Abstract: In accordance with the teachings described herein, a method and apparatus for handling a charging state in a mobile electronic device is provided. A universal serial bus (USB) interface may be used for connecting the mobile device to a USB host. A processing device may be used to control operation of the mobile device and receive an enumeration acknowledgement signal from the USB host via the USB interface and generate an enable signal upon receiving the enumeration acknowledgement signal. The method and apparatus may further include a rechargeable battery, a battery charger, a timing circuit, and a battery charger enabling circuit.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A system and method for using a universal serial bus (USB) interface in a mobile device is provided that includes providing a battery charger operable to receive a voltage provided at the USB interface, the battery charger operable for charging a battery in the mobile device, and, a voltage regulator operable to receive a voltage provided at the USB interface, the voltage regulator used in powering the mobile device. The method also includes, detecting a USB bus voltage at the USB interface, measuring passage of a predetermined amount of time upon detecting the USB bus voltage, and disabling at least one of the voltage regulator and the battery charger if the predetermined amount of time expires before an enumeration acknowledgement signal is received at the USB interface.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A system and method for using a universal serial bus (USB) interface in a mobile device is provided that includes providing a battery charger operable to receive a voltage provided at the USB interface, the battery charger operable for charging a battery in the mobile device, and, a voltage regulator operable to receive a voltage provided at the USB interface, the voltage regulator used in powering the mobile device. The method also includes, detecting a USB bus voltage at the USB interface, measuring passage of a predetermined amount of time upon detecting the USB bus voltage, and disabling at least one of the voltage regulator and the battery charger if the predetermined amount of time expires before an enumeration acknowledgement signal is received at the USB interface.

Abstract: In accordance with the teachings described herein, a method and apparatus for handling a charging state in a mobile electronic device is provided. A universal serial bus (USB) interface may be used for connecting the mobile device to a USB host. A processing device may be used to control operation of the mobile device and receive an enumeration acknowledgement signal from the USB host via the USB interface and generate an enable signal upon receiving the enumeration acknowledgement signal. The method and apparatus may further include a rechargeable battery, a battery charger, a timing circuit, and a battery charger enabling circuit.

Abstract: In accordance with the teachings described herein, a method and apparatus for handling a charging state in a mobile device is provided. A universal serial bus (USB) interface may be used for connecting the mobile device to a USB host. A processing device may be used to execute programs and to control operation of the mobile device, the processing device may be further operable to receive an enumeration acknowledgement signal from the USB host via the USB interface. A rechargeable battery may be used for powering the processing device. A voltage regulator may be coupled to the USB interface and operable to receive a USB bus voltage from the USB interface and use the USB bus voltage to power the processing device. A timing circuitry may be used to disable the voltage regulator from powering the processing device after a pre-determined amount of time has expired, the timing circuitry being operable to measure the passage of the pre-determined amount of time upon detecting the USB bus voltage.

Abstract: In accordance with the teachings described herein, a method and apparatus for handling a charging state in a mobile electronic device is provided. A universal serial bus (USB) interface may be used for connecting the mobile device to a USB host. A processing device may be used to execute programs and to control operation of the mobile device. The processing device may be operable to receive an enumeration acknowledgement signal from the USB host via the USB interface and generate an enable signal upon receiving the enumeration acknowledgement signal. A rechargeable battery may be used to power the processing device. A battery charger may be used to receive a USB bus voltage from the USB interface and use the USB bus voltage to power the processing device and to charge the rechargeable battery. The battery charger may be further operable to receive a charge enable signal that enables and disables the battery charger from powering the processing device and charging the rechargeable battery.

Abstract: A battery charging circuit comprising: a semiconductor switch having an output connected to a rechargeable battery; a battery charge controller for receiving power from an external source, and supplying output power to a portable device and the input of the semiconductor switch, the current output of the battery charge controller being controllable; and a voltage sensing circuit for: measuring the voltage drop across the battery charge controller; and responding to the voltage drop across the battery charge controller by modulating the semiconductor switch to reduce the quantity of current supplied to the rechargeable battery when the voltage drop is too great; whereby the total power dissipated by the battery charge controller is controlled, the portable device receiving the power it needs to operate and the rechargeable battery receiving any additional available power.

Abstract: A boot-strapped current switch is provided that includes a biasing network, a control signal, a transistor, a control switch and a boot-strapping circuit. The biasing network generates a substantially constant voltage on a biasing network output. The transistor has a control terminal, a first current-carrying terminal, and a second current-carrying terminal, wherein the first current-carrying terminal generates the output current of the current mirror, and the second current-carrying terminal is coupled to a first potential. The control switch is coupled between the biasing network output and the control terminal of the transistor, and is also coupled to the control signal. The control switch couples the first biasing network output to the control terminal of the transistor when the control signal is in a first state. The boot-strapping circuit is coupled between the control terminal of the transistor and a second potential, and is also coupled to the control signal.

Abstract: A boot-strapped current switch is provided that includes a biasing network a control signal, a transistor, a control switch and a boot-strapping circuit. The biasing network generates a substantially constant voltage on a biasing network output. The transistor has a control terminal, a first current-carrying terminal, and a second current-carrying terminal, wherein the first current-carrying terminal generates the output current of the current mirror, and the second current-carrying terminal is coupled to a first potential. The control switch is coupled between the biasing network output and the control terminal of the transistor, and is also coupled to the control signal. The control switch couples the first biasing network output to the control terminal of the transistor when the control signal is in a first state. The boot-strapping circuit is coupled between the control terminal of the transistor and a second potential, and is also coupled to the control signal.