Patent ID: 8332545

Claim:
A USB device, comprising: a battery; at least one port, coupled to the battery, wherein the at least one port is operable to couple to a host USB device which is configured to charge the battery, where the at least one port is configured to receive an enumeration request from the host USB device; device logic, wherein the device logic is configured to perform functionality of the USB device, wherein the device logic is further configured to perform enumeration of the USB device with the host USB device; low power logic, wherein the low power logic is configured to perform enumeration of the low power logic with the host USB device using only power provided by the host USB device; a switch coupled to the at least one port, wherein the switch is configured to couple the device logic to the at least one port via a first USB connection or couple the low power logic to the at least one port via a second USB connection, wherein the switch is configured to: initially couple the low power logic to the at least one port via the second USB connection, wherein after coupling the low power logic to the at least one port, the low power logic is configured to perform enumeration of the low power logic with the host USB device, wherein after enumeration of the low power logic, the low power logic is configured to charge the battery using power provided by the host USB device; receive a signal from the device logic via the first USB connection while the low power logic is coupled to the at least one port via the second USB connection; and in response to the signal, switch from coupling the low power logic to the at least one port via the second USB connection to coupling the device logic to the at least one port via the first USB connection, wherein to switch from coupling the low power logic to the at least one port via the second USB connection to coupling the device logic to the at least one port via the first USB connection the switch is configured to: decouple the low power logic from the at least one port without coupling the device logic to the at least one port; wait for a first period of time, wherein the first period of time is long enough for the host USB device to recognize a disconnection of the low power logic; and after the first period of time, couple the device logic to the at least one port via the first USB connection; wherein after coupling the device logic to the at least one port, the device logic is configured to perform enumeration of the device logic with the host USB device.