Patent ID: 8581438

Claim:
A system for providing power to a powered device, comprising: a communication link power supply path responsive to a first power supply signal received from a communication link, for powering the powered device, an auxiliary power supply path responsive to a second power supply signal from an auxiliary power source, for powering the powered device, a power converter having an input responsive to the second power supply signal, and an output for producing a converter output signal, and a control circuit configured to control the power converter so as to provide power supply switching between the communication link power supply path and the auxiliary power supply path, the power converter being controlled to produce a voltage value at the output of the converter lower than a voltage value from the communication link in order to enable the communication link power supply path to power the powered device, and to produce the voltage value at the output of the converter greater than the voltage value from the communication link in order to enable the auxiliary power supply path to power the powered device.