System and Method for a Switching Converter

• US 20160036324A1
• Filed: 08/04/2014
• Published: 02/04/2016
• Est. Priority Date: 08/04/2014
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Hofmann, Andreas, Varga, Roberto
• Granted Patent: US 9,887,624 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H02M 1/14 Arrangements for reducing ripples from dc input or output
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H05B 45/3725 Switched mode power supply [SMPS]
• CPC Class Codes: H05B 45/375 using buck topology
• CPC Class Codes: H05B 45/38 using boost topology

Abstract

According to various embodiments, a method for operating a switching converter includes determining an operating parameter of the switching converter and, if the operating parameter is outside a first operating range, adjusting a control parameter in order to adjust the operating parameter to be within the first operating range. The operating parameter includes at least one of a switching frequency of the switching converter and a current ripple value of an output current.

Claims

1. A method for operating a switching converter, the method comprising:

determining an operating parameter of the switching converter, the operating parameter comprising at least one of a switching frequency of the switching converter and a current ripple value of an output current; and

if the operating parameter is outside a first operating range, adjusting a control parameter in order to adjust the operating parameter to be within the first operating range.

2. The method of claim 1, wherein the control parameter comprises at least one of a variable capacitance of the switching converter, a variable inductance of the switching converter, an on time period of the switching converter, an off time period of the switching converter, a maximum output current threshold, and a minimum output current threshold.

3. The method of claim 1, wherein:

the operating parameter comprises the switching frequency of the switching converter;

the first operating range comprises a first frequency range; and

adjusting the control parameter in order to adjust the operating parameter comprises adjusting the current ripple value of the output current in order to adjust the switching frequency to be within the first frequency range.

4. The method of claim 3, further comprising determining the current ripple value of the output current, wherein the current ripple value comprises a difference between a maximum value of the output current and a minimum value of the output current.

5. The method of claim 4, further comprising, if the current ripple value is outside a first current ripple range, adjusting the current ripple value to be within the first current ripple range.

6. The method of claim 3, wherein adjusting the current ripple value comprises adjusting at least one of a maximum output current threshold and a minimum output current threshold.

7. The method of claim 6, wherein adjusting the current ripple value further comprises adjusting a switching off time.

8. The method of claim 3, wherein the current ripple value and the switching frequency are inversely related.

9. The method of claim 3, further comprising operating as a buck converter to step an input voltage down to an output voltage.

10. A switching converter comprising:

a controller configured to;

determine a switching frequency of the switching converter; and

if the switching frequency is outside a first frequency range, adjust a current ripple value of an output current in order to adjust the switching frequency to be within the first frequency range.

11. The switching converter of claim 10, wherein the controller is further configured to determine the current ripple value of the output current, wherein the current ripple value comprises a difference between a maximum value of the output current and a minimum value of the output current.

12. The switching converter of claim 11, wherein the controller is further configured to, if the current ripple value is outside a first current ripple range, adjust the current ripple value to be within the first current ripple range.

13. The switching converter of claim 10, wherein adjusting the current ripple value comprises adjusting at least one of a maximum output current threshold and a minimum output current threshold.

14. The switching converter of claim 13, wherein adjusting the current ripple value further comprises adjusting a switching off time.

15. The switching converter of claim 10, wherein the current ripple value and the switching frequency are inversely related.

16. The switching converter of claim 10, wherein the switching converter comprises a buck converter.

17. The switching converter of claim 10, further comprising a load configured to receive the output current, wherein the load comprises a light emitting diode (LED).

18. The switching converter of claim 17, wherein the load comprises a plurality of LEDs.

19. A switching converter comprising:

a switching unit configured to be coupled to an energy storage element;

an average current controller coupled to the switching unit and configured to maintain an output current to the energy storage element having a substantially constant average value; and

a frequency ripple controller coupled to the switching unit and configured to;

determine a switching frequency of the switching converter,

determine a current ripple value of the output current from the switching converter, wherein the current ripple value comprises a difference between a maximum value of the output current and a minimum value of the output current, and

adjust the current ripple value and the switching frequency if either the current ripple value is outside of a first current ripple range or the switching frequency is outside a first frequency range.

20. The switching converter of claim 19, further comprising the energy storage element, wherein the energy storage element comprises an inductor configured to conduct the output current to a load.

21. The switching converter of claim 20, wherein the load comprises a plurality of light emitting diodes (LEDs).

22. The switching converter of claim 19, wherein adjusting the current ripple value and the switching frequency comprises adjusting at least one of a maximum output current threshold, a minimum output current threshold, an on time for the switching unit, and an off time for the switching unit.