Stepwise drivers for DC/DC converters

• US 20060033553A1
• Filed: 08/16/2004
• Published: 02/16/2006
• Est. Priority Date: 08/16/2004
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Schrom, Gerhard, Hazucha, Peter, Karnik, Tanay, De, Vivek, Moon, Sung T.
• Granted Patent: US 7,394,298 B2
• Time in Patent Office: Days
• US Class Current: 327/530
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H03K 4/023 by repetitive charge or discharge of a capacitor, analogue generators

Abstract

Stepwise drivers for DC/DC converters are described herein. In one embodiment, a stepwise driver is provided to charge or discharge a gate capacitance of a power switch of a DC/DC converter. In a particular embodiment, a stepwise driver example includes multiple switching elements to sequentially switch to charge a gate capacitance of a power switch of a DC/DC converter from a first voltage to a second voltage in multiple steps. Other methods and apparatuses are also described.

Claims

1. A driver circuit, comprising:

a plurality of switching elements to sequentially switch to charge a gate capacitance of a power switch of a DC/DC converter from a first voltage to a second voltage in a plurality of steps.

2. The driver circuit of claim 1, further comprising an input circuit to receive a plurality of control signals to cause the plurality of switching elements to switch respectively.

3. The driver circuit of claim 2, wherein each of the plurality of control signal is to control each of the plurality of switching elements independently.

4. The driver circuit of claim 1, wherein only one of the switching elements is turned on while a remainder of the switching elements is turned off during one of the plurality of steps.

5. The driver circuit of claim 1, wherein the gate capacitance of the power switch is charged in a plurality of steps within a single switching cycle of the DC/DC converter.

6. The driver circuit of claim 1, wherein the gate capacitance of the power switch is discharged in a plurality of steps within a single switching cycle of the DC/DC converter.

7. The driver circuit of claim 1, wherein after the gate capacitance of the power switch is charged to the second voltage, the plurality of switching elements is to sequentially switch to discharge the gate capacitance of the power switch from the second voltage to the first voltage.

8. The driver circuit of claim 7, wherein during discharging the gate capacitance of the power switch, the plurality of switching elements sequentially switches in a reversed order with respect to a switching order when charging the gate capacitance of the power switch.

9. The driver circuit of claim 2, further comprising a plurality of supply rails coupled to the plurality of switching elements respectively to provide a plurality of voltages including the first voltage, the second voltage, and at least one intermediate voltage between the first and second voltages, wherein the gate capacitance of the power switch is charged from the first voltage to the at least one intermediate voltage via a respective switching element before being charged to the second voltage.

10. The driver circuit of claim 9, wherein at least one intermediate supply rail that provides the at least one intermediate voltage comprises an AC coupling device to couple the respective intermediate supply rail to the first supply rail.

11. The driver circuit of claim 10, wherein the AC coupling device is to store energy when the gate capacitance of the power switch is discharged in a step corresponding to the respective intermediate voltage associated with the respective intermediate supply rail, and wherein the stored energy is used to charge the gate capacitance in corresponding charging step of a subsequent switching cycle of the DC/DC converter without drawing power from a power supply.

12. A DC/DC converter, comprising:

a power switch; and

a driver circuit coupled to the power switch, the driver circuit including a plurality of switching elements to sequentially switch to charge a gate capacitance of the power switch from a first voltage to a second voltage in a plurality of steps.

13. The DC/DC converter of claim 12, wherein the driver circuit further comprises an input circuit to receive a plurality of control signals to cause the plurality of switching elements to switch respectively.

14. The DC/DC converter of claim 13, wherein each of the plurality of control signals is to control each of the plurality of switching elements independently.

15. The DC/DC converter of claim 12, wherein only one of the switching elements is turned on while a remainder of the switching elements is turned off during one of the plurality of steps.

16. The DC/DC converter of claim 12, wherein the gate capacitance of the power switch is charged in a plurality of steps within a single switching cycle of the DC/DC converter.

17. The DC/DC converter of claim 12, wherein the gate capacitance of the power switch is discharged in a plurality of steps within a single switching cycle of the DC/DC converter.

18. The DC/DC converter of claim 12, wherein after the gate capacitance of the power switch is charged to the second voltage, the plurality of switching elements is to sequentially switch to discharge the gate capacitance of the power switch from the second voltage to the first voltage.

19. The DC/DC converter of claim 18, wherein during discharging the gate capacitance of the power switch, the plurality of switching elements sequentially switches in a reversed order with respect to a switching order when charging the gate capacitance of the power switch.

20. The DC/DC converter of claim 13, wherein the driver circuit further comprises a plurality of supply rails coupled to the plurality of switching elements respectively to provide a plurality of voltages including the first voltage, the second voltage, and at least one intermediate voltage between the first and second voltages, wherein the gate capacitance of the power switch is charged from the first voltage to the at least one intermediate voltage via a respective switching element before being charged to the second voltage.

21. The DC/DC converter of claim 20, wherein at least one intermediate supply rail that provides the at least one intermediate voltage comprises an AC coupling device to couple the respective intermediate supply rail to the first supply rail.

22. The DC/DC converter of claim 21, wherein the AC coupling device is to store energy when the gate capacitance of the power switch is discharged in a step corresponding to the respective intermediate voltage associated with the respective intermediate supply rail, and wherein the stored energy is used to charge the gate capacitance in corresponding charging step of a subsequent switching cycle of the DC/DC converter without drawing power from a power supply.

23. A data processing system, comprising:

a bus;

a processor coupled to the bus;

one or more devices coupled to the bus; and

a DC/DC converter to provide a supply voltage to at least one of the processor and the one or more devices, the DC/DC converter including

a power switch to switch to provide the DC supply voltage, and

a driver circuit coupled to the power switch, the driver circuit including a plurality of switching elements to sequentially switch to charge a gate capacitance of the power switch from a first voltage to a second voltage in a plurality of steps.

24. The data processing system of claim 23, wherein the driver circuit further comprises an input circuit to receive a plurality of control signals to cause the plurality of switching elements to switch respectively.

25. The data processing system of claim 23, wherein only one of the switching elements is turned on while a remainder of the switching elements is turned off during one of the plurality of steps.

26. The data processing system of claim 23, wherein after the gate capacitance of the power switch is charged to the second voltage, the plurality of switching elements is to sequentially switch to discharge the gate capacitance of the power switch from the second voltage to the first voltage.

27. The data processing system of claim 25, wherein during discharging the gate capacitance of the power switch, the plurality of switching elements sequentially switches in a reversed order with respect to a switching order when charging the gate capacitance of the power switch.

28. The data processing system of claim 24, wherein the driver circuit further comprises a plurality of supply rails coupled to the plurality of switching elements respectively to provide a plurality of voltages including the first voltage, the second voltage, and at least one intermediate voltage between the first and second voltages, wherein the gate capacitance of the power switch is charged from the first voltage to the at least one intermediate voltage via a respective switching element before being charged to the second voltage.

29. A method, comprising:

receiving a plurality of control signals; and

sequentially switching a plurality of switching elements to charge a gate capacitance of a power switch of a DC/DC converter in a plurality of steps within a single switching cycle of the DC/DC converter, in response to the plurality of control signals respectively.

30. The method of claim 29, further comprising providing a plurality of supply voltages including the first voltage, the second voltage, and at least one intermediate voltage between the first and second voltages, wherein the gate capacitance of the power switch is charged from the first voltage to the at least one intermediate voltage via a respective switching element before being charged to the second voltage.

31. The method of claim 29, wherein sequentially switching comprises turning on only one of the switching elements while a remainder of the switching elements remains turned off during one of the plurality of steps.

32. The method of claim 29, further comprising sequentially switching the plurality of switching elements in a reversed order to discharge the gate capacitance of the power switch from the second voltage to the first voltage, after the gate capacitance of the power switch has been charged to the second voltage.