Silicon Laboratories Inc.

John Christopher Gammel

Péter Onódy

Tamás Marozsák

D Matthew Landry

Vince András Horváth

Richard Bruce Webb

John Nathaniel Wilson

Elzbieta A Ledwosinska

William H Simcoe

Endre Kovaks

In some embodiments, a powered device includes a powered device circuit, which may include a maintain power signature (MPS) circuit configured to compare a sense current to a reference current. In a first mode, the MPS circuit may be configured to automatically generate an MPS signal when the sense current is less than the reference current.

Power over ethernet powered device configured for low duty-cycle operation

In some embodiments, powered devices, circuits, and methods are disclosed that may include biasing a hot swap switch to couple a capacitor of a DC-DC converter to negative supply node when an input voltage exceeds a threshold and biasing a telephony switch to couple a positive supply node to a negative supply node when the input voltage exceeds the threshold. Further, the method may further include deactivating the hot swap switch after a period of time, and continuing to bias the telephony switch.

Overvoltage and surge protection in a power over ethernet device

A method includes monitoring total energy supplied, during a power-on phase, to a power field effect transistor (FET) coupled to a network port of a power sourcing equipment (PSE) device using a controller. The method further includes detecting an error when the total energy exceeds a pre-determined threshold.

Power sourcing equipment and method of detecting inrush fault errors

Systems and methods are provided that may be implemented to improve accuracy of relative humidity (RH) determination from dielectric sensing material-based RH sensors, e.g., by decreasing shift and drift effects and compensating for dielectric material aging to improve RH sensor accuracy. The disclosed systems and methods may be implemented to improve RH sensing accuracy by correcting humidity-sensitive electrical parameters (e.g., capacitance, effective resistance, etc.) based on other other measured sensor electrical operating characteristics (e.g., such as real time sensor circuit phase angle) and/or selection of sensor electrical parameters (e.g., such as optimized operating frequency) that are employed for sensing changes in dielectric constant of a dielectric material-based RH sensor.

Systems and methods for humidity measurement using dielectric material-based relative humidity sensors

A gate drive circuit includes a first gate terminal, a second gate terminal, and a driver circuit including an input and including an output coupled to the first gate terminal. The driver circuit is configured to provide a drive signal to the first gate terminal to control a first switch to selectively couple a first current path to a first wire pair of a network port. The gate drive circuit further includes a switch including a first terminal coupled to the output of the driver circuit, a second terminal coupled to the second gate terminal, and a control terminal responsive to a switch control signal to selectively couple the output of the driver circuit to the second gate terminal to control a second switch to selectively couple a second current path to a second wire pair of the network port.

Apparatus including a gate drive circuit for selectively providing power to a powered device through multiple wire pairs

In a particular embodiment, a power sourcing equipment (PSE) device includes at least one network port adapted to couple to a powered device to provide power and optionally data to the powered device via a network cable. The PSE device further includes a current limiter circuit coupled to the at least one network port and having an adjustable threshold. The PSE device also includes a logic circuit coupled to the current limiter circuit and adapted to reduce the adjustable threshold of the current limiter circuit to have a threshold level that is below a nominal operating current level. After a period of time has elapsed during which the current limiter circuit is not activated, the logic circuit is adapted to determine that the powered device is disconnected from the at least one network port.

Circuit device and method of current limit-based disconnect detection

In an embodiment, a power source equipment (PSE) device includes a network port configurable to couple to a network cable and a detection circuit coupled to the network port. The detection circuit is configured to apply a powered device (PD) detection voltage signal including first and second voltages to the network port and to sample a line current of the network port in response to the first and second voltages to detect a complex impedance indicating that a legacy PD is coupled to the network port.

Circuit and method for detecting a legacy powered device in a power over Ethernet system

In an embodiment, a circuit device includes a first counter responsive to a clock signal and to a first control word having a first precision. The counter produces a first control signal related to the first control word at a first output. The circuit device further includes a second counter responsive to the clock signal and to a second control word having the first precision. The second counter produces a second control signal related to the second control word at a second output. The circuit device also includes a filtering circuit responsive to the first output and the second output to receive the first and second control words. The filtering circuit is adapted to produce an output control signal related to the first and second control words, where the output control signal has a second precision that is greater than the first precision.

Circuit device to generate a high precision control signal

A powered device includes a first supply terminal, a second supply terminal, and at least one input pin coupled to the first supply terminal. The powered device further includes an external capacitor having a first terminal coupled to the first supply terminal, a switch coupled to the second supply terminal and coupled to a second terminal of the external capacitor, and power surge detection logic coupled to the switch. The external capacitor is charged in response to a detected power surge that exceeds a threshold.

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Austin, TX, United States of America

John Christopher Gammel