Abstract: Apparatus and methods for reducing crosstalk in personal audio equipment are provided. In an example, a method to reduce headset audio crosstalk can include applying a first signal to a first speaker channel of a headset, coupling a second speaker channel to a first input of a comparator of a crosstalk compensation circuit using a first switch of the crosstalk compensation circuit, the switch and detect circuit including the crosstalk compensation circuit, coupling a first resistor divider to a second input of the comparator using a second switch of the crosstalk compensation circuit, and adjusting a resistance setting of the first resistor divider from an initial setting using an output of the comparator.

Abstract: This document discusses, among other things, systems and methods to reduce power use of an accessory detection device. The accessory detection device can be configured to be coupled to a mobile device having an audio jack configured to be coupled to a mobile device accessory having a send/end key. In an example, the accessory detection device can include a comparator and a switch. The comparator can be configured to receive mobile device accessory information from the mobile device accessory and to determine activation of the send/end key using the received mobile device accessory information. The switch can be configured to receive connection information indicative of mobile device accessory connection to the audio jack and to isolate a reference input of the comparator from a supply voltage using the connection information, for example, to reduce leakage current.

Abstract: In a general aspect, a power semiconductor device can include a silicon carbide (SiC) substrate and a SiC epi-layer disposed on the SiC substrate. The device can also include a first well region, a second well region disposed in the SiC epi-layer, a first source region disposed in the first well region, and a second source region disposed in the second well region. The device can further include a gate structure disposed on the SiC epi-layer and extending between the first source region and the second source region. The gate structure can include a hybrid gate dielectric. The hybrid gate dielectric can include a first high-k dielectric material and a second high-k dielectric material. The device can also include a conductive gate electrode disposed on the hybrid gate dielectric.

Abstract: Systems and methods are disclosed, including a USB interface detector, a detection method, a USB connector, and an electronic device. The detection method may be applicable to the USB connector mounted in the electronic device. According to an operation mode of the electronic device, a first pin and a second pin in the USB interface can be pulled up or pulled down. After the pull up or the pull down, a voltage change at the first and second pins are detected. If the voltage changes cross a reference voltage, an instruction related to attachment or detachment with a second device can be provided.

Abstract: A synchronous rectifier driver pre-positions a gate of a synchronous rectifier to allow for fast turn-off. The synchronous rectifier driver turns ON the synchronous rectifier by driving the gate at a high level for a period of time that is based on a previous conduction time of the synchronous rectifier. The synchronous rectifier driver thereafter drives the gate at a lower level that is sufficient to keep the synchronous rectifier ON. The synchronous rectifier can be quickly turned OFF by further reducing the level of the drive signal at the gate of the synchronous rectifier.

Abstract: In a general aspect, an apparatus can include a semiconductor substrate, a drift region disposed in the semiconductor substrate; a body region disposed in the drift region and a source region disposed in the body region. The apparatus can also include a gate trench disposed in the semiconductor substrate. The apparatus can further include a gate dielectric disposed on a sidewall and a bottom surface of the gate trench, the gate dielectric on the sidewall defining a first interface with the body region and the gate dielectric on the bottom surface defining a second interface with the body region. The apparatus can still further include a gate electrode disposed on the gate dielectric and a lateral channel region disposed in the body region, the lateral channel region being defined along the second interface.

Abstract: A paddle board includes an electronic marker circuit configured to indicate at least one capability of a cable assembly to a device coupled to the cable assembly and to select the device as one of a source or a sink, the paddle board being powered by the device, a register configured to store at least one variable value associated with at least one of the cable assembly and the paddle board, and a temperature sensor configured to sense a temperature of the paddle board and configured to store a value indicating the sensed temperature in the register.

Abstract: In a general aspect, a charging apparatus can include a power converter circuit configured to supply, from an input voltage, charging power for charging a battery of an electronic device; and a control circuit configured to determine a charging current limit and a charging voltage of the power converter circuit for charging the battery. Determining the charging current limit and the charging voltage can include: setting the current limit of the power converter circuit to an initial charging current limit and setting the charging voltage to an initial charging voltage; determining whether the power converter circuit is operating in a current limit mode or a voltage limit mode; and iteratively modifying the current limit of the power converter circuit until the power converter circuit dithers between the current limit mode and the voltage limit mode.

Abstract: In a general aspect, a packaged semiconductor device can include a semiconductor device and a metal leadframe structure having a signal lead that is electrically coupled with the semiconductor device. The device can also include a molding compound encapsulating at least a portion of the metal leadframe structure. At least a portion of the signal lead can be exposed outside the molding compound. The device can further include a solder plating disposed on exposed portions of the metal leadframe structure. In the device, a flank of the signal lead can have a surface area. At first portion of the surface area of the flank can be defined by the solder plating, and a second portion of the surface area of the flank can be defined by exposed metal of the metal leadframe structure. A perimeter of a surface of the exposed metal can have at least one curved edge.

Abstract: A power converter includes a load detector a processor and a power control block. The load detector is configured to determine a change in a load value of an electronic device coupled to the power converter without receiving a message communicated from the electronic device indicating the change in the load value, and determine if the change in the load value exceeds a threshold value. The processor, in response to determining the change in the load value exceeds the threshold value, is configured to signal the power converter to reduce a voltage. The power control block is configured to reduce the voltage based on the signal.

Abstract: Methods and apparatus for calibrating an audio system including headset coupled to an electronic device via an audio dongle. In an example, a circuit configured to couple a Universal Serial Bus (USB) audio dongle with an audio circuit of an electronic device can include a first impedance configured to couple with a first audio channel of the audio circuit, a second impedance coupled in series with the first impedance and configured to couple with a second audio channel of the audio circuit, a third impedance coupled to a ground sense channel and to a node common to the first impedance and the second impedance, and a controller configured to initiate a first signal on the first channel, to monitor crosstalk of the first signal on the second audio channel and to adjust a setting of the third impedance to reduce the crosstalk.

Abstract: A capacitor input circuit for a mobile power supply includes a bulk capacitor and a switch. The switch connects the bulk capacitor to receive a rectified AC voltage from a rectifier when an AC line voltage input to the mobile power supply is lower than a threshold voltage. When the AC line voltage is greater than the threshold voltage, the switch electrically floats the bulk capacitor.

Abstract: In at least one general aspect, an apparatus can include a first field effect transistor (FET) device and a second FET device. The apparatus can include a characterization circuit coupled to the first FET device and the second FET device where the characterization circuit can be configured to characterize a responsiveness of each of the first FET device and the second FET device. The apparatus can include a balancer configured to produce a modified gate drive signal for the first FET device based on the responsiveness of the first FET device.

Abstract: This document discusses, among other things, a protection system and method configured to detect a parasitic impedance between first and second pins of a standard connector and to remove a current path between a power source and a supply pin of the standard connector if a low-impedance is detected, in certain examples, without adding a current sense resistance to a return path between a ground pin of the standard connector and the power source.

Abstract: In a general aspect, a circuit for controlling operation of an ignition circuit including an insulated-gate bipolar transistor (IGBT) device can include a current slope detection circuit configured to detect a slope of a current in a primary winding of an ignition coil included in the ignition circuit and a driver circuit coupled with the current slope detection circuit. The current slope detection circuit can be further configured to, during charging of the ignition coil, if the detected slope is above a first limit, provide a first indication to the driver circuit; and, if the detected slope is below a second limit, provide a second indication to the driver circuit. The driver circuit can be configured to, in response to receiving the first indication or the second indication, modify operation of the ignition circuit.

Abstract: An active clamp flyback controller includes first and second input terminals, a clamp voltage detection circuit, and an overvoltage protection circuit. The first input terminal is adapted to be coupled to a terminal of a clamp capacitor. The second input terminal receives a feedback signal proportional to a voltage across an auxiliary winding of a flyback transformer. The clamp voltage detection circuit is coupled to the first and second input terminals, and detects a clamp voltage as a difference between a voltage at the first input terminal and an input voltage, the clamp voltage detection circuit calculating the input voltage using a signal from the second input terminal. The overvoltage protection circuit is coupled to the clamp voltage detection circuit for comparing the clamp voltage to a threshold and triggering a protection operation if the clamp voltage is greater than the threshold.

Abstract: In a general aspect, an apparatus can include a leadframe including a plurality of leads configured to be coupled with a printed circuit board. The plurality of leads can be disposed along a single edge of the apparatus. The apparatus can also include an assembly including a substrate and a plurality of semiconductor die disposed on the substrate. The assembly can being mounted on the leadframe. The apparatus can further include an inductor having a first terminal and a second terminal. The first terminal of the inductor can being coupled with the leadframe via a first contact pad, and the second terminal of the inductor can be coupled with the leadframe via a second contact pad. The leadframe, the assembly and the inductor can be arranged in a stacked configuration.

Abstract: In a general aspect, an ignition circuit can include a control circuit configured to receive a command signal from an engine control unit, and a driving circuit coupled with the control circuit. The driving circuit can be configured to be coupled with a resonant circuit that includes a primary winding of an ignition coil. The control circuit and the driving circuit can be configured, in response to a command signal, to drive the resonant circuit at a first frequency to generate a voltage in the ignition coil to initiate a spark in a spark plug; and, in response to the spark being initiated in the spark plug, drive the resonant circuit at a second frequency to maintain the spark in the spark plug for combustion of a fuel mixture. The control circuit can be configured to, after the combustion of the fuel mixture, to disable the driving circuit.

Abstract: A device includes an interface configured to couple a power source to the device. The interface includes a plurality of contacts including at least one first contact configured to couple a voltage bus of the power source to a voltage bus of the device, and at least one second contact configured to couple the voltage bus of the power source to a secondary bus of the device. The device further includes a detector configured to determine a contact resistance of the at least one first contact based on a first current associated with the voltage bus and a second current associated with the secondary bus.

Abstract: In a general aspect, a circuit can include a comparison stage including a plurality of transistors and a current mirror stage including a current mirror. The comparison stage can be configured to produce a cancelling signal before a main signal is produced by the current mirror stage.