ADAPTIVE SWITCHING FREQUENCY ADJUSTMENT FOR A POWER SUPPLY

• US 20140210441A1
• Filed: 04/30/2013
• Published: 07/31/2014
• Est. Priority Date: 01/29/2013
• Status: Active Grant

• Current Assignee: Semtech Corporation
• Original Assignee: Semtech Corporation
• Inventors: Granger, Steven M., Xing, Kun, Mao, Min
• Granted Patent: US 10,404,165 B2
• Time in Patent Office: Days
• US Class Current: 323/282
• CPC Class Codes: H02M 1/0022 the disturbance parameters being input voltage fluctuations
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators

Abstract

Described herein are systems and methods for providing a variable switching frequency for a power supply. The system includes a controller and a filter. The controller generates a switching frequency for a power supply. The switching frequency is modified as a function of an input voltage and an output voltage. The filter provides the output voltage to a load based at least in part on the switching frequency generated by the controller. In one example, the controller adaptively modifies the switching frequency as a function of the input voltage and the output voltage in order to maintain a peak to peak current for an inductor.

Claims

1. A system, comprising:

a controller to generate a switching frequency for a power supply, wherein the controller modifies the switching frequency as a function of an input voltage and an output voltage; and

a filter to provide the output voltage to a load based at least in part on the switching frequency generated by the controller.

2. The system of claim 1, wherein the controller is a DC-DC controller.

3. The system of claim 1, wherein the filter includes an inductor.

4. The system of claim 3, wherein the controller adaptively modifies the switching frequency as a function of the input voltage and the output voltage in order to maintain a peak to peak current for the inductor.

5. The system of claim 1, wherein the controller generates a pulse width modulation signal based on the switching frequency.

6. The system of claim 1, wherein the switching frequency is further modified as a function of a fixed voltage provided by a fixed power source.

7. The system of claim 1, wherein the power supply is a switching mode power supply.

8. A system, comprising:

a signal generator that includes an input node, an output node electrically coupled to a fixed power source, and a switching frequency adjustment node electrically coupled to an output voltage, wherein the signal generator controls a switching frequency of a power supply as a function of an input voltage and the output voltage; and

a filter that includes an inductor, wherein the filter generates the output voltage for a load based at least in part on the switching frequency.

9. The system of claim 8, wherein the signal generator controls the switching frequency as a function of the input voltage and the output voltage in order to maintain a peak to peak current level of the inductor.

10. The system of claim 8, wherein the power supply is a switching mode power supply.

11. The system of claim 8, wherein a pulse width modulation signal is generated based at least in part on the switching frequency.

12. The system of claim 8, wherein the switching frequency adjustment node is electrically coupled to a first resistor and a second resistor.

13. The system of claim 12, wherein the second resistor is electrically coupled to the output voltage.

14. The system of claim 13, wherein the first resistor is electrically coupled to ground.

15. A method, comprising:

receiving an input voltage and an output voltage; and

generating a switching frequency as a function of the input voltage and the output voltage.

16. The method of claim 15, further comprising modifying the switching frequency as a function of a new input voltage and a new output voltage.

17. The method of claim 15, further comprising sending a pulse width modulation signal with the switching frequency to a filter.

18. The method of claim 17, further comprising maintaining a constant peak to peak current for an inductor of the filter.

19. The method of claim 15, wherein the generating further includes generating the switching frequency as a function of a fixed voltage provided by a fixed power source.

20. The method of claim 19, wherein the receiving includes receiving the fixed voltage via an output voltage node and receiving the output voltage via a switching frequency adjustment node.