CHARGING SYSTEM

• US 20090195214A1
• Filed: 01/28/2009
• Published: 08/06/2009
• Est. Priority Date: 01/28/2008
• Status: Abandoned Application

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments Deutschland Gesellschaft Mit Beschrã¤Nkter Haftung (Texas Instruments, Inc.)
• Inventors: Scibilia, Roberto, Gehrke, Dirk
• Application Number:
  US12/361,315
• Publication Number:
  US 20090195214A1
• Time in Patent Office: Days
• US Class Current: 320/137
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 7/00308 Overvoltage protection
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence

Abstract

A mobile electronic device includes circuitry for contactless charging. The circuitry comprises an inductor for contactlessly receiving power and supplying the power to the mobile electronic device. A control stage coupled to the inductor and is adapted to control a supply of power received by the inductor to the load to regulate a load current such that a supply voltage is maintained above a predetermined level.

Claims

1. An apparatus comprising:

an inductor that is adapted to magnetically coupled to power sourcing circuitry;

a rectifier that is coupled to the inductor and that outputs a direct current (DC) signal;

a protection circuit that is coupled to the rectifier and that is adapted to limit the DC signal; and

a controller that is coupled to the protection circuit, that is adapted to output a system voltage and a system current to a load, and that is adapted to output a charging voltage and a charging current to a battery, wherein the controller adjusts the charging voltage and charging current so that the system voltage is maintained above a predetermined threshold.

2. The apparatus of claim 1, wherein the rectifier further comprises a diode bridge.

3. The apparatus of claim 1, wherein the protection circuit provides overvoltage protection and limits the voltage of the DC signal.

4. A system comprising:

power sourcing circuitry having;

a first inductor; and

a switch that is coupled to the first inductor, wherein the first inductor stores energy when the switch is actuated;

a second inductor that is adapted to magnetically coupled to the first inductor, wherein second inductor receives energy from the first inductor when the switch is deactuated;

a rectifier that is coupled to the second inductor and that outputs a direct current (DC) signal;

a protection circuit that is coupled to the rectifier and that is adapted to limit the DC signal; and

a controller that is coupled to the protection circuit, that is adapted to output a system voltage and a system current to a load, and that is adapted to output a charging voltage and a charging current to a battery, wherein the controller adjusts the charging voltage and charging current so that the system voltage is maintained above a predetermined threshold.

5. The system of claim 4, wherein the power sourcing circuit further comprises:

an inverter that is coupled to the control electrode of the switch and that generates a pulse width modulated (PWM) signal to actuated and deactuate the switch; and

an RCD network that is coupled to an input of the inverter and to the control electrode of the switch.

6. The system of claim 5, wherein the RCD network further comprises:

a capacitor coupled between the input of the inverter and ground;

a first resistor coupled between the control electrode of the switch and the input of the inverter;

a second resistor coupled to the input of the inverter; and

a diode coupled between the second resistor and the control electrode of the switch.

7. The system of claim 4, wherein the power sourcing circuitry further comprises a capacitor that is coupled in parallel to the first inductor.

8. The system of claim 4, wherein the rectifier further comprises a diode bridge.

9. The system of claim 4, wherein the protection circuit provides overvoltage protection and limits the voltage of the DC signal.