Granted Patent B2

US 12,592,631 · App. 18/217,053 · Granted Mar 31, 2026

Inventors: Alex Dumais (Boise, ID); Andreas Reiter (Feldkirchen-Westerham, DE); Yong Yuenyongsgool (Gilbert, AZ); Stephen Bowling (Chandler, AZ); Timothy Phoenix (Pepperell, MA); Justin Oshea (Chandler, AZ)

Assignee: Microchip Technology Incorporated

H02M1/088H02M3/01H02M3/33571H02M1/0009

Abstract

Claims (62)

1 . An apparatus, comprising:

a current input interface to receive a current input indication, the current input indication to include a voltage to represent a current passing through of a primary side of an inductor-inductor-capacitor (LLC) power converter;

a voltage input interface to receive a voltage input, the voltage input to include a representative voltage to be provided from a secondary side of the LLC power converter; and

a control circuit to generate pulsed-width modulation (PWM) control signals for the LLC power converter, the PWM control signals to:

initiate an on-time period of a first leg of the LLC power converter;

truncate the on-time period of the first leg of the LLC power converter after a truncated on-time period, the truncated on-time period based on the current input indication and the voltage input;

initiate an on-time period of a second leg of the LLC power converter following a duration of time when the first leg and the second leg are off; and

match the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter, the on-time period of the second leg of the LLC power converter approximately equal to the truncated on-time period of the first leg of the LLC power converter.

2 . The apparatus of claim 1 , wherein the control circuit is to match the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter within a given single switching period of the LLC power converter.

3 . The apparatus of claim 1 , wherein the control circuit is to match the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter within a given single switching period of the LLC power converter for a plurality of consecutive switching periods of the LLC power converter.

4 . The apparatus of claim 1 , wherein the control circuit is to match the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter by determining the timing of the truncated on-time period of the first leg of the LLC power converter and applying the timing of the truncated on-time period of the first leg of the LLC power converter to the second leg of the LLC power converter.

5 . The apparatus of claim 1 , wherein the control circuit is to:

measure the voltage input;

compare the voltage input against a reference voltage to determine a voltage error;

use the voltage error to generate a reference current;

compare the reference current with the current input indication; and

wherein the PWM control signals to truncate the on-time period of the first leg of the LLC power converter when the current input indication is greater than or equal to the reference current.

6 . The apparatus of claim 1 , wherein the control circuit is to:

based on a determination that the current input indication is greater than or equal to a reference current, determine a first time since a beginning of a switching period of the LLC power converter until the determination that the current input indication is greater than or equal to the reference current; and

use the first time to set a second time, the second time to be used to set the on-time period of the second leg of the LLC power converter.

7 . The apparatus of claim 6 , wherein the first time is to include a designated dead-time for the first leg followed by the truncated on-time period of the first leg of the LLC power converter.

8 . The apparatus of claim 7 , wherein the control circuit is to set the on-time period of the second leg of the LLC power converter according to the truncated on-time period of the first leg of the LLC power converter.

9 . The apparatus of claim 6 , wherein the control circuit is to:

determine the truncated on-time period of the first leg of the LLC power converter from the first time; and

set the on-time period of the second leg of the LLC power converter to be the truncated on-time period of the first leg of the LLC power converter.

10 . The apparatus of claim 9 , wherein the control circuit is to set the second time to be a designated dead-time of the second leg of the LLC power converter followed by the truncated on-time period of the first leg of the LLC power converter.

11 . The apparatus of claim 1 , wherein the control circuit is to determine an automatic trigger for sampling the voltage input, wherein:

the automatic trigger is set according to an elapsed time from when a PWM signal is sent to the first leg of the LLC power converter to initiate the on-time period of the first leg of the LLC power converter until the current input indication is greater than or equal to a reference current plus an offset, wherein the offset is equal to a difference in time between when the current input indication is greater than or equal to the reference current and when a midpoint of the current input indication occurs in a given rise or fall period.

12 . A method, comprising:

receiving a current input indication, the current input indication to indicate a voltage to represent a current passing through of a primary side of an inductor-inductor-capacitor (LLC) power converter;

receiving a voltage input, the voltage input to include a representative voltage to be provided from a secondary side of the LLC power converter;

generating pulsed-width modulation (PWM) control signals for the LLC power converter to initiate an on-time period of a first leg of the LLC power converter;

generating PWM control signals to truncate the on-time period of the first leg of the LLC power converter after a truncated on-time period, the truncated on-time period based on the current input indication and the voltage input; and

generating PWM control signals to initiate an on-time period of a second leg of the LLC power converter following a duration of time when the first leg and the second leg are off;

generating PWM control signals to match the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter, the on-time period of the second leg of the LLC power converter approximately equal to the truncated on-time period of the first leg of the LLC power converter.

13 . The method of claim 12 , comprising matching the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter within a given single switching period of the LLC power converter.

14 . The method of claim 12 , comprising matching the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter within a given single switching period of the LLC power converter for a plurality of consecutive switching periods of the LLC power converter.

15 . The method of claim 12 , comprising matching the truncated on-time period of the first leg of the LLC power converter and the on-time period of the second leg of the LLC power converter by determining the timing of the truncated on-time period of the first leg of the LLC power converter and applying the timing of the truncated on-time period of the first leg of the LLC power converter to the second leg of the LLC power converter.

16 . The method of claim 12 , comprising:

measuring the voltage input;

comparing the voltage input against a reference voltage to determine a voltage error;

using the voltage error to determine a reference current;

comparing the reference current with the current input indication; and

wherein the generating PWM control signals to truncate the on-time period of the first leg of the LLC power converter comprises generating PWM control signals to truncate the on-time period of the first leg of the LLC power converter when the current input indication is greater than or equal to the reference current.

17 . The method of claim 12 , comprising:

based on a determination that the current input indication is greater than or equal to a reference current, determining a first time since a beginning of a switching period of the LLC power converter until the determination that the current input indication is greater than or equal to the reference current; and

using the first time to set a second time, the second time to be used to set the on-time period of the second leg of the LLC power converter.

18 . The method of claim 17 , wherein the first time is to include a designated dead-time for the first leg followed by the truncated on-time period of the first leg of the LLC power converter.

19 . The method of claim 18 , comprising setting the on-time period of the second leg of the LLC power converter according to the truncated on-time period of the first leg of the LLC power converter.

20 . An inductor-inductor-capacitor (LLC) power converter, comprising:

a first leg including a first switch;

a second leg including a second switch, the first switch connected between a voltage supply and a midpoint, and the second switch connected between the midpoint and ground;

a transformer including a primary side inductor and a secondary side inductor;

a low side inductor connected between the midpoint and the primary side inductor;

a capacitor connected between the primary side inductor and ground;

a current sensor in series with the capacitor, the primary side inductor and the current sensor to generate a current input indication;

a representative voltage received from the second side inductor;

a control circuit to:

receive the current input indication;

receive the representative voltage; and

based upon the current input indication and the representative voltage, generate pulsed-width modulation (PWM) control signals for the first leg and the second leg to:

initiate an on-time period of a first leg of the LLC power converter, truncate the on-time period of the first leg, initiate an on-time period of the second leg of the LLC power converter following a duration of time when the first leg and the second leg are off, and match the on-time period of the second leg and the truncated on-time period of the first leg, the on-time period of the second leg approximately equal to the truncated on-time period of the first leg.

Assignments (1)

Continuity (2)

References Cited (18)