H03M3/50

Electrical circuit

An electrical circuit includes a signal processing chain and a controller. The signal processing chain includes an integrator configured to integrate an input signal over an integration time. The controller is connected to a signal output of the signal processing chain to receive and evaluate an output signal of the signal processing chain. The controller is further configured to adapt the integration time based on the output signal.

ESTIMATING VOLTAGE ON SPEAKER TERMINALS DRIVEN BY A CLASS-D AMPLIFIER
20170272045 · 2017-09-21 ·

A system includes an audio amplifier, a duty cycle detector, a channel equalizer, and a sample-and-hold circuit. The audio amplifier is configured to amplify an analog audio signal to produce an amplified audio signal. The duty cycle detector is configured to generate a saturation detect signal at a first state upon detection that the amplified audio signal produced by the audio amplifier is clipped. The channel equalizer is configured to generate an initial estimate of a speaker terminal voltage. The sample-and-hold circuit is configured to sample and hold the initial estimate of the speaker terminal voltage as a final estimate of the speaker voltage when the saturation detect signal is in the first state.

Envelope dependent output stage scalability
09768800 · 2017-09-19 · ·

An apparatus comprises a digital to analog converter (DAC) circuit configured to receive a time-varying a digital input signal and convert the digital input signal to an analog output signal, an output amplifier circuit operatively coupled to the output of the DAC circuit, a peak detector circuit operatively coupled to the input the DAC and configured to produce a signal envelope of the digital input signal, and logic circuitry. The logic circuitry is operatively coupled to the peak detector circuit and is configured to detect when the signal envelope satisfies a specified threshold value; and to adjust a drive capability of an output amplifier circuit of the DAC circuit according to the signal envelope.

DIGITAL MODULATOR, COMMUNICATION DEVICE, AND DIGITAL MODULATOR CONTROL METHOD
20220239544 · 2022-07-28 · ·

A digital modulator according to the present disclosure includes a polar converter that generates a phase signal and an amplitude signal from a baseband signal, an RF phase signal generator that generates an RF phase signal on the basis of the phase signal, a rectangulating unit that generates a rectangular RF phase signal by converting the RF phase signal into a rectangular shape, a time interleaver that time interleaves the amplitude signal and outputs first and second time interleaved signals, a ΔΣ modulator that ΔΣ modulates the first and second time interleaved signals on the basis of the rectangular RF phase signal and outputs first and second ΔΣ modulated signals, and a selector that selects and outputs one of the first and second ΔΣ modulated signals on the basis of the rectangular RF phase signal.

RF-DAC DIGITAL SIGNAL MODULATION

Radar frequency range signals (e.g., 1 to 100 gigahertz) are often generated by upconverting a reference frequency to a transmission frequency, and a received signal may be downconverted to analyze information encoded on the transmission via modulation. Modulation may be achieved via a fractional frequency divider in a phase-locked loop, but fractional spurs may reduce the signal-to-noise ratio. Additionally, the ramp slope may vary due to phase-locked loop momentum. Instead, a clock generator may generate clock signals for a digital front end comprising a digital signal modulator that generates modulated digital values comprising quadrature representations of a radar modulation signal, which are encoded by a radiofrequency digital-to-analog converter (RF-DAC). The RF-DAC analog signal may be upconverted to a radar frequency and transmitted. A receiver may receive, downconvert, and analyze a reflection of the radar transmission, e.g., to perform range detection based on a frequency ramp encoded by the radar transmission.

POWER SUPPLY AND INSPECTION APPARATUS
20220178988 · 2022-06-09 ·

A power supply for supplying a power to a heating mechanism used for heating a measurement target that emits a measurement signal includes an input device configured to output an input signal that reflects a control signal in a differentiable periodic waveform having a frequency of 1 kHz or less. The power supply includes a switching amplifier configured to amplify the input signal from the input device and output the amplified signal.

SYSTEMS FOR AND METHODS OF FRACTIONAL FREQUENCY DIVISION

Systems and methods provide a fractional signal from a delta sigma modulator to a summer, a combination of an integer value and the fractional signal to a divider, and a divided clock signal from the divider in response to the combination and the input clock signal. The systems and methods also delay the divided clock signal in response to a truncation phase error and gain calibration factor from a calibration unit to provide an output clock signal having equal periods.

DEVICE AND METHOD FOR SUPPLYING POWER TO AN ULTRASOUND TRANSDUCER

A device for supplying an ultrasonic transducer including a power interface configured to provide an analog power signal, called supply signal, to the ultrasonic transducer, and further including a delta-sigma modulator configured to produce a delta-sigma modulator of a sinusoidal signal, called drive signal, and provide a digital signal, called control signal, to control said power interface. Also an ultrasonic device powered by such a supply device, an ultrasonic head including such ultrasonic devices and an ultrasonic system including such an ultrasonic head.

Transmission system, transmitting apparatus, receiving apparatus, and program

In a transmission system of an audio signal etc., circuit enlargement is suppressed and deterioration of transmitting signal is reduced. A transmission system including a transmitting apparatus including a first delta-sigma modulator outputting first multi-bit delta-sigma modulated signals of three or more bits and a first code modulator code-modulating first signals of two or more bits located in bit positions higher than a predetermined bit position of the first multi-bit delta-sigma modulated signals based on at least part of a second signal located in one or more bit positions not higher than the predetermined bit position and outputting a plurality of modulated signals; a transmission path transmitting the second signal and the plurality of modulated signals; and a receiving apparatus including a first demodulator demodulating the plurality of the received modulated signals based on at least part of the received second signal is provided.

System and methods for virtualizing delta sigma digitization

A method for virtually performing delta-sigma digitization is provided. The method is performed on a series of digital samples output from a communication stack of a communication network. The method includes steps of obtaining a delta-sigma digitization sampling frequency for the output series of digital samples, calculating an oversampling ratio for the output series of digital samples, interpolating the output series of digital samples at a rate equivalent to the oversampling ratio, and quantizing the interpolated series of digital samples to plurality of discrete predetermined levels.