Adaptive on-time generation for three-level power converters

Patent metadata

Field	Value
Publication number	US-11870345-B2
Application number	US-202117482287-A
Country	US
Kind code	B2
Filing date	Sep 22, 2021
Priority date	Sep 22, 2021
Publication date	Jan 9, 2024
Grant date	Jan 9, 2024

Abstract

A power converter circuit included in a computer system may include multiple devices and a switch node coupled to a regulated power supply node via an inductor. During a first time period, the power converter charges a capacitor, and the couples the capacitor to the switch node during a second time period. During a third time period the power converter couples the switch node to an input power supply node. To maintain constant charge delivered to the load during each time the switch node is coupled to the input power supply node, the duration of the third time period is adjusted based on a voltage level of the input power supply node, a voltage level of the regulated power supply node, a value of the inductor, and the durations of first and second time periods.

First claim

What is claimed is:

1. An apparatus, comprising:
a switch circuit including a plurality of devices, a capacitor, and a switch node coupled to a regulated power supply node via an inductor, wherein the switch circuit is configured to:
couple, during a first time period of a first cycle of a particular switching sequence, the capacitor between an input power supply node and the switch node using a first subset of the plurality of devices;
couple, during a second time period of the first cycle of the particular switching sequence, the capacitor between the switch node and a ground supply node using a second subset of the plurality of devices; and
couple, during a third time period of the first cycle of the particular switching sequence, the switch node to the input power supply node using a third subset of the plurality of devices; and

a control circuit configured to adjust a duration of the third time period based on a voltage level of the input power supply node, a voltage level of the regulated power supply node, a value of the inductor, and respective durations of first time period and the second time period.

2. The apparatus of claim 1 , wherein to adjust the duration of the third time period, the control circuit is further configured to:
perform a comparison of a ramp voltage to a threshold voltage; and
adjust, the duration of the third time period of the first cycle using results of the comparison.

3. The apparatus of claim 2 , wherein the control circuit is further configured to:
generate a tracking current using the voltage level of the input power supply node; and
generate the threshold voltage using the tracking current and a reference current.

4. The apparatus of claim 3 , wherein to generate the ramp voltage, the control circuit is further configured to:
generate a charge current using the voltage level of the input power supply node and the voltage level of the regulated power supply node; and
charge a capacitor using the charge current.

5. The apparatus of claim 2 , wherein the control circuit is further configured to generate the ramp voltage using the voltage level of the input power supply node and the voltage level of the regulated power supply node.

6. The apparatus of claim 1 , wherein the first time period and the second time period are fixed.

7. A method, comprising:
coupling, by a power converter circuit during a first portion of a first cycle of a particular switching sequence, an input power supply node to a switch node coupled to a regulated power supply node via an inductor;
coupling, by the power converter circuit during a second portion of the first cycle of the particular switching sequence, a capacitor between an input power supply node and the switch node;
coupling, by the power converter circuit during a third portion of the first cycle of the particular switching sequence, the switch node to ground supply node; and
adjusting, by the power converter circuit, a duration of the first portion of the first cycle of the particular switching sequence based on a voltage level of the input power supply node, a voltage level of the regulated power supply node, a value of the inductor, and respective durations of second and third portions of the first cycle.

8. The method of claim 7 , further comprising:
performing, by the power converter circuit, a comparison of the voltage level of the regulated power supply node and the voltage level of the input power supply node; and
selecting, by the power converter circuit, a different switching sequence using results of the comparison.

9. The method of claim 8 , further comprising:
coupling, by the power converter circuit during a first portion of a given cycle of the different switching sequence, the input power supply node to the switch node; and
adjusting, by the power converter circuit, a duration of the first portion of the given cycle of the different switching sequence using the voltage level of the input power supply node, the voltage level of the regulated power supply node, and the value of the inductor.

10. The method of claim 7 , wherein adjusting the duration of the first portion of the first cycle includes:
performing, by the power converter circuit, a comparison of a ramp voltage to a reference voltage; and
adjusting, by the power converter circuit, the duration of the first portion of the first cycle using results of the comparison.

11. The method of claim 10 , further comprising
generating, by the power converter circuit, a charging current whose value is based on the voltage level of the input power supply node and the voltage level of the regulated power supply node; and
charging, by the power converter circuit, a capacitor using the charging current to generate the ramp voltage.

12. The method of claim 10 , further comprising:
generating, by the power converter circuit, a tracking current using the voltage level of the input power supply node; and
combining, by the power converter circuit, a reference current and the tracking current to generate the reference voltage.

13. The method of claim 12 , wherein combining, the reference current and the tracking current includes subtracting, by the power converter circuit, the tracking current from the reference current.

14. An apparatus, comprising:
a load circuit coupled to a regulated power supply node; and
a power converter circuit that includes a switch node coupled to the regulated power supply node via an inductor, wherein the power converter circuit is configured to:
couple, during a first portion of a first cycle of a particular switching sequence, an input power supply node to the switch node;
couple, during a second portion of the first cycle of the particular switching sequence, a capacitor between an input power supply node and the switch node;
couple, during a third portion of the first cycle of the particular switching sequence, the switch node to ground supply node; and
adjust a duration of the first portion of the first cycle of the particular switching sequence based on a voltage level of the input power supply node, a voltage level of the regulated power supply node, a value of the inductor, and respective durations of second and third portions of the first cycle.

15. The apparatus of claim 14 , wherein the power converter circuit is further configured to:
perform a comparison of the voltage level of the regulated power supply node and the voltage level of the input power supply node; and
select a different switching sequence using results of the comparison.

16. The apparatus of claim 15 , wherein the power converter circuit is further configured to:
couple, during a first portion of a given cycle of the different switching sequence, the input power supply node to the switch node; and
adjust a duration of the first portion of the given cycle of the different switching sequence using the voltage level of the input power supply node, the voltage level of the regulated power supply node, and the value of the inductor.

17. The apparatus of claim 14 , wherein to adjust the duration of the first portion of the first cycle, the power converter circuit is further configured to:
perform a comparison of a ramp voltage to a reference voltage; and
adjust the duration of the first portion of the first cycle using results of the comparison.

18. The apparatus of claim 17 , wherein the power converter circuit is further configured to:
generate a charging current whose value is based on the voltage level of the input power supply node and the voltage level of the regulated

Assignees

• Apple Inc

Inventors

• Cai Chongli
• Du Dingkun
• Nussbaum Michael B

Classifications

• H02M3/158 Primary

  including plural semiconductor devices as final control devices for a single load · CPC title

• G06F1/28

  Supervision thereof, e.g. detecting power-supply failure by out of limits supervision · CPC title

• H02M3/157

  with digital control · CPC title

• H02M1/0003

  Details of control, feedback or regulation circuits · CPC title

• H02M1/0019

  the disturbance parameters being load current fluctuations · CPC title