The buck voltage converter of claim 18, wherein the first PWM signal is configured to switch between the voltage of the input voltage and the voltage of the second bias voltage, and wherein the second PWM signal is configured to switch between the voltage of the fourth bias voltage and a ground voltage.

20. The buck voltage converter of claim 15, wherein the second switch is configured to receive a first bias voltage, the third switch is configured to receive a second bias voltage, the fifth switch is configured to receive a third bias voltage, and the sixth switch is configured to receive a fourth bias voltage, and wherein the first and fourth bias voltages are substantially equal and the second and third bias voltages are substantially equal.

21. The buck voltage converter of claim 15, further comprising first and second inverters configured to respectively generate the first and second PWM signals, wherein the second switch is configured to receive a first bias voltage, the third switch is configured to receive a second bias voltage, the fifth switch is configured to receive a third bias voltage, and the sixth switch is configured to receive a fourth bias voltage, and wherein the first inverter has a ground connection connected to the second bias voltage and the second inverter has a power connection connected to the fourth bias voltage.

22. The buck voltage converter of claim 21, further comprising a bias voltage generator configured to generate the third bias voltage, wherein the bias voltage generator comprises a current path between the ground connection of the first inverter and the power connection of the second inverter.

23. The buck voltage converter of claim 21, further comprising a bias voltage generator configured to generate the third bias voltage, wherein third bias voltage is substantially equal to the input voltage minus the fourth bias voltage.