Abstract: An RF transmitter (1) having a gate-segmented power output stage (2) and a digital driver (5). The gate-segmented power output stage (2) includes a field-effect transistor with a plurality of gate fingers (32) and drain fingers (31) that define a gate periphery. The field-effect transistor comprises a plurality of power output stage segments (3) that each correspond to a respective part of the gate periphery, and that each have a respective power output stage segment input (4). The digital driver (5) has control outputs (6) which are connected to corresponding ones of the respective power output stage segment inputs (4), and is configured for individually switching each of the power output stage segments (3) between an on mode and a cut-off mode in dependence of one or more input signals to obtain a modulated RF carrier signal at an output (7) of the gate-segmented power output stage (2).

Abstract: An abnormal current protection device includes an overcurrent protector and a controller, and the overcurrent protector includes a short-circuit detection unit and an overcurrent detection unit. The short-circuit detection unit is configured to detect whether there is a short-circuit event within a period of debounce time of a protection cycle. The overcurrent detection unit is configured to detect whether there is an overcurrent event after the period of debounce time within the protection cycle. The controller is configured to disable a converter when the short-circuit event is detected, and disable a power stage when the overcurrent event is detected.

Abstract: An audio signal modulation and amplification circuit includes a common-mode electric potential controller, a carrier generator, and channel circuits. The common-mode electric potential controller is configured to generate one or more first common-mode electric potentials and second common-mode electric potentials. The carrier generator is adapted to receive the first common-mode electric potential to generate a carrier signal. Each of the channel circuits includes a filter, a comparison circuit, and a driving circuit. The filter is adapted to filter an input signal and generate a filtered signal based on a corresponding one of the second common-mode electric potentials. The comparison circuit is configured to compare the potential of the carrier signal with the potential of the filtered signal to generate a pulse-width modulation signal. The driving circuit is configured to be turned on or off in response to the pulse-width modulation signal to output a load driving signal.

Abstract: The invention relates to a method for controlling a driver circuit. The method comprises operating an amplifier for providing an output signal, for example an electronic signal for driving or controlling a load, for example a voltage or a current, based on a control signal. The method further comprises operating a comparator for providing the control signal by comparing an input signal, for example an electronic signal with a lower level or a lower amplitude than the output signal, to a feedback signal, wherein the feedback signal is based on the output signal. The method further comprises providing a first supply voltage to the comparator, and providing a second supply voltage to the amplifier, wherein the second supply voltage is higher than the first supply voltage.

Abstract: An uninterruptible power supply (UPS) converter circuit includes a controlled switching element, a filter capacitor, and a split DC capacitor comprising a plus DC capacitor and a minus DC capacitor split at a DC-link mid-point, connected to each other at the DC-link mid-point on a respective first side. A second side of the input filter capacitor at an AC point is coupled via an inductor element to a second side of the controlled switching element, the second side of the controlled switching element being coupled to the second side of the plus DC capacitor and the minus capacitor. The controlled switching element operates is configured to be controlled such that a current from the AC point via the inductor element flows alternatingly to either the plus DC output capacitor or the minus DC capacitor, and to the DC-link mid-point, respectively, thereby discharging the input filter capacitor.

Abstract: A balun includes a first winding which has a first terminal coupled to an input, and a second terminal coupled to a reference potential terminal. The balun includes a second winding magnetically coupled to the first winding. The second winding has a first terminal coupled to a first differential output, a second terminal coupled to a second differential output, and a tap coupled to the reference potential terminal. The balun includes a first capacitor which has a first terminal coupled to the first winding and a second terminal coupled to the second winding. The balun includes a third winding which has a first terminal coupled to the reference potential terminal and a floating second terminal. The balun includes a second capacitor which has a first terminal coupled to the third winding and a second terminal coupled to the second winding.

Abstract: There is provided an electronic device including a switching element unit that applies a voltage based on a direct-current power supply to one end of an electroacoustic converter in response to a first pulse signal and applies a voltage based on the direct-current power supply to another end of the electroacoustic converter in response to a second pulse signal, and a delay circuit that generates a delay based on a communication frequency in at least one of the first pulse signal and the second pulse signal.

Abstract: In certain examples, the disclosure involves or is directed to a circuit-based apparatus that has a T-network, and a plurality of circuit paths with a first path having a first switching node to respond to an RF input signal that is characterized by a first phase, and with a second path having a second switching node to respond to the RF input signal characterized by a second phase that is different than the first phase. The circuit paths may be configured as a push-pull amplification circuit. The T-network may be arranged between the first and second switching nodes and may include a variable impedance circuit. The variable impedance circuit may be adjusted, in accordance with a selected frequency of the RF input signal. The T-network may be characterized by a resonance frequency shunts a second harmonic current associated with the resonance frequency, thereby permitting for use of different selected frequencies.

Abstract: An amplifier circuit includes a constant current circuit for outputting a constant current signal at its output terminal, an operational amplifier for outputting an amplified control signal based on the first voltage signal, and an amplified voltage output circuit for outputting a second voltage signal based on both the constant current signal and the amplified control signal. The constant current circuit has a light-emitting device having one end supplied with the constant voltage signal and another end supplied with ground potential, a light responsive electricity generating device for outputting a drive signal in response to light emitted by the light-emitting device, a first transistor generating the constant current signal based on the amplified voltage signal applied thereto and to output the constant current signal; and a current control circuit for detecting the value of the constant current signal and controlling the supply of the drive signal based on the detection.

Abstract: A driving circuit of a loudspeaker includes a periodic signal generation circuit, a signal processing circuit, a class-D amplifier circuit, a current sensing circuit, and a sample and hold circuit. The periodic signal generation circuit is arranged to generate a periodic signal and a control signal. The signal processing circuit is coupled to the periodic signal generation circuit, and is arranged to generate a pre-driving signal. The class-D amplifier circuit is coupled to the signal processing circuit, and is arranged to drive the loudspeaker according to the pre-driving signal. The current sensing circuit is coupled to the class-D amplifier circuit, and is arranged to generate a current sensing signal. The sample and hold circuit is coupled to the periodic signal generation circuit and the current sensing circuit, and is arranged to sample and hold the current sensing signal according to the control signal, to generate a current sampling signal.

Abstract: In certain aspects, an apparatus includes a first amplifier having a first output and a second output, and a transformer. The transformer includes a first switchable inductor coupled between the first output and the second output, a first capacitor coupled in parallel with the first switchable inductor, a second switchable inductor magnetically coupled to the first switchable inductor, a second capacitor coupled in parallel with the second switchable inductor, a third switchable inductor magnetically coupled to the first switchable inductor, and a third capacitor coupled in parallel with the third switchable inductor.

Abstract: Disclosed in the present invention are a wireless power and data synchronous transfer system and a data modulation method, wherein a power/information complex modulation is carried out on a primary side front converter and a secondary side back converter, and output power/information flow can be transmitted across the wireless power transfer circuit, thus realizing communication between the primary side and the secondary side. With the method of the present invention, by modulating a digital frequency band signal to a direct current bus, frequency mixing effect of an inverter/rectifier circuit is utilized to move a spectrum of modulated digital signal to a frequency near a power transfer frequency and then the modulated digital signal is transmitted to a circuit on the other side, and the circuit on the other side demodulates the signal to obtain a baseband signal. The present invention has wide applicability and can be used in various wireless power transfer systems, especially for high-frequency systems.

Abstract: The application describes a switched driver (401) for outputting a drive signal at an output node (402) to drive a load such as a transducer. The driver receives respective high-side and low-side voltages (VinH, VinL) defining an input voltage at first and second input nodes and has connections for first and second capacitors (403H, 403L). A network of switching paths is configured such that each of the first and second capacitors can be selectively charged to the input voltage, the first input node can be selectively coupled to a first node (N1) by a path that include or bypass the first capacitor, and the second input node can be selectively coupled to a second node (N2) by a path that includes or bypasses the second capacitor. The output node (402) can be switched between two switching voltages at the first or second nodes. The driver is selectively operable in different operating modes, where the switching voltages are different in each of said modes.

Abstract: A semiconductor device includes: an operational amplifier; an external terminal configured to be attached to an external capacitor; and a resistor configured to be connected between a node, to which an output terminal and an inverting input terminal of the operational amplifier are connected in common, and the external terminal.

Abstract: Described embodiments include an audio amplifier circuit that includes a first amplifier having a differential first amplifier input adapted to be coupled to an audio input source, a multiplexer having first and second mux inputs, a control input and a mux output. The first mux input is coupled to the differential amplifier output. There is a signal generator having a generator input coupled to the mux output. There is also a driver circuit having a driver circuit input and a driver circuit output, the driver circuit input coupled to the generator output, and a second amplifier having a first error input coupled to a current sense terminal that is configured to provide a voltage proportional to a current supplied from a power supply terminal, and a second error input coupled to a current limit terminal configured to provide a reference voltage proportional to a current limit value.

Abstract: An audio amplifier with duty ratio control is provided. The audio amplifier comprises a pulse width modulation modulator, a power stage, and a voltage converter. The pulse width modulation modulator is configured to receive an input signal for generating a pulse width modulation signal. The power stage is configured to output an output signal according to a supply voltage and the pulse width modulation signal. The voltage converter is configured to adjust voltage level of the supply voltage according to the pulse width modulation signal. The audio amplifier is configured to adjust the voltage level of the supply voltage when duty ratio of the pulse width modulation signal is greater than a duty ratio threshold.

Abstract: A radar cloaking apparatus configured for positioning on a radar target and corresponding methods are provided. The radar cloaking apparatus comprises a radio signal emitter and computational circuitry. The computational circuitry is configured to cause the radar cloaking apparatus to at least reference a model encoding scattering properties of the radar target; determine a predicted reflection signature of the radar target from a selected interrogation angle based at least in part on the model encoding the scattering properties of the radar target; and cause transmission, by the radio signal emitter, of a cloaking radio signal along the selected interrogation angle. The cloaking radio signal is actively generated based on the predicted reflection signature of the radar target shifted in phase such that the cloaking radio signal is configured to destructively interfere with a reflected signal formed by an interrogating radar signal scattering off of the radar target.

Abstract: An audio electronic system includes a DC switching converter comprising first and second Zeta converters, each comprising an input stage, an output stage, a first switching stage, and a second switching stage. The input stage of each Zeta converter comprises a respective input inductor having a first terminal electrically coupled to the respective first switching stage. The input inductors of the input stages of the first and second Zeta converters are magnetically coupled in such a way that when current enters the terminal of the input inductor of the first Zeta converter that is coupled to the first switch stage of the first Zeta converter, a voltage induced by the coupled current is positive at the terminal of the input inductor of the second Zeta converter that is coupled to the first switching stage of the second Zeta converter.

Abstract: An amplifier includes an input circuit configured to receive an analog input signal and a feedback signal, and output an analog error signal based on the analog input signal and the feedback signal. An ADC is configured to convert the analog error signal into a digital signal in a phase domain. A digital control circuit is configured to generate a digital control signal based on the digital signal in the phase domain. An output circuit is configured to generate an amplified output signal based on the digital control signal, and a feedback circuit is configured generate the feedback signal based on the amplified output signal.

Abstract: A switching amplifier includes a first portion of a power stage; a second portion of a power stage; a pulse-width modulation (PWM) control loop coupled to control inputs of the first portion of the power stage; and a linear amplifier coupled to control inputs of the second portion of the power stage. The PWM control loop controls a first switch and a second switch of the first portion of the power stage. Between current terminals of the first switch and the second switch is a first signal output of the switching amplifier. The linear amplifier controls a third switch and a fourth switch of the second portion of the power stage. Between current terminals of the third switch and the fourth switch is a second signal output of the switching amplifier.

Abstract: An apparatus and method for improving the efficiency of a D class amplifier, particularly at lower output levels. A class D amplifier having a load with inductance, such as a transducer, is configured to concurrently act as its own buck regulator. A capacitor connected to ground and to both ends of the transducer through switches functions as the buck regulator in connection with the inductance of the transducer, providing the class D amplifier with additional voltage levels such as might be provided by a G/H class amplifier but without the added complexity or expense of the G/H configurations. Better efficiency is possible than that provided by a 100% efficient conventional buck regulator. No envelope detector is required, nor any change to the gain of the digital signal to the class D amplifier. Feedback may be used if desired, but is not required to obtain a high quality output signal.

Abstract: Audio amplifier circuit includes a pulse width modulation circuit, an auxiliary loop circuit corresponding to a first variable resistance value and a first variable current value, and a main loop circuit corresponding to a second variable resistance value and a second variable current value. Main loop circuit is coupled between a second node, an output terminal, and a first node. Under a condition that auxiliary loop circuit and main loop circuit are turned on, second variable resistance value is decreased and second variable current value is increased after auxiliary loop circuit enters into a first control state, such that main loop circuit enters into a second control state. First variable resistance value is increased and first variable current value is decreased after main loop circuit enters into second control state, such that auxiliary loop circuit is out of first control state.

Abstract: A generator for the delivery of high frequency alternating current to a medical instrument has a power supply unit, a high frequency generator primary unit (HF generator primary unit), an application unit, and a control unit. The HF generator primary unit is connected to the power supply unit and the application unit and designed to supply the application unit with high frequency alternating current during operation. The application unit is electrically connected in a switchable manner to connections for connecting a medical instrument via at least one relay. The control unit is galvanically separated from the application unit and designed to control the at least one relay and the application unit as applicable. The control unit is connected to the application unit via an intermediate control circuit, wherein the intermediate control circuit is galvanically separated both from the control unit and from the application unit.

Abstract: A driver circuit includes a drive circuit, a monitoring circuit, and a control circuit. The drive circuit includes a first current source and drives a switching element when the first current source is connected to a control terminal of the switching element. The monitoring circuit monitors a period of time from a start to an end of a change in a voltage drop across the switching element. The control circuit controls a current value of the first current source based on the monitored period of time such that a slew rate of the voltage drop across the switching element approaches a target value.

Abstract: There is provided a RF-DAC that may include (i) a first PAM that includes a first group of first power amplifiers of different amplifications, (ii) a second PAM that includes a second group of second power amplifiers of different amplifications; (iii) a load that includes an output port and a transformer; (iv) power amplifiers control units, and a transformer control unit.

Abstract: An electronic motor control system provides selectable linear and pulse-width modulated (PWM) operation without generating cross-over distortion. The system includes an output stage that has a pair of push-pull drivers each coupled to a terminal of the motor. The electronic motor control system also includes a pulse-width modulated (PWM) driver for providing pulse-width modulated drive signals to an input of the output stage when the pulse-width modulated mode is selected and a linear amplifier stage that provides a linear analog signal to the input of the output stage in linear mode, so that both drivers are operated to supply the current to the motor. In pulse-width modulated mode, a driver is selected for PWM operation, while the other driver is operated to supply a fixed voltage. A feedback control loop senses motor current and provides outputs to the pulse-width modulator and the linear amplifier stage.

Abstract: Described herein is a front-end for a neural recording system that boosts input impedance of the front-end circuit. The front-end includes an amplifier and two choppers. A first input terminal of the first chopper may be coupled to a first output terminal from one or more signal sensors. A first input terminal of the second chopper may be coupled to a second output terminal from the signal sensors. A second input terminal of the first chopper may be coupled to a first output terminal of a feedback subsystem. A second input terminal of the second chopper may be coupled to a second output terminal of the feedback subsystem. The output terminals of each chopper may each be coupled to a different capacitor such that after switching, the voltage of each capacitor remains substantially the same, improving the input impedance of the circuit.

Abstract: A context-aware voice guidance method is provided that interacts with other voice services of a user device. The voice guidance does not provide audible guidance while the user is making a verbal request to any of the voice-activated services. Instead, the voice guidance transcribes its output on the screen while the verbal requests from the user are received. In some embodiments, the voice guidance only provides a short warning sound to get the user's attention while the user is speaking on a phone call or another voice-activated service is providing audible response to the user's inquires. The voice guidance in some embodiments distinguishes between music that can be ducked and spoken words, for example from an audiobook, that the user wants to pause instead of being skipped. The voice guidance ducks music but pauses spoken words of an audio book in order to provide voice guidance to the user.

Abstract: An electronic control system provides selectable linear and pulse-width modulated (PWM) operation with reduced disruption when changing from PWM operation to linear operation. The system includes an output stage that has a push-pull driver coupled to the load, which may be a motor, a haptic device, or other device requiring current-mode control. The system also includes a pulse-width modulated (PWM) driver for providing pulse-width modulated drive signals to gates of the transistors of the output stage when a pulse-width modulated mode is selected, and a linear amplifier stage that provides a linear analog signal to the gates of the transistors when a linear mode is selected. A pre-charging circuit pre-charges the gates during a pre-charge cycle that is initiated when the operating mode changes from the PWM operating more to the linear operating mode.

Abstract: This invention relates to a self-excited oscillation suppression device and method for the power amplifying circuit, belonging to the field of electronic technology. Said power amplifying circuit includes a FET and a feedback loop. Said device includes: a first compensation circuit which is connected between a drain and a gate of the FET and a second compensation circuit which is connected in parallel with a feedback resistor of said feedback loop. It can solve self-excited oscillation caused by deep negative feedback in the existing power amplifying circuit. The first compensation circuit can shift the open-loop gain curve forward as a whole, and the second compensation circuit can speed up the closure of the feedback gain curve and the open-loop gain curve so that the two curves will close up before the self-excited oscillation; the self-excited oscillation will be suppressed, and the stability of the power amplifying circuit will be improved.

Abstract: A pulse width modulated (PWM) amplifier includes a synchronization logic circuit having a first input configured to receive a bridge control signal and having a second input configured to receive a clock signal. The synchronization logic circuit is configured to provide a slope switch signal and a reference switch signal. The PWM amplifier includes a ramp generator having a first input configured to receive a first voltage supply and having a second input configured to receive a second voltage supply and having a third input configured to receive the reference switch signal and having a fourth input configured to receive the slope switch signal. The ramp generator is configured to provide a ramp signal having a first slope responsive to the slope switch signal in a first state and having a second slope responsive to the slope switch signal in a second state and to provide the clock signal.

Abstract: A feedforward correction block for use in a multi-level output system may include circuitry configured to determine an occurrence of a mode transition between operating modes of the multi-level output system, capture a loop filter output of a signal path of the multi-level output system occurring before and after the occurrence of the mode transition, and based on the transition and a change in the loop filter output responsive to the transition, determine a transition-specific compensation function to apply to a feedforward input signal of the signal path that is combined with the loop filter output.

Abstract: This disclosure relates to a signal generating circuit and an audio processing device. The circuit includes a switch module, a voltage producing module, and a signal generating module; the switch module is connected to the voltage producing module, including at least one control switch, and is used for receiving a frequency division signal. Based on the frequency division signal, the at least one control switch is turned on or turned off; the voltage producing module is separately connected to the switch module and the signal generating module and used for producing a first voltage and a second voltage. The at least one control switch controls the first voltage and the second voltage to change. The signal generating module is connected to the voltage producing module and used for generating a carrier signal with the same frequency as the frequency division signal according to the received first and second voltages.

Abstract: A hybrid class-H/predictive class-G switching amplifier architecture and techniques for amplifying a signal (e.g., an audio signal) using such an architecture. One example method of amplification generally includes delaying an input signal to generate a delayed version of the input signal, amplifying the delayed version of the input signal with an amplifier powered by a boost converter, and selectively controlling the boost converter to operate in at least one of a predictive class-G mode or a class-H mode, based on a magnitude of the input signal.

Abstract: An apparatus comprises circuitry configured to generate a predicted error signal by applying to a digital signal a distortion model characterized by parameters configured to model circuit component mismatches in a digital-to-analog converter (DAC), circuitry configured to generate a pre-compensated digital signal using the digital signal and the predicted error signal, and circuitry configured to provide the pre-compensated digital signal to the DAC for conversion into an analog signal.

Abstract: A class-D amplifying system includes: a first digital-to-analog converter (DAC), a class-D amplifier circuit and a second DAC. The first DAC generates an analog input signal according to a digital input signal. The class-D amplifier circuit generates an output signal according to the analog input signal in a pulse width modulation (PWM) manner. The second DAC generates a common mode (CM) adjustment current for adjusting a CM voltage of the analog input signal according to one or more of the following parameters: (1) the CM voltage of the analog input signal; and/or (2) a driving power. A power stage circuit of the class-D amplifier circuit is powered by the driving power. The second DAC determines which parameter the CM adjustment current is correlated to according to: (A) A level state of the output signal; and/or (B) A level state of a PWM signal of the class-D amplifier circuit.

Abstract: A Class D power amplification modulation system for self-adaptive adjustment of an audio signal is provided, including an amplification circuit module, a pulse width modulation (PWM) circuit module connected to the amplification circuit module, a frequency detection circuit module, a carrier generator module connected to the frequency detection circuit module, an amplitude detection circuit module, a direct current (DC) potential adjustment module connected to the amplitude detection circuit module, and a drive circuit module. A method, a device, a processor, and a computer-readable storage medium are also provided. The characteristics of the circuit in the signal time domain and frequency are improved by simultaneously controlling the amplitude and the frequency of the audio signal, to minimize power consumption of signals with different amplitudes and frequencies, and to improve EMI performance, or to balance the circuit power consumption and EMI characteristics.

Abstract: Disclosed herein are devices and methods of using a mobile or wearable device for the acquisition and spatial filtering of ECG signals from an electrode array. One variation of a mobile or wearable device comprises an array of electrodes, one or more reference electrodes, and a controller in communication with the electrodes. In one example, the one or more reference electrodes are located on a wrist-worn device (e.g., a watch), and the electrode array is located on an accessory device that may be contacted with a fingertip. One variation of a spatial filtering method comprises identifying the electrodes that have high levels of noise and excluding the ECG signals from those electrodes from further analyses. In another variation, a method of spatial filtering comprises identifying electrodes with low levels of noise and including only the ECG signals from those electrodes in further analyses.

Abstract: A switched mode amplifier system may include a switched mode amplifier having an amplifier input coupled to an output of an analog integrator and an amplifier output and include a calibration system. The calibration system may be configured to force the input of the analog integrator to a fixed known input value, force the amplifier output to a fixed known duty cycle, measure an analog signal generated at the output of the analog integrator in response to forcing the input of the analog integrator to the fixed value, determine an offset of the switched mode amplifier system based on the analog signal, and correct for the offset.

Abstract: An isolator of embodiments includes a ?? analog-digital converter configured to convert an analog signal into a digital signal of one bit and transmit the digital signal of one bit as normal data, a time direction multiplexing circuit configured to perform time direction multiplexing of alternately performing conversion of the normal data into a digital differential signal and transmission of the digital differential signal, and transmission of a special signal different from the normal data, and an insulated transmission circuit configured to transmit the digital differential signal and the special signal transmitted from the time direction multiplexing circuit via an insulating layer.

Abstract: Numerous examples of a precision programming apparatus are disclosed for precisely and quickly depositing the correct amount of charge on the floating gate of a non-volatile memory cell within a vector-by-matrix multiplication (VMM) array in an artificial neural network. In one example, a neuron output circuit for providing a current to program as a weight value in a selected memory cell in a vector-by-matrix multiplication array is disclosed, the neuron output circuit comprising a first adjustable current source to generate a scaled current in response to a neuron current to implement a positive weight, and a second adjustable current source to generate a scaled current in response to a neuron current to implement a negative weight.

Abstract: A switching amplifier system with a power supply, a pulse modulator configured to modulate an input signal into a pulse width modulation signal, a switching stage configured to generate an amplified output signal, and an error feedback signal configured to correct errors in the amplified output signal, where the input signal is comprised of at least one of an analog signal and a digital signal. A method of signal amplification comprising generating, by a pulse width modulator, a pulse width modulation signal, combining, by a switching stage, the input signal and the pulse width modulation signal to form an amplified output signal, and generating, by the switching stage, an error feedback signal, where the error feedback signal is configured to correct errors in the amplified output signal, and where the input signal is comprised of at least one of an analog signal and a digital signal.

Abstract: An audio amplifier employs an idle mode to reduce power consumption and improve efficiency of the amplifier. The audio amplifier comprises a modulator configured to receive an analog input signal. The modulator is operable to convert the analog input signal to differential first and second quantized signals, each having a common mode duty cycle. The modulator causes the common mode duty cycle of each of the first and second quantized signals to be shifted when the level of the analog input signal is below a threshold level so that the common mode duty cycle is one of greater than or less than fifty percent (50%). The amplifier further includes a power stage that receives the first and second quantized signals and generates corresponding first and second output signals configured to drive a load, wherein the first and second output signals switched between a supply voltage and a second voltage based on the respective first and second quantized signals.

Abstract: A monolithic component includes a field-effect power transistor and at least one first Schottky diode inside and on top of a gallium nitride substrate.

Abstract: Systems and methods for calibrating a wireless power transmitter is described. A wireless power transmitter can include a controller and an amplifier module. The amplifier module can include an amplifier configured to amplify a voltage converted from a current proportional to power consumed by a wireless power transmitter, and a circuit connected to the amplifier. The circuit can be configured to receive a control signal from the controller. The circuit can be further configured to perform time division multiplexing on an output of the amplifier according to the control signal. A time division multiplexed output of the amplifier can include calibration data of the amplifier. The amplifier can be configured to output the time division multiplexed output to the controller.

Abstract: A digital audio playback circuit includes a noise shaping circuit configured to receive an input digital audio signal, and a digital to analog converter (DAC) configured to convert the input digital audio signal to a pre-amplified output analog audio signal according to a gain ramp defined by a gain control signal. A muting circuit is configured to compare input digital audio signal to a threshold and assert a mute control signal when the input digital audio signal is below the threshold. An analog gain control ramp circuit is configured to generate the gain control signal in response to the mute control signal to cause the gain ramp to ramp down. An amplifier is configured to amplify the pre-amplified output analog audio signal for playback by an audio playback device.

Abstract: Class D amplifier circuitry comprising: input buffer circuitry configured to receive a first digital input signal modulated according to a first modulation scheme in which the digital input signal can take a first plurality N of discrete signal levels; analog modulator circuitry configured to generate an analog modulated signal based on an analog output signal output by the input buffer circuitry; and quantizer circuitry configured to generate an output signal based on the analog modulated signal, wherein the output signal is modulated according to a second modulation scheme in which the output signal can take a second plurality M of discrete signal levels, wherein the second plurality M is greater than the first plurality N.

Abstract: A tool for performing diagnostics on a fire detection system includes an induction coil which includes two halves that may be selectively opened and closed to surround a wire in the system and sense current through the wire. A diagnostic module and a conduit provide communication of data of the sensed current between the induction coil and the diagnostic module. The diagnostic module is configured to decode the data to interpret communications sent through the wire.

Abstract: A level shift transistor of a first conductivity type configured to level shift a signal from a primary side circuit to a secondary side circuit between the primary side circuit having a primary side reference potential as reference and the secondary side circuit having a secondary side reference potential independent from the primary side reference potential as reference, a diode connected in a forward direction between a first main electrode of the level shift transistor and the secondary side circuit, a capacitor connected in parallel to the diode, and an inverter configured to invert the signal are provided. A control electrode of the level shift transistor is connected to a primary side power supply of the primary side circuit, and a second main electrode thereof is connected to an output of the inverter. The inverter operates between the primary side reference potential and the primary side power supply.

Abstract: An amplifier system may include at least one input source, a converter configured to provide voltage rails to an amplifier, the voltage rails including a first voltage rail and a second voltage rail, a MOSFET arranged at a secondary side of the system at the first voltage rail, a second MOSFET arranged at the first voltage rail, a third MOSFET arranged at the second voltage rail, a fourth MOSFET arranged at the second voltage rail; and, a first capacitor arranged at the first voltage rail and a second capacitor arranged at the second voltage rail, the first and forth MOSFETS are configured to operate simultaneously with one another and the second and third MOSFETs are configured to operate simultaneously with one another and opposite of the first and fourth MOSFETs so as to allow synchronous rectification so that the first and second capacitors reciprocally and mutually exclusively charge and discharge.