Abstract: In a Power over Ethernet (PoE) system, a Powered Device (PD) having circuitry to measure the load current from a Power Sourcing Equipment (PSE) in the PD. Circuitry compares the measured load current with a first threshold. Circuitry automatically generates load pulses for signaling the PSE, that power to the PD should be maintained.

Abstract: In a Power over Ethernet (PoE) system, a Powered Device (PD) having circuitry to measure the load current from a Power Sourcing Equipment (PSE) in the PD. Circuitry compares the measured load current with a first threshold. Circuitry automatically generates load pulses for signaling the PSE. The pulse widths of the load pulses are measured and the widths are automatically adjusted, that power to the PD should be maintained.

Abstract: Methods and devices for detecting USB devices attached to a USB charging port including a USB port having a first data line D+, a second data line D?, and a power line are disclosed. A USB device is attached to the USB port; applying power to the USB device by the power line; applying a first voltage to the line D+ at the USB port by a first impedance; applying a second voltage to the line D? at the USB port by a second impedance. The voltages on the line D+ and the line D? are then monitored at the USB port. If the voltage on the line D+ is approximately equal to a first predetermined value for a predetermined period and the voltage on the line D? is below a second predetermined value, then the USB device is determined to be of an alpha type device.

Abstract: One example includes a power-over-Ethernet (PoE) control system. The system includes a powered device (PD) that is configured to receive a voltage signal via an Ethernet connection and which comprises a PoE signal receiver configured to indicate a nominal power level via the received voltage signal. The system also includes a power sourcing equipment (PSE) device configured to generate the voltage signal and to measure a class current of the voltage signal to determine the nominal power level. The PSE device includes a PoE controller configured to provide a power setting command as a function of the nominal power level to the PoE signal receiver via the voltage signal, such that the PD can operate at a power level that is based on the power setting command.

Abstract: A power-over-Ethernet (PoE) apparatus is provided with PSE controllers that are cooperable to manage a global power budget of the PoE apparatus automatically. Information indicative of the global power budget is conveyed to a group of PSE controllers. The PSE controllers cooperate collectively to allocate the global power budget among themselves automatically and autonomously. This is accomplished in simple fashion without using a separate, programmed microcontroller. Each PSE controller also manages its own local power budget, allocating available local power among its own power sourcing ports.

Abstract: Circuits and methods for providing power from power sourcing equipment to a powered device using an ethernet cable are disclosed herein. An embodiment of the method includes detecting a resistance value in the powered device, wherein the resistance value determines whether the powered device can receive power. A first class event is performed to determine the class of the powered device. A second class event is then performed to determine the class of the powered device. Power is transmitted on all four pairs of the ethernet cable simultaneously when the first and second class events indicate that the class of the powered device conforms to a class that can receive power from the power sourcing equipment on all four pairs.

Abstract: Methods and devices for detecting USB devices attached to a USB charging port including a USB port having a first data line D+, a second data line D?, and a power line are disclosed. A USB device is attached to the USB port; applying power to the USB device by the power line; applying a first voltage to the line D+ at the USB port by a first impedance; applying a second voltage to the line D? at the USB port by a second impedance. The voltages on the line D+ and the line D? are then monitored at the USB port. If the voltage on the line D+ is approximately equal to a first predetermined value for a predetermined period and the voltage on the line D? is below a second predetermined value, then the USB device is determined to be of an alpha type device.

Abstract: Methods and devices for detecting USB devices attached to a USB charging port including a USB port having a first data line D+, a second data line D?, and a power line are disclosed. A USB device is attached to the USB port; applying power to the USB device by the power line; applying a first voltage to the line D+ at the USB port by a first impedance; applying a second voltage to the line D? at the USB port by a second impedance. The voltages on the line D+ and the line D? are then monitored at the USB port. If the voltage on the line D+ is approximately equal to a first predetermined value for a predetermined period and the voltage on the line D? is below a second predetermined value, then the USB device is determined to be of an alpha type device.

Abstract: Disclosed examples include redundant Power over Ethernet (PoE) systems, powered device (PD) controllers and methods in which a first PD controller sends a signal to indicate to the other PD controllers that the first PD controller is powered, and a second PD controller newly connected or reconnected to a corresponding power sourcing equipment (PSE) refrains from turning off a shared DC-DC converter, and the second PD controller waits to allow an inrush current delay of the corresponding PSE to complete before allowing current flow between the DC-DC converter and the corresponding PSE, and the second PD controller selectively provides a signal to request an application circuit powered by the DC-DC converter to temporarily reduce its power consumption below a predetermined value if the corresponding PSE is configured to provide no more than the predetermined value of power.

Abstract: A power-over-Ethernet (PoE) apparatus is provided with PSE controllers that are cooperable to manage a global power budget of the PoE apparatus automatically. Information indicative of the global power budget is conveyed to a group of PSE controllers. The PSE controllers cooperate collectively to allocate the global power budget among themselves automatically and autonomously. This is accomplished in simple fashion without using a separate, programmed microcontroller. Each PSE controller also manages its own local power budget, allocating available local power among its own power sourcing ports.

Abstract: In a Power over Ethernet (PoE) system, a Powered Device (PD) having circuitry to measure the load current from a Power Sourcing Equipment (PSE) in the PD. Circuitry compares the measured load current with a first threshold. Circuitry automatically generates load pulses for signaling the PSE, that power to the PD should be maintained.

Abstract: Methods and devices for detecting USB devices attached to a USB charging port including a USB port having a first data line D+, a second data line D?, and a power line are disclosed. A USB device is attached to the USB port; applying power to the USB device by the power line; applying a first voltage to the line D+ at the USB port by a first impedance; applying a second voltage to the line D? at the USB port by a second impedance. The voltages on the line D+ and the line D? are then monitored at the USB port. If the voltage on the line D+ is approximately equal to a first predetermined value for a predetermined period and the voltage on the line D? is below a second predetermined value, then the USB device is determined to be of an alpha type device.

Abstract: One example includes a power-over-Ethernet (PoE) control system. The system includes a powered device (PD) that is configured to receive a voltage signal via an Ethernet connection and which comprises a PoE signal receiver configured to indicate a nominal power level via the received voltage signal. The system also includes a power sourcing equipment (PSE) device configured to generate the voltage signal and to measure a class current of the voltage signal to determine the nominal power level. The PSE device includes a PoE controller configured to provide a power setting command as a function of the nominal power level to the PoE signal receiver via the voltage signal, such that the PD can operate at a power level that is based on the power setting command.

Abstract: Power over Ethernet (PoE) communication systems, control circuits and methods are presented for controlling power delivered to a powered device through a communication cable, in which a power sourcing equipment measures a supply voltage and selectively discontinues provision of power from a power source in response to a measured supply current exceeding an adaptive limit signal representing a supply current level corresponding to a predetermined safe operating power level at the measured supply voltage.

Abstract: Methods and devices for detecting USB devices attached to a USB charging port are disclosed. The USB charging port includes a USB port having a first data line D+, a second data line D?, and a power line. A method includes attaching the USB device to the USB port; applying power to the USB device by way of the power line; applying a first voltage to the line D+ at the USB port by way of a first impedance; applying a second voltage to the line D? at the USB port by way of a second impedance. The voltages on the line D+ and the line D? are then monitored at the USB port. If the voltage on the line D+ is approximately equal to a first predetermined value for a predetermined period and the voltage on the line D? is below a second predetermined value, then the USB device is determined to be of an alpha type device.

Abstract: One embodiment of the present invention includes a communication network comprises a communication cable having a first wire pair and a second wire pair that both extend between a first end and a second end of the communication cable. The network also comprises at least one power source configured to provide a first supply current through the first wire pair and a second supply current through the second wire pair at the first end of the communication cable. The first supply current and the second supply current can be substantially equal. The network also comprises a first diode bridge and a second diode bridge coupled to the second end of the communication cable and configured to combine the first and second supply currents to provide a combined supply current. The network further comprises a powered device configured to receive the combined supply current.

Abstract: A detection system to detect disconnection of a powered device from a link of a power over Ethernet system is disclosed. The detection system can include closed-loop control configured to supply a predetermined test current to an electrically conductive path that includes at least a portion of the link via which the powered device is connectable for receiving power. A detector is configured to monitor the closed-loop control, the loop detector providing a disconnect signal if the closed-loop control is outside of expected operating parameters, thereby indicating that the powered device has been disconnected from the link.

Abstract: A method of communicating scrambling seed information includes obtaining raw data to be transmitted using a processor, and generating scrambled data from the raw data according to a scrambling seed. A scrambled data packet structure is configured by combining a preamble portion, a synch portion, and a header portion to the scrambled data, wherein the header portion includes a scrambler field value including a plurality of bits (M). The scrambled data packet structure is transmitted to a receiver. The receiver receives the header portion including the scrambler field value. The receiver maps the scrambler field value to a scrambling seed, and decodes the scrambled data using the scrambling seed.

Abstract: Methods and devices for detecting USB devices attached to a USB charging port are disclosed. The USB charging port includes a USB port having a first data line D+, a second data line D?, and a power line. A method includes attaching the USB device to the USB port; applying power to the USB device by way of the power line; applying a first voltage to the line D+ at the USB port by way of a first impedance; applying a second voltage to the line D? at the USB port by way of a second impedance. The voltages on the line D+ and the line D? are then monitored at the USB port. If the voltage on the line D+ is approximately equal to a first predetermined value for a predetermined period and the voltage on the line D? is below a second predetermined value, then the USB device is determined to be of an alpha type device.