Granted Patent B2

US 12,334,821 · App. 18/047,053 · Granted Jun 17, 2025

Inventors: Gerard Villar Piqué (Eindhoven, NL); Shubham Ajaykumar Khandelwal (Helmond, NL); Ravichandra Karadi (Eindhoven, NL)

Assignee: NXP B.V.

H02M3/156H02M1/0025H02M3/158

Abstract

Claims (64)

1. A voltage converter, comprising:

a power stage configured to generate an output voltage (Vo) and an output current (Io) based on a switching frequency (fs);

a primary control loop configured to vary the switching frequency (fs) in response to an on-time value code (Ton_code); and

a secondary control loop configured to generate the Ton_code;

wherein the secondary control loop is configured to set a T_high threshold and a T_low threshold.

2. The voltage converter of claim 1 :

wherein increasing the Ton_code increases an energy output by the power stage and reduces the switching frequency (fs); and

wherein decreasing the Ton_code decreases an energy output by the power stage and increases the switching frequency (fs).

3. The voltage converter of claim 1 :

wherein the secondary control loop is configured to define a set of forbidden switching frequencies.

4. The voltage converter of claim 3 :

wherein the secondary control loop is configured to set the Ton_code and/or the iLpeak_code such that the switching frequency (fs) is outside of the set of forbidden switching frequencies.

5. The voltage converter of claim 3 :

wherein the set of forbidden switching frequencies includes an audio band or a designated noise band.

6. The voltage converter of claim 1 :

wherein the power stage includes a high-side switch, a low-side switch and a driver circuit; and

wherein the driver circuit is configured to control the switches at the switching frequency (fs).

7. The voltage converter of claim 1 :

wherein the power stage includes an output inductor;

wherein the inductor, the output voltage (Vo), and the output current (Io) are configured to be coupled to a load; and

wherein the peak output current (iLpeak) is a peak inductor current.

8. The voltage converter of claim 1 :

wherein the voltage converter is either a DCM (Discontinuous Conduction Mode) voltage converter or a DC-DC voltage converter.

9. The voltage converter of claim 1 :

wherein the secondary control loop is configured to determine a current on-time value (current_Ton) based on a switching frequency (fs) of the power stage.

10. The voltage converter of claim 9 :

wherein if a switching period (Tp=1/fs) is less than the T_low threshold or greater than the T_high threshold, the secondary control loop adjusts the Ton_code by a first amount until the Tp is between the T_low threshold and the T_high threshold.

11. The voltage converter of claim 9 :

wherein if a switching period (Tp=1/fs) is less than the T_low threshold, the secondary control loop adjusts the Ton_code by a first amount until Tp is between the T_low threshold and the T_high threshold;

wherein if the Tp is greater than the T_high threshold, the secondary control loop adjusts the Ton_code by a second amount until Tp is between the T_low threshold and the T_high threshold; and

wherein the first and second amounts are different.

12. The voltage converter of claim 9 :

wherein the secondary control loop is configured to set a T_max threshold and a T_min threshold; and

wherein the T_max threshold is greater than the T_high threshold, and the T_min threshold is less than the T_low threshold.

13. The voltage converter of claim 12 :

wherein if a switching period (Tp=1/fs) is less than the T_Low threshold but greater than the T_min threshold, the secondary control loop adjusts the Ton_code by a first amount until Tp is between the T_low threshold and the T_high threshold; and

wherein if the Tp is less than the T_min threshold, the secondary control loop adjusts the Ton_code by a second amount until Tp is between the T_low threshold and the T_min threshold;

wherein if Tp is greater than the T_high threshold but less than the T_max threshold, the secondary control loop adjusts the Ton_code by a third amount until Tp is between the T_low threshold and the T_high threshold; and

wherein if the Tp is greater than the T_max threshold, the secondary control loop adjusts the Ton_code by a fourth amount until Tp is between the T_max threshold and the T_high threshold;

wherein current_Ton keeps on being corrected by the fourth amount until Tp is greater than the T_low threshold and less than the T_high threshold; and

wherein the first amount is less than the second amount, and the third amount is less than the fourth amount.

14. The voltage converter of claim 12 :

wherein the secondary control loop is configured to generate a switching pulse having a minimum Ton value if the switching frequency (fs) is below a predetermined minimum switching frequency.

15. A voltage converter, comprising:

a power stage configured to generate an output voltage (Vo) and an output current (Io) based on a switching frequency (fs);

a primary control loop configured to vary the switching frequency (fs) in response to a peak output current code (iLpeak_code); and

a secondary control loop configured to generate the iLpeak_code;

wherein the secondary control loop is configured to determine a peak output current (iLpeak_current) based on a switching frequency (fs) of the power stage; and

wherein the secondary control loop is configured to define an T_high threshold and an T_low threshold.

16. The voltage converter of claim 15 :

wherein if a switching period (Tp=1/fs) is less than the T_low threshold or greater than the T_high threshold, the secondary control loop adjusts the iLpeak_code by a first amount until Tp is between the T_low threshold and the T_high threshold.

17. The voltage converter of claim 15 :

wherein if a switching period (Tp=1/fs) is less than the T_low threshold, the secondary control loop adjusts the iLpeak_code by a first amount until Tp is between the T low threshold and the T_high threshold;

wherein if Tp is greater than the T_high threshold, the secondary control loop adjusts the iLpeak_code by a second amount until Tp is between the T_low threshold and the T high threshold; and

wherein the first and second amounts are different.

18. The voltage converter of claim 15 :

wherein the secondary control loop is configured to set a T_max threshold and a T min threshold; and

wherein the T_max threshold is greater than the T_high threshold, and the T_min threshold is less than the T_low threshold.

19. The voltage converter of claim 18 :

wherein if a switching period (Tp=1/fs) is less than the T_Low threshold but greater than the T_min threshold, the secondary control loop adjusts the iLpeak_code by a first amount until Tp is between the T_low threshold and the T_high threshold; and

wherein if the Tp is less than the T_min threshold, the secondary control loop adjusts the iLpeak_code by a second amount until Tp is between the T_low threshold and the T high threshold;

wherein if Tp is greater than the T_high threshold but less than the T_max threshold, the secondary control loop adjusts the iLpeak_code by a third amount until Tp is between the T_low threshold and the T_high threshold; and

wherein if the Tp is greater than the T_max threshold, the secondary control loop adjusts the iLpeak_code by a fourth amount until Tp is between the T_low threshold and the T_high threshold; and

wherein the first amount is less than the second amount, and the third amount is less than the fourth amount.

Assignments (1)

Continuity (1)

References Cited (10)