APPARATUS AND METHOD FOR A SWITCHING POWER CONVERTER

• US 20130076301A1
• Filed: 09/28/2011
• Published: 03/28/2013
• Est. Priority Date: 09/28/2011
• Status: Active Grant

• Current Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Original Assignee: Integrated Device Technology Incorporated (Renesas Electronics Corporation)
• Inventors: Bastami, Siamak
• Granted Patent: US 9,673,638 B2
• Time in Patent Office: Days
• US Class Current: 320/107
• CPC Class Codes: H02J 7/00041 in response to measured battery parameters, e.g. voltage, current or temperature profile
• CPC Class Codes: H02J 7/00047 with provisions for charging different types of batteries

Abstract

A charging converter includes a plurality of switches configured to switchably operate to either step up an input voltage or step down the input voltage and generate a charging voltage on a second terminal to charge to a rechargeable storage unit, and control logic configured to operate the plurality of switches in one of a step up mode and a step down mode based on a determination of a voltage level of the input voltage relative to the desired charging voltage. A method includes determining a desired charging voltage to charge a rechargeable storage unit, switchably controlling a charging converter to step up the input voltage if an input voltage is lower than the desired charging voltage to generate a charging voltage, and switchably controlling the charging converter to step down the input voltage if the input voltage is higher than the desired charging voltage to generate the charging voltage.

Claims

1. A charging converter, comprising:

a first terminal configured to receive an input voltage;

a plurality of switches configured to switchably operate to either step up the input voltage or step down the input voltage and generate a charging voltage on a second terminal to charge to a rechargeable storage unit; and

control logic configured to operate the plurality of switches in one of a step up mode and a step down mode based, at least in part, on a determination of a voltage level of the input voltage relative to the desired charging voltage.

2. The charging converter of claim 1, further comprising an inductor and a capacitor, wherein the plurality of switches includes a first switch, a second switch, a third switch, and a fourth switch, and wherein the first switch, the second switch, the inductor and the capacitor are configured in a buck configuration, and the inductor, the capacitor, the third switch, and the fourth switch are configured in a boost configuration.

3. The charging converter of claim 1, wherein the plurality of switches are further configured to switchably operate to either step up or step down a voltage from the rechargeable storage unit in response to the control logic to charge an external electronic device.

4. The charging converter of claim 1, further comprising a current sense element coupled between the plurality of switches and the rechargeable storage device, the current sense element having current sense feedback signals input into the control logic.

5. The charging converter of claim 4, wherein the control logic is configured to hold at least one of the plurality of switches open in response to a determination that a current flowing through the current sense element exceeds a pre-determined threshold.

6. The charging converter of claim 1, wherein the control logic is configured to control the plurality of switches to charge the rechargeable storage unit in at least one of a constant current mode and a constant voltage mode.

7. An electronic device, comprising:

a charging converter coupled in a current path from a first terminal to a second terminal providing power from a power source to a rechargeable storage unit;

a system power converter coupled in a current path from the second terminal to a third terminal providing power to internal system components of the electronic device; and

control logic configured to control the charging converter to switchably operate in a plurality of different modes in response to a determination of a voltage from the power source relative to a desired charging voltage for the rechargeable storage unit.

8. The electronic device of claim 7, wherein the system power converter is coupled to an output of the charging converter and in series with the charging converter.

9. The electronic device of claim 7, wherein the system power converter is coupled to the first terminal and in parallel with the charging converter.

10. The electronic device of claim 7, wherein the rechargeable storage unit is selected from the group consisting of a single cell battery and a multiple cell battery.

11. The electronic device of claim 7, wherein the plurality of different modes includes a step up mode and a step down mode.

12. The electronic device of claim 11, wherein the plurality of different modes further includes at least one of an on-the-go mode and a protection mode.

13. The electronic device of claim 7, wherein the control logic is further configured to control the system power converter to switchably operate in either a step up mode or a step down mode in response to a determination of a voltage received by the system power converter relative to a desired system voltage.

14. The electronic device of claim 7, wherein the charging converter includes:

a first plurality of switches configured in a buck configuration with an inductor and a capacitor; and

a second plurality of switches configured in a buck configuration with the inductor and the capacitor.

15. The electronic device of claim 14, wherein the first plurality of switches is configured in another boost configuration with the inductor and another capacitor, and wherein the second plurality of switches is configured in another buck configuration with the inductor and the another capacitor, the first plurality of switches and the second plurality of switches operating in one of the another buck configuration and the another boost configuration while providing power from the rechargeable storage unit to the external electronic device.

16. A method for charging a rechargeable storage unit of an electronic device, the method comprising:

receiving an input voltage provided by a power source;

determining a desired charging voltage to charge a rechargeable storage unit;

switchably controlling a charging converter to step up the input voltage if the input voltage is lower than the desired charging voltage to generate a charging voltage; and

switchably controlling the charging converter to step down the input voltage if the input voltage is higher than the desired charging voltage to generate the charging voltage.

17. The method of claim 16, further comprising switchably controlling a system power converter to perform at least one of a step up and a step down function on the charging voltage to power internal system components during charging of the rechargeable storage unit.

18. The method of claim 17, further comprising the rechargeable storage unit supporting powering the internal system components through the system power converter when no input voltage is provided by the power source.

19. The method of claim 17, further comprising:

sensing a current flowing from the rechargeable storage unit through a current sense element; and

controlling at least one of the charging converter and the system power converter to hold open a current path if the current is above a pre-determined threshold.

20. The method of claim 16, further comprising:

determining another desired charging voltage to charge an external electronic device;

switchably controlling the charging converter to step up a voltage from the rechargeable storage unit if the voltage is lower than the another desired charging voltage to generate another charging voltage to the external electronic device; and

switchably controlling the charging converter to step down the voltage from the rechargeable storage unit if the voltage is higher than the another desired charging voltage to generate the another charging voltage to the external electronic device.

21. The method of claim 16, wherein receiving an input voltage provided by a power source includes receiving an input voltage from a power source through coupling selected from the group consisting of wired connection coupling and wireless power coupling.

22. The method of claim 16, wherein the wired connection coupling includes at least one of an AC/DC adaptor and a universal serial bus connector.