Driver for a power converter and a method of driving a switch thereof

1. A driver comprising switching circuitry referenced to a voltage level and configured to provide a drive signal for a switch referenced to another voltage level and subject to a control voltage limit, said switching circuitry including a first pair of series-coupled driver switches of opposite polarity with a common node therebetween coupled through a clamp driver switch to a second pair of series-coupled driver switches of opposite polarity, wherein said clamp driver switch is configured to limit a voltage to a control terminal of one of said second pair of series-coupled driver switches by a bias voltage applied to a control terminal of said clamp driver switch.

2. The driver as recited in claim 1 wherein said switching circuitry is referenced to a ground potential and said switch is referenced to about five volts.

3. The driver as recited in claim 1 wherein said switch is a metal oxide semiconductor field effect transistor (MOSFET) referenced to said another voltage, said switching circuitry configured to provide a gate drive signal for said switch within a gate voltage limit thereof.

4. The driver as recited in claim 1 wherein said second pair of series-coupled driver switches of opposite polarity are coupled through another clamp driver switch to said first pair of series-coupled driver switches of opposite polarity.

5. The driver as recited in claim 1 wherein said switching circuitry is configured to enable a mode of operation wherein said drive signal for said switch is referenced to said voltage level.

6. For use with a power converter couplable to a source of electrical power adapted to provide an input voltage thereto, said power converter including a power train having a switch referenced to said input voltage and subject to a control voltage limit, a driver, comprising:

switching circuitry referenced to a voltage level different from said input voltage and configured to provide a drive signal for said switch within said control voltage limit of said switch, said switching circuitry including a first pair of series-coupled driver switches of opposite polarity with a common node therebetween coupled through a clamp driver switch to a second pair of series-coupled driver switches of opposite polarity, wherein said clamp driver switch is configured to limit a voltage to a control terminal of one of said second pair of series-coupled driver switches by a bias voltage applied to a control terminal of said clamp driver switch.

7. The driver as recited in claim 6 wherein said input voltage is about five volts and said switching circuitry is referenced to a ground potential.

8. The driver as recited in claim 6 wherein said switch is a metal oxide semiconductor field effect transistor (MOSFET) referenced to said input voltage, said switching circuitry configured to provide a gate drive signal for said switch within a gate voltage limit thereof.

9. The driver as recited in claim 6 wherein said second pair of series-coupled driver switches of opposite polarity are coupled through another clamp driver switch to said first pair of series-coupled driver switches of opposite polarity.

10. The driver as recited in claim 6 wherein said switching circuitry is configured to enable a mode of operation wherein said drive signal for said switch is referenced to said voltage level.

11. For use with a power converter couplable to a source of electrical power adapted to provide an input voltage thereto, a method of driving a switch of said power converter referenced to said input voltage and subject to a control voltage limit, comprising:

providing a drive signal for said switch within said control voltage limit of said switch with switching circuitry referenced from a voltage level different from said input voltage, said switching circuitry including a first pair of series-coupled driver switches of opposite polarity with a common node therebetween coupled through a clamp driver switch to a second pair of series-coupled driver switches of opposite polarity, wherein said clamp driver switch is configured to limit a voltage to a control terminal of one of said second pair of series-coupled driver switches by a bias voltage applied to a control terminal of said clamp driver switch.

12. The method as recited in claim 11 wherein said input voltage is about five volts and said switching circuitry is referenced to a ground potential.

13. The method as recited in claim 11 wherein said switch is a metal oxide semiconductor field effect transistor (MOSFET) referenced to said input voltage, said switching circuitry providing a gate drive signal for said switch within a gate voltage limit thereof.

14. The method as recited in claim 11 wherein said second pair of series-coupled driver switches of opposite polarity are coupled through another clamp driver switch to said first pair of series-coupled driver switches of opposite polarity.

15. The method as recited in claim 11 further comprising enabling a mode of operation wherein said drive signal for said switch is referenced to said voltage level.

16. A power converter couplable to a source of electrical power adapted to provide an input voltage thereto, comprising:

a power train including a switch, referenced to said input voltage and subject to a control voltage limit, configured to conduct for a duty cycle and provide a regulated output characteristic at an output of said power converter;

a controller configured to provide a signal to control said duty cycle of said switch; and

a driver including switching circuitry referenced to a voltage level different from said input voltage and configured to provide a drive signal for said switch within said control voltage limit as a function of said signal from said controller, said switching circuitry including a first pair of series-coupled driver switches of opposite polarity with a common node therebetween coupled through a clamp driver switch to a second pair of series-coupled driver switches of opposite polarity, wherein said clamp driver switch is configured to limit a voltage to a control terminal of one of said second pair of series-coupled driver switches by a bias voltage applied to a control terminal of said clamp driver switch.

17. The power converter as recited in claim 16 wherein said controller is configured to provide a complement of said signal to control said duty cycle of said switch, said driver being configured to provide said drive signal for said switch within said control voltage limit as a function of said complement of said signal from said controller.

18. The power converter as recited in claim 16 wherein said switch is a metal oxide semiconductor field effect transistor (MOSFET) referenced to said input voltage, said switching circuitry configured to provide a gate drive signal for said switch within a gate voltage limit thereof.

19. The power converter as recited in claim 16 wherein said second pair of series-coupled driver switches of opposite polarity are coupled through another clamp driver switch to said first pair of series-coupled driver switches of opposite polarity.

20. The power converter as recited in claim 16 wherein said switching circuitry is configured to enable a mode of operation wherein said drive signal for said switch is referenced to said voltage level.