H03F3/217

Audio power source with improved efficiency

Example embodiments provide a device that includes a power transformer with a first output voltage terminal providing a first voltage and a second output voltage terminal providing a second voltage, a voltage regulator coupled to one or more of the first output voltage terminal and the second output voltage terminal, and a power storage element that stores power supplied by the second output voltage, and the first output voltage terminal supplies power to a remote entity until a load power requirement of the remote entity exceeds a threshold power level at which time the power storage element is used to provide power from the second output voltage terminal to the remote entity.

Minimizing phase mismatch and offset sensitivity in a dual-path system

A method of determining a phase misalignment between a first signal generated from a first signal path and a second signal generated from a second signal path may include obtaining multiple samples of the first signal proximate to when the first signal crosses zero wherein the first signal can be approximated as linear; obtaining multiple samples of the second signal proximate to when the second signal crosses zero wherein the first signal can be approximated as linear; based on the multiple samples of the first signal, approximating a first time at which the first signal crosses zero; based on the multiple samples of the second signal, approximating a second time at which the second signal crosses zero; and determining the phase misalignment between the first signal and the second signal based on a difference between the first time and the second time.

ADC CIRCUITRY

This application relates to ADC circuitry. An ADC circuit (200) has first and second conversion paths (201a, 201b) for converting analogue signals to digital and is operable in first and second modes. In the first mode, the first and second conversion paths are connected to respective first and second input nodes (202a, 202b) to receive and convert full scale first and second analogue input signals (Ain1, Ain2) to separate digital outputs (Dout1, Dout2). In the second mode, the first and second conversion paths are both connected to the first input node (202a), to convert the first analogue input signal (Ain1) to respective first and second digital signals, and the first and second conversion paths are configured for processing different signal levels of the first analogue input signal. A selector (207) select the first digital signal or the second digital to be output as an output signal based on an indication of amplitude of the first analogue input signal.

Differential circuit calibration apparatus and method
11112481 · 2021-09-07 · ·

An apparatus for calibrating a differential circuit that includes a differential integrator having an input, a gain, and an output connected to a comparator. The differential integrator output is chargeable to a threshold prior to an integration period. The differential integrator integrates the input during the integration period such that the differential integrator output goes toward zero from the threshold. The comparator detects the output of the differential integrator reaching zero. The apparatus includes a closed-loop gain trim circuit to perform a coarse calibration to adjust and set the gain of the differential integrator and a reference generator that generates the threshold to which the differential integrator output is pre-charged. The reference generator is trimmable during a fine calibration to adjust and set the threshold to correct for residual gain error in the differential circuit remaining after the coarse calibration is performed.

Differential circuit calibration apparatus and method
11112481 · 2021-09-07 · ·

An apparatus for calibrating a differential circuit that includes a differential integrator having an input, a gain, and an output connected to a comparator. The differential integrator output is chargeable to a threshold prior to an integration period. The differential integrator integrates the input during the integration period such that the differential integrator output goes toward zero from the threshold. The comparator detects the output of the differential integrator reaching zero. The apparatus includes a closed-loop gain trim circuit to perform a coarse calibration to adjust and set the gain of the differential integrator and a reference generator that generates the threshold to which the differential integrator output is pre-charged. The reference generator is trimmable during a fine calibration to adjust and set the threshold to correct for residual gain error in the differential circuit remaining after the coarse calibration is performed.

Driving Circuit with Energy Recycle Capability
20210175798 · 2021-06-10 ·

A driving circuit is disclosed. The driving circuit includes a charging circuit, coupled between a voltage source and a load, configured to form a first current from the voltage source to the load; and a discharging circuit, coupled between the voltage source and the load, configured to form a second current from the load back to the voltage source.

Method of Driving Circuit with Energy Recycle Capability
20210175864 · 2021-06-10 ·

A method applied in a driving circuit is disclosed. The driving circuit is coupled between a voltage source and a load and configured to drive the load. The method includes: forming, by the driving circuit, a first current from the voltage source to the load; and forming, by the driving circuit, a second current from the load back to the voltage source.

DEGLITCHING CIRCUIT AND METHOD IN A CLASS-D AMPLIFIER
20210203293 · 2021-07-01 ·

In an embodiment, a class-D amplifier includes an input terminal configured to receive an input signal; a comparator having an input coupled to the input terminal; a deglitching circuit having an input coupled to an output of the comparator; and a driving circuit having an input coupled to an output of the deglitching circuit. The deglitching circuit includes a logic circuit coupled between the input of the deglitching circuit and the output of the deglitching circuit. The logic circuit is configured to receive a clock signal having the same frequency as the switching frequency of the class-D amplifier.

SINE-WAVE GENERATION USING PULSED D-CLASS AMPLIFIER
20210281216 · 2021-09-09 ·

A sine wave generator includes a resonator circuit, a control circuit and a pulse generator. The resonator circuit is configured to receive energy pulses and to generate a resonator sinusoidal signal responsively to the energy pulses. The control circuit is configured to estimate a signal measure of the resonator sinusoidal signal, or of a signal derived from the resonator sinusoidal signal. The pulse generator is configured to generate the energy pulses responsive to the signal measure estimated by the control circuit, and to drive the resonator circuit with the energy pulses.

SINE-WAVE GENERATION USING PULSED D-CLASS AMPLIFIER
20210281216 · 2021-09-09 ·

A sine wave generator includes a resonator circuit, a control circuit and a pulse generator. The resonator circuit is configured to receive energy pulses and to generate a resonator sinusoidal signal responsively to the energy pulses. The control circuit is configured to estimate a signal measure of the resonator sinusoidal signal, or of a signal derived from the resonator sinusoidal signal. The pulse generator is configured to generate the energy pulses responsive to the signal measure estimated by the control circuit, and to drive the resonator circuit with the energy pulses.