Integrated circuit, universal serial bus on-the-go power source and methods for use therewith
View Patent ↗A universal serial bus on-the-go (USB-OTG) power source includes a direct-current to direct-current (DC-to-DC) converter for generating a source voltage when coupled to a battery. A pulse generator generates an oscillating signal when a USB-OTG enable signal is asserted. A power supply module generates a supply voltage from the oscillating signal and the source voltage.
1. A universal serial bus on-the-go (USB-OTG) power source of a USB-OTG device, the power source comprising:
a direct-current to direct-current (DC-to-DC) converter for generating a source voltage when coupled to a battery;
a pulse generator for generating an oscillating signal when a USB-OTG enable signal is asserted by a USB controller of the USB-OTG device when the USB-OTG device is in a host mode; and
a power supply module for generating a supply voltage from the oscillating signal and the source voltage.
2. The USB-OTG power source of claim 1 wherein the power supply module includes:
a first rectifier having an input node that is coupled to the oscillating signal and the source voltage and an output node that is operably coupled to the supply voltage; and
a second rectifier having an input node coupled to the source voltage and an output node that is coupled to the input node of the first rectifier.
3. The USB-OTG power source of claim 1 wherein the oscillating signal includes a pulse width modulated (PWM) signal.
4. The USB-OTG power source of claim 1 wherein the dc-to-dc converter is implemented on an integrated circuit.
5. The USB-OTG power source of claim 1 wherein the integrated circuit includes an output pad for coupling the oscillating signal to the universal serial bus on-the-go (USB-OTG) power supply when a USB-OTG enable signal is asserted and for coupling an alternative output signal to an alternative off-chip circuit when the USB-OTG enable signal is deasserted.
6. An integrated circuit comprising:
an output pad for coupling an oscillating signal to a universal serial bus on-the-go (USB-OTG) power supply when a USB-OTG enable signal is asserted and for coupling an alternative output signal to an alternative off-chip circuit when the USB-OTG enable signal is deasserted, wherein the oscillating signal includes a pulse width modulated (PWM) signal.
7. An integrated circuit comprising:
an output pad for coupling an oscillating signal to a universal serial bus on-the-go (USB-OTG) power supply when a USB-OTG enable signal is asserted and for coupling an alternative output signal to an alternative off-chip circuit when the USB-OTG enable signal is deasserted; and
a multiplexer module, operably coupled to the output pad for generating a multiplexed output that includes the oscillating signal when the USB-OTG signal is asserted and that includes the alternative output signal when the USB-OTG signal is deasserted.
8. The integrated circuit of claim 7 further comprising:
a pad driver module, operably coupled to the output pad and to the multiplexer module, for driving the multiplexed output on the output pad.
9. A method comprising:
converting a battery voltage to a substantially stable source voltage;
producing an oscillating signal; and
generating a supply voltage from the oscillating signal and the source voltage when a USB-OTG enable signal is asserted.
10. The method of claim 9 wherein the oscillating signal includes a pulse width modulated (PWM) signal.
11. A method comprising:
coupling an oscillating signal to a universal serial bus on-the-go (USB-OTG) power supply through an output pad of an integrated circuit when a USB-OTG signal is asserted, wherein the oscillating signal includes a pulse width modulated (PWM) signal; and
coupling an alternative output signal to an alternative off-chip circuit through an output pad of an integrated circuit when the USB-OTG signal is deasserted.
12. A method comprising:
coupling an oscillating signal to a universal serial bus on-the-go (USB-OTG) power supply through an output pad of an integrated circuit when a USB-OTG signal is asserted;
coupling an alternative output signal to an alternative off-chip circuit through an output pad of an integrated circuit when the USB-OTG signal is deasserted; and
generating a multiplexed output that includes the oscillating signal when the USB-OTG enable signal is asserted and that includes the alternative output signal when the USB-OTG enable signal is deasserted.