Increasing the light-load efficiency of voltage regulators using nonlinear inductors with cores of different materials

Patent metadata

Field	Value
Publication number	US-9281116-B2
Application number	US-201213650046-A
Country	US
Kind code	B2
Filing date	Oct 11, 2012
Priority date	Oct 11, 2012
Publication date	Mar 8, 2016
Grant date	Mar 8, 2016

Abstract

The disclosed embodiments relate to a power supply for a portable electronic device. The power supply includes a power source and a nonlinear inductor. The nonlinear inductor includes a first core and a second core connected in series to the first core, wherein the second core has a higher permeability than the first core.

First claim

What is claimed is:

1. A power supply, comprising:
a power source;
a nonlinear inductor with an input terminal and an output terminal, comprising:
a first core; and
a second core connected in series to the first core, wherein the second core has a higher permeability than the first core;

an input switch comprising a control field-effect transistor (FET) configured to couple the input terminal to the power source;
a synchronous FET configured to couple the input terminal to a reference voltage;
an output path comprising a capacitor configured to produce an output voltage and coupled between the output voltage and the reference voltage; and
a control circuit configured to control the input switch to generate the output voltage.

2. The power supply of claim 1 , wherein the second core lacks an air gap.

3. The power supply of claim 1 , wherein the power supply is operated using at least one of:
a continuous conduction mode (CCM); and
a discontinuous conduction mode (DCM).

4. The power supply of claim 1 , wherein the second core is smaller than the first core.

5. The power supply of claim 1 , wherein a material of the first core is at least one of:
powdered iron; and
sand dust.

6. The power supply of claim 1 , wherein a material of the second core is at least one of:
ferrite;
nickel zinc; and
nickel manganese.

7. A method for supplying power to components, comprising:
providing a nonlinear inductor comprising an input terminal, an output terminal, a first core, and a second core connected in series to the first core, wherein the second core has a higher permeability than the first core; and
using the nonlinear inductor to transfer power from a power source to the electronic components,
wherein an input switch comprising a control field-effect transistor (FET) couples the input terminal to the power source,
wherein a synchronous FET couples the input terminal to a reference voltage,
wherein an output path of the nonlinear inductor produces an output voltage and comprises a capacitor coupled between the output voltage and the reference voltage, and
wherein a control circuit controls the input switch to generate the output voltage.

8. The method of claim 7 , wherein the power is transferred from the power source to the components using at least one of:
a continuous conduction mode (CCM); and
a discontinuous conduction mode (DCM).

9. The method of claim 7 , wherein the second core lacks an air gap.

10. The method of claim 7 , wherein the second core is smaller than the first core.

11. The method of claim 7 , wherein a material of the first core is at least one of:
powdered iron; and
sand dust.

12. The method of claim 7 , wherein a material of the second core is at least one of:
ferrite;
nickel zinc; and
nickel manganese.

13. A portable electronic device, comprising:
a set of components; and
a power supply configured to supply power to the components, wherein the power supply comprises:
a power source;
a nonlinear inductor with an input terminal and an output terminal, further comprising:
a first core; and
a second core connected in series to the first core, wherein the second core has a higher permeability than the first core;
an input switch comprising a control field-effect transistor (FET) configured to couple the input terminal to the power source;
a synchronous FET configured to couple the input terminal to a reference voltage;
an output path comprising a capacitor configured to produce an output voltage and coupled between the output voltage and the reference voltage; and
a control circuit configured to control the input switch to generate the output voltage.

14. The portable electronic device of claim 13 , wherein the second core lacks an air gap.

15. The portable electronic device of claim 13 , wherein the second core is smaller than the first core.

16. The portable electronic device of claim 13 , wherein the power supply is operated using at least one of:
a continuous conduction mode (CCM); and
a discontinuous conduction mode (DCM).

17. The portable electronic device of claim 13 , wherein a material of the first core is at least one of:
powdered iron; and
sand dust.

18. The portable electronic device of claim 13 , wherein a material of the second core is at least one of:
ferrite;
nickel zinc; and
nickel manganese.

Assignees

• Apple Inc

Inventors

• Lee Kisun
• Ye Mao
• Elkayam Shimon

Classifications

• H01F2003/106

  Magnetic circuits using combinations of different magnetic materials · CPC title

• H01F38/023

  of inductances · CPC title

• H01F27/38 Primary

  Auxiliary core members; Auxiliary coils or windings · CPC title

• H01F27/255

  made from particles (H01F27/26 takes precedence) · CPC title

• Y10T307/406

  Cross-Sectional Technologies · mapped topic