Abstract: A method for selectively granting access to an access-controlled space includes obtaining an image of the person requesting access using a camera that is located inside the access-controlled space, and permitting an authorized user of the access-controlled space to grant authorization using the image.

Abstract: An alternating current (AC) to direct current (DC) power converter may have a connector with a pair of power supply contacts and a pair of data contacts. An electronic device may be connected to the connector of the power converter. The power converter may supply DC power to the electronic device using the power supply contacts. The power converter may include control circuitry that has a resistor coupled across the data contacts. When the electronic device and the power converter are connected to each other, each may advertise to the other that capabilities are present that exceed industry standards. At the same time, standard-compliant discovery operations may be performed to probe the value of the resistance of the resistor that is coupled across the data contacts. When extended capabilities are discovered, extended functions may be performed including accelerated charging functions and data communications functions.

Abstract: Systems and methods detecting cable connectivity in a smart home environment are provided, including controlling, at a controller, an output of a notification when a condition is determined based on at least one signal received by the controller, converting, at a power converter coupled to a power source, power received by the power source for the controller, coupling, at a cable having at least one connector that includes a plurality of pins, the power converter and the controller together, and providing the converted power via a power pin and the at least one signal via an identification pin to the controller, and outputting, at the controller, the notification based on a determination that there is a power outage with the power supply or that the power converter is disconnected from the power source based on a detected output level of the at least one signal.

Abstract: The disclosed embodiments provide a system that facilitates the use of a portable electronic device. During operation, the system detects a coupling of a power supply to the portable electronic device through a set of wires. Next, the system uses the set of wires to identify a type of the power supply. The system then periodically determines a switching frequency of the power supply based on the type of the power supply and a current drawn from the power supply. Finally, the system uses the switching frequency to facilitate the operation of a touch control in the portable electronic device. For example, if the switching frequency corresponds to a sensing frequency of the touch control, the system may change the sensing frequency to an alternative sensing frequency.

Abstract: A power supply with reduced electromagnetic interference (EMI) is described. This power supply includes cascaded stages with switched-mode power-supply circuits that are switched synchronously during operation by switching signals that have a common fundamental frequency. EMI associated with the power supply is reduced by establishing a phase shift between the switching signals in at least two of the stages.

Abstract: An electronic device has an I/O port, a bus connector and a transistor that is connected between the I/O port and a communications contact of the bus connector. A control circuit is connected to the transistor to maintain a gate voltage of the transistor independent of power supply voltage on a power supply contact of the connector. Other embodiments are also described and claimed.

Abstract: The disclosed embodiments provide a system that operates switched-mode power supplies, such as flyback converters. The power supplies may comprise isolated or non-isolated power converters. During operation, the system senses an on-time of a primary switch in the power converter. Upon detecting that the on-time does not exceed an on-time threshold within a first pre-specified period that spans one or more switching cycles, the system extends the on-time during a subsequent switching cycle to at least meet the on-time threshold. The system may then measure the voltage on one or more reference windings of the power converter during the on-time of the subsequent switching cycle, wherein the reference winding may comprise, e.g., an auxiliary winding of the primary winding of the power converter or a secondary winding of the power converter (e.g., in the case of isolated power converters utilizing a transformer).

Abstract: Power converters are provided that convert alternating current (AC) power to direct current (DC) power. A power converter may have multiple ports. Each port may have an associated connector with multiple power and data terminals. When an electronic device is connected to a given port, the electronic device draws DC power from the power converter. To ensure that the capacity of the power converter is not exceeded when multiple devices are connected to the ports of the power converter, the power converter may actively monitor its ports for active loads. Load detection circuitry can determine what number of ports are active. Control circuitry can compute a per-port available DC power level based on the number of active ports and can provide this information to connected devices.

Abstract: Systems and methods detecting cable connectivity in a smart home environment are provided, including controlling, at a controller, an output of a notification when a condition is determined based on at least one signal received by the controller, converting, at a power converter coupled to a power source, power received by the power source for the controller, coupling, at a cable having at least one connector that includes a plurality of pins, the power converter and the controller together, and providing the converted power via a power pin and the at least one signal via an identification pin to the controller, and outputting, at the controller, the notification based on a determination that there is a power outage with the power supply or that the power converter is disconnected from the power source based on a detected output level of the at least one signal.

Abstract: The disclosed embodiments provide an AC/DC power converter that converts an AC input voltage into a DC output voltage. This AC/DC power converter includes an input rectifier stage which rectifies an AC input voltage into a first rectified voltage. The AC/DC power converter also includes a switching resonant stage which is directly coupled to the output of the input rectifier stage. The switching resonant stage converts the rectified voltage into a first high frequency AC voltage of a first amplitude. This AC/DC power converter additionally includes a transformer which is coupled to the output of the switching resonant stage and is configured to down-convert the first high frequency AC voltage into a second high frequency AC voltage of a second amplitude. Furthermore, the AC/DC power converter includes an output rectifier stage which is coupled to the output of the transformer, wherein the output rectifier stage rectifies the second high frequency AC voltage into a DC output voltage.

Abstract: An alternating current (AC) to direct current (DC) power converter may have a connector with a pair of power supply contacts and a pair of data contacts. An electronic device may be connected to the connector of the power converter. The power converter may supply DC power to the electronic device using the power supply contacts. The power converter may include control circuitry that has a resistor coupled across the data contacts. When the electronic device and the power converter are connected to each other, each may advertise to the other that capabilities are present that exceed industry standards. At the same time, standard-compliant discovery operations may be performed to probe the value of the resistance of the resistor that is coupled across the data contacts. When extended capabilities are discovered, extended functions may be performed including accelerated charging functions and data communications functions.

Abstract: An alternating current (AC) to direct current (DC) power converter may have a connector with a pair of power supply contacts and a pair of data contacts. An electronic device may be connected to the connector of the power converter. The power converter may supply DC power to the electronic device using the power supply contacts. The power converter may include control circuitry that has a resistor coupled across the data contacts. When the electronic device and the power converter are connected to each other, each may advertise to the other that capabilities are present that exceed industry standards. At the same time, standard-compliant discovery operations may be performed to probe the value of the resistance of the resistor that is coupled across the data contacts. When extended capabilities are discovered, extended functions may be performed including accelerated charging functions and data communications functions.

Abstract: A power supply with reduced electromagnetic interference (EMI) is described. This power supply includes cascaded stages with switched-mode power-supply circuits that are switched synchronously during operation by switching signals that have a common fundamental frequency. EMI associated with the power supply is reduced by establishing a phase shift between the switching signals in at least two of the stages.

Abstract: The disclosed embodiments provide a charging device. The charging device includes a battery, a first physical port and a management apparatus. The management apparatus determines a first type and a first state of a first load device connected to the first physical port and allocates power supplied to the first load device through the first physical port according to the first type and the first state of the first load device.

Abstract: A power converter circuit may convert alternating current signals into direct current signals. A load may be powered from output terminals that are provided with the direct current signals. The power converter circuit may have a transformer with primary and secondary sides. A transistor on the primary side may be controlled using a pulse width modulation controller. A diode may be coupled in series with the secondary side of the transformer and the load. To improve efficiency at larger load currents, a synchronous rectifier control circuit may modulate a transistor on the secondary side that is coupled in parallel with the diode. The synchronous rectifier control circuit may monitor voltage pulses on the transistor on the secondary side or may make direct load current measurements to ascertain how much load current is flowing. Under low or no load conditions, synchronous rectification can be inhibited to improve efficiency.

Abstract: The disclosed embodiments provide a system that facilitates the use of a portable electronic device. During operation, the system detects a coupling of a power supply to the portable electronic device through a set of wires. Next, the system uses the set of wires to identify a type of the power supply. The system then periodically determines a switching frequency of the power supply based on the type of the power supply and a current drawn from the power supply. Finally, the system uses the switching frequency to facilitate the operation of a touch control in the portable electronic device. For example, if the switching frequency corresponds to a sensing frequency of the touch control, the system may change the sensing frequency to an alternative sensing frequency.

Abstract: The disclosed embodiments provide an AC/DC power converter that converts an AC input voltage into a DC output voltage. This AC/DC power converter includes an input rectifier stage which rectifies an AC input voltage into a first rectified voltage. The AC/DC power converter also includes a switching resonant stage which is directly coupled to the output of the input rectifier stage. The switching resonant stage converts the rectified voltage into a first high frequency AC voltage of a first amplitude. This AC/DC power converter additionally includes a transformer which is coupled to the output of the switching resonant stage and is configured to down-convert the first high frequency AC voltage into a second high frequency AC voltage of a second amplitude. Furthermore, the AC/DC power converter includes an output rectifier stage which is coupled to the output of the transformer, wherein the output rectifier stage rectifies the second high frequency AC voltage into a DC output voltage.

Abstract: A power supply with reduced electromagnetic interference (EMI) is described. This power supply includes cascaded stages with switched-mode power-supply circuits that are switched synchronously during operation by switching signals that have a common fundamental frequency. EMI associated with the power supply is reduced by establishing a phase shift between the switching signals in at least two of the stages.

Abstract: Techniques for performing high-voltage charging of electronic devices are provided. A portable device can communicate with a power supply over a data communication line to determine if the power supply is capable of performing the high-voltage charging operation. If yes, the portable device instructs the power supply to provide a specific voltage.

Abstract: The disclosed embodiments provide an AC/DC power converter that converts an AC input voltage into a DC output voltage. This AC/DC power converter includes an input rectifier stage which rectifies an AC input voltage into a first rectified voltage. The AC/DC power converter also includes a switching resonant stage which is directly coupled to the output of the input rectifier stage. The switching resonant stage converts the rectified voltage into a first high frequency AC voltage of a first amplitude. This AC/DC power converter additionally includes a transformer which is coupled to the output of the switching resonant stage and is configured to down-convert the first high frequency AC voltage into a second high frequency AC voltage of a second amplitude. Furthermore, the AC/DC power converter includes an output rectifier stage which is coupled to the output of the transformer, wherein the output rectifier stage rectifies the second high frequency AC voltage into a DC output voltage.