Skyworks Solutions, Inc.

Mark R Peting

Miles Reuben Thompson

Wai Laing Lee

Deepika Kumari

Taehwan Oh

Amit Kumar

Evan Michael Albright

Donald Allen Pearce

Eric Thomas King

David Lamb

Spencer David Leuenberger

Dale A Beyer

In some embodiments, an audio driver includes an audio amplifier configured to operate in a high output resistance (HOR) mode with an HOR driver or a zero output resistance (ZOR) mode with a ZOR driver, The audio amplifier includes an output node coupled to both of the HOR driver and the ZOR driver, such that the output node is subject to an effect of the ZOR driver in a disabled state when the audio amplifier is operating in the HOR mode. The audio driver further includes a control system configured to correct for the effect of the disabled ZOR driver by adjusting an input signal.

Output capacitance distortion correction for audio amplifiers

This disclosure relates to a system for mitigating distortion in a signal, including a plurality of bit-cells, a calculation circuit configured to determine a bit-cell population that is available to be activated for a given clock cycle, a dynamic element matching network configured to activate a subset of bit-cells of the bit-cell population, and a controller configured to control a pattern of activation of the subset of bit-cells of the bit-cell population.

Continuously variable dynamic element matching network

A method and system of compensating for component mismatch are disclosed. An example system comprises an amplifier including a current ratio measurement engine (CRME) and a modulator (DSM). The CRME is configured to obtain measurements for each possible configuration of an amplifier circuit and to pass these measurements to a processor for analysis. In the example system, the measurements are obtained by driving a bias current through two or more circuit elements and measuring the ratio in current between the two or more circuit elements, which is representative of the relative mismatch between the two or more components. The DSM is configured to receive adjustment parameters from the processor and to tune the amplifier circuit according to the adjustment parameters to thereby improve the performance of the amplifier.

Method and system for component mismatch compensation

This disclosure relates to a system for mitigating distortion in a signal, including a first calculation circuit configured to determine a bit-cell population available to be activated of a plurality of bit-cells based on a signal strength of an input signal, a second calculation circuit configured to determine a number of bit-cells to be activated based on the signal strength of the input signal, the number of bit-cells to be activated being less than or equal to the bit-cell population, a variable-width dynamic element matching network ('variable DEM') configured to activate a first subset of bit-cells of the bit-cell population based on the number of bit-cells to be activated, and one or more fixed-width dynamic element matching networks (“fixed DEMs”) configured to activate a second subset of bit-cells of the bit-cell population based on the number of bit-cells to be activated.

Noise shaped drive and population balanced network

A class-D amplifier having an output driver with a first, second, and third driver, the output driver having a first output coupled to the first and third drivers, a second output coupled to the second driver; a sensing resistor coupled in series between the first driver and the first output; and a pulse width modulation (PWM) controller coupled to the inputs of the drivers and configured to receive an audio input signal; control a PWM generator to generate a first pulse signal and a second pulse signal based on the audio input signal and a power supply input; determine a voltage drop across the sensing resistor; and, responsive to the voltage drop being greater than a threshold, sequence control of the first pulse signal to the first driver and switch a voltage at the first driver to an increased voltage based on the voltage drop.

Class-D amplifier for reducing audio distortion

A switching audio amplifier and method of operation. The switching audio amplifier comprises a voltage supply selector coupling a power supply input to a first power supply voltage; a switching circuit generating a drive signal for a loudspeaker by modulating the power supply input based on a modulation signal; a pulse generator receiving an audio input signal and outputting the modulation signal based on the audio input signal and the voltage of the power supply input; and a supply voltage monitor. The supply voltage monitor is configured to increase the voltage of the power supply input by causing the voltage supply selector to couple the power supply input to a second power supply voltage responsive to the modulation signal exceeding the first threshold, and the supply voltage monitor preventing the voltage supply selector from reducing the voltage of the power supply input for a first time period.

Switching audio amplifier with improved voltage supply control

In some embodiments, a low voltage system can include a capacitor between an output node of an amplifier and ground, with the output node connectable to a load, and the amplifier configured to operate with a series of pulses. The low voltage system can further include a monitoring circuit configured to monitor a voltage at the capacitor against a desired low voltage value, and a control system configured to generate the series of pulses for the amplifier, and to control charging and discharging of the capacitor based on an output of the monitoring circuit to regulate the voltage at the output node at approximately the desired low voltage value.

Low voltage system for audio amplifiers

In some embodiments, a calibration circuit for an audio amplification system can include a tone generator configured to provide a tone having a frequency to an input path of an audio amplifier, such that an input signal provided to the audio amplifier includes the tone, a a first sampling circuit configured to sample an output signal at an output node of the audio amplifier, and a second sampling circuit configured to sample the input signal at an input node of the audio amplifier. The calibration circuit can further include a gain adjustment circuit configured to generate a correction signal based on the sampled output signal and the sampled input signal to correct for a gain variation of the audio amplifier.

Gain calibration for audio amplifiers

Amplifying a signal includes outputting an output signal from a Class D amplifier configured to operate as a current driver to a load, such as a loudspeaker, the output of the Class D amplifier controlled by a feedback loop, and, in the feedback loop: performing analog filtering using an active analog filter on an error signal that is based on the output of the Class D amplifier and a reference signal, digitizing a filtered output of the analog filter to produce a sequence of digital values, performing digital filtering on the sequence of digital values to produce a sequence of filtered digital values, and generating a pulse signal to control the output of the Class D amplifier based on the sequence of filtered digital values. The digital filter reduces a destabilizing effect of the loudspeaker's inductance. Associated circuits, systems, modules and electronic devices are disclosed.

Growing community of inventors

Yamhill, OR, United States of America

Mark R Peting