Method and apparatus for handling a charging state in a mobile electronic device
View Patent ↗The present invention is directed at a method of handling a device charging state for a Universal Serial Bus (USB) connected mobile electronic device comprising the steps of sensing a presence of a bus voltage; sensing an enumeration acknowledgement signal between the device and a USB host; and transmitting a signal to instruct the device to enter the device charging state.
1. A method for charging a mobile device, the method comprising:
enabling a battery charger upon coupling the mobile device to a Universal Serial Bus (USB) host; and
disabling the battery charger if enumeration between the mobile device and the USB host is not acknowledged within a first predetermined time.
2. The method of claim 1 , further comprising:
charging the mobile device upon enabling the battery charger, wherein the battery charger begins charging the mobile device before the first predetermined time expires.
3. The method of claim 1 , further comprising:
sensing whether the USB host is supplying voltage to the mobile device; and
entering the mobile device in a charging state upon sensing that the USB is supplying voltage to the mobile device.
4. The method of claim 1 , further comprising:
entering the mobile device in a suspend state upon disabling the battery charger.
5. The method of claim 1 , further comprising:
receiving a high state signal requesting the mobile device to enter a suspend state; and
disabling the battery charger to enter the mobile device in the suspend state.
6. The method of claim 5 , wherein the battery charger is only disabled if a low state signal is not received within a second predetermined time after the high state signal is received.
7. The method of claim 1 , wherein the first predetermined time is at least 100 ms.
8. The method of claim 6 , wherein the second predetermined time is about 150 ms.
9. A Universal Serial Bus (USB) device comprising:
a battery charger operable to charge a mobile device upon the mobile device being connected to a USB host, wherein the battery charger is disabled if enumeration between the mobile device and the USB host is not acknowledged within a first predetermined time.
10. The USB device of claim 9 , wherein the battery charger begins charging the mobile device before the first predetermined period expires.
11. The USB device of claim 9 , further comprising:
a voltage module configured to determine whether the USB host is supplying voltage to the mobile device, wherein the mobile device enters a charging state upon the voltage module determining that the USB is supplying voltage to the mobile device.
12. The USB device of claim 9 , wherein the mobile device enters a suspend state upon the battery charger being disabled.
13. The USB device of claim 9 , wherein the USB host is operable to transmit a high state signal requesting the mobile device to enter a suspend state, wherein the battery charger is disabled to enter the mobile device in the suspend state.
14. The USB device of claim 13 , wherein the battery charger is only disabled if a low state signal is not received within a second predetermined time after the high state signal is received.
15. The USB device of claim 9 , wherein the first predetermined time is at least 100 ms.
16. The USB device of claim 14 , wherein the second predetermined time is about 150 ms.