Power supply circuits for gate drivers

• US 9,525,411 B2
• Filed: 11/13/2014
• Issued: 12/20/2016
• Est. Priority Date: 11/13/2014
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Schnell, Ryan, Richardson, Kenneth G.
• Primary Examiner(s): TRAN, VINCENT HUY
• Application Number:
  US14/540,762
• Publication Number:
  US 20160142049A1
• Time in Patent Office: 768 Days
• Field of Search: 713/323
• US Class Current: 1/1
• CPC Class Codes: H02M 1/0006 Arrangements for supplying an adequate voltage to the control circuit of converters
• 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: H02M 1/088 for the simultaneous control of series or parallel connected semiconductor devices
• CPC Class Codes: H03K 17/687 the devices being field-effect transistors

Abstract

An embodiment of a power supply circuit to generate a supply voltage for a gate driver circuit can include an isolated power supply circuit to receive a first voltage in a first isolated system and provide power to a cyclic charging power supply circuit, the cyclic charging power supply circuit providing a supply voltage to the gate driver circuit in a second isolated system, the isolated power supply circuit providing the power to the cyclic charging power supply circuit while the gate driver circuit drives a transistor in an on state. The isolated power supply circuit can include a control circuit to regulate the power provided to maintain or increase the supply voltage while the gate driver circuit drives the transistor in an on state. The power supply circuit can also include the cyclic charging power supply circuit to receive a second voltage in the second isolated system and provide the supply voltage to the gate driver circuit. The cyclic charging power supply circuit can include one or more of a bootstrap power supply circuit or a charge pump power supply circuit.

Claims

1. A power supply circuit to generate a supply voltage for a gate driver circuit, the power supply circuit comprising:

an isolated power supply circuit to receive a first voltage in a first isolated system and provide power to a cyclic charging power supply circuit, the cyclic charging power supply circuit providing the supply voltage to a gate driver circuit in a second isolated system, the isolated power supply circuit providing the power to the cyclic charging power supply circuit while the gate driver circuit drives a transistor in an on state.

2. The power supply circuit of claim 1, wherein the isolated power supply circuit includes a control circuit to regulate the power provided by the isolated power supply circuit to maintain or increase the supply voltage provided by the cyclic charging power supply circuit while the gate driver circuit drives the transistor in the on state.

3. The power supply circuit of claim 2, wherein the control circuit regulates the provided power by limiting a current supplied to the cyclic charging power supply circuit to a current level below a predetermined level.

4. The power supply circuit of claim 2, wherein the control circuit regulates the provided power by limiting the supply voltage to a voltage at a predetermined voltage level below a peak supply voltage level provided by the cyclic charging power supply circuit.

5. The power supply circuit of claim 2, wherein the control circuit regulates the provided power by limiting the provided power to below a predetermined power level.

6. The power supply circuit of claim 2, wherein the control circuit regulates the provided power by limiting the provided power as a function of a temperature of the isolated power supply.

7. The power supply circuit of claim 2, wherein the control circuit regulates the provided power by selecting an impedance connecting the isolated power supply circuit to the cyclic charging power supply circuit.

8. The power supply circuit of claim 1, further comprising the cyclic charging power supply circuit to receive a second voltage in the second isolated system and provide the supply voltage to the gate driver circuit, the supply voltage being electrically floating relative to the second voltage while the gate driver circuit drives the transistor in the on state.

9. The power supply circuit of claim 1, wherein the cyclic charging power supply circuit is a bootstrap power supply circuit including a capacitor connected to a second voltage via at least a diode.

10. The power supply circuit of claim 9, wherein the isolated power supply circuit provides the power to initially charge the capacitor of the bootstrap power supply circuit upon startup or reset of the power supply circuit.

11. The power supply circuit of claim 10, wherein the isolated power supply circuit provides the power to initially charge the capacitor of the bootstrap power supply circuit while gate driver circuits are inactive.

12. A method of generating a supply voltage for a gate driver circuit, the method comprising:

receiving, by an isolated power supply circuit, a first voltage in a first isolated system; and

providing, by the isolated power supply circuit, power to a cyclic charging power supply circuit, the cyclic charging power supply circuit providing a supply voltage to a gate driver circuit in a second isolated system, the isolated power supply circuit providing the power to the cyclic charging power supply circuit while the gate driver circuit drives a transistor in an on state.

13. The method of claim 12, further comprising regulating, by a control circuit of the isolated power supply circuit, the power provided by the isolated power supply circuit to maintain or increase the supply voltage provided by the cyclic charging power supply circuit while the gate driver circuit drives the transistor in the on state.

14. The method of claim 13, wherein the control circuit regulates the provided power by limiting a current supplied to the cyclic charging power supply circuit to a current level below a predetermined level.

15. The method of claim 13, wherein the control circuit regulates the provided power by limiting a voltage provided by the isolated power supply circuit to a voltage at a predetermined voltage level below a peak supply voltage level provided by the cyclic charging power supply circuit.

16. The method of claim 13, wherein the control circuit regulates the provided power by limiting the provided power to below a predetermined power level.

17. The method of claim 13, wherein the control circuit regulates the provided power by limiting the provided power as a function of a temperature of the isolated power supply.

18. The method of claim 13, wherein the control circuit regulates the provided power by selecting an impedance connecting the isolated power supply circuit to the cyclic charging power supply circuit.

19. The method of claim 12, further comprising:

receiving, by the cyclic charging power supply circuit, a second voltage in the second isolated system; and

providing, by the cyclic charging power supply circuit, the supply voltage to the gate driver circuit, the supply voltage being electrically floating relative to the second voltage while the gate driver circuit drives the transistor in the on state.

20. The method of claim 19, wherein the cyclic charging power supply circuit includes a bootstrap power supply circuit having a capacitor connected to the second voltage via at least a diode.

21. A power supply circuit to generate a supply voltage for a gate driver circuit, the power supply circuit comprising:

means for providing power to a cyclic charging power supply circuit, the cyclic charging power supply circuit providing the supply voltage to a gate driver circuit in a second isolated system, the means for providing power providing the power as a function of a received first voltage in a first isolated system and while the gate driver circuit drives a transistor in an on state; and

means for regulating the provided power to maintain or increase the supply voltage provided by the cyclic charging power supply circuit while the gate driver circuit drives the transistor in the on state.

22. The power supply circuit of claim 21, further comprising the cyclic charging power supply circuit to receive a second voltage in the second isolated system and provide the supply voltage to the gate driver circuit, the supply voltage being electrically floating relative to the second voltage while the gate driver circuit drives the transistor in the on state.