Method and apparatus for amplifying audio signal

Methods and apparatus for variable solid state-to-tube rectification in an amplifier

Amplification apparatus

Digital to-analog converter

Amplifier circuit and integrated circuit therefor

Low distortion cascode amplifier circuit

Audio signal amplifier circuit

Charging circuit and amplifier

Dynamic constant power amplifier

Dynamic switchable mode dual bridge power amplifier

Method and control circuit for controlling pulse width modulation

Headphone amplifier circuit

Class-D amplifier with dual feedback loop

Output circuit for audio codec chip

Amplifier circuit

Sound volume adjusting apparatus

Modulated Triangular Wave Amplifier

Electronic volume circuit

Noise cancellation for microphone-speaker combinations using combined speaker amplifier and reference sensing

Audio signal controller

High level capable audio amplification circuit

ADC chopping transconductor having two pairs of cascode transistors

Quiet power up and power down of closed loop digital PWM modulators

DOUBLE INTEGRAL METHOD OF POWERING UP OR DOWN A SPEAKER

Amplifier stage

Preamplifier circuit for a microelectromechanical capacitive acoustic transducer

Audio processing circuit and preamplifier circuit

Method and apparatus for controlling power supply of audio amplifier

ΔΣ modulation digital-analog converter, digital signal processing method, and AV device

Circuit and method for reducing popping sound

AMPLIFIER CIRCUIT

Audio compensation method and audio apparatus with class AB power amplifier

Amplifier circuit, electronic device, method for configuring an amplifier circuit

Digital signal converter

Hybrid feedback controlled oscillation modulator and switching power amplifier system

TWO-CHANNEL AMPLIFIER WITH COMMON SIGNAL

Amplifier circuit audio circuit and electronic device

Amplifier circuit of capacitor microphone

PWM AMPLIFIER

Motional feedback system

Class D amplifier circuit

Audio circuit

Amplifier circuit

Bi-directional and adjustable current source

Public-address system

Amplifier circuitry

Pulse width modulation circuit and class-D amplifier comprising the PWM circuit

Electronic signal processor

AUDIO DEVICE, AV SYSTEM HAVING THE AUDIO DEVICE, AND METHOD TO CONTROL THE AUDIO DEVICE

Push-pull linear hybrid class H amplifier

Method of and circuit for adjusting frequency of a driving signal of electronic horn by means of capacitor

Adaptive signal-feed-forward circuit and method for reducing amplifier power without signal distortion

Chopping technique for continuous time sigma-delta ADCs without Q-noise folding

Power management controller for drivers

Audio out unit

Amplifier circuit and method therefor

Acoustic apparatus and method of controlling an acoustic apparatus

Amplification circuit and method therefor

Magnetic coupler device and magnetically coupled isolator

Wireless electronic device with multimode audio amplifier

METHOD AND APPARATUS FOR OPERATION SEQUENCING OF AUDIO AMPLIFIERS

Feedback amplifier and audio system thererof

TRACK AND HOLD CIRCUITS FOR AUDIO SYSTEMS AND OEPRATIONAL METHODS THEREOF

Sigma delta class D power amplifier and method thereof

Amplifier device

HIGH-VOLTAGE OUTPUT AMPLIFIER FOR AUDIO SYSTEMS

Headphone amplifier circuit

Error correction system for a class-D power stage

Method and electronic device for driving a capacitance electro-acoustic transducer

AUDIO OUTPUT DEVICE

Minimum pulse generation in a class-D amplifier

STAGED LINEAR CONVERSION METHOD

Digital adaptive feedforward harmonic distortion compensation for digitally controlled power stage

Multi-Channel Amplifier

Sound reproducing system with superimposed digital signal

Amplification circuit and hearing aid

Bias balancing circuit

Audio device and audio input/output method

Class-D amplifier

Amplifier circuit

Data processing system for clipping correction

Folded cascode operational amplifier having improved phase margin

Method and apparatus for output amplifier protection

Audio amplifier

Anti-pop circuits and methods for audio amplifiers using variable resistors

Amplifier current drive reversal

SYSTEM AND METHOD OF CONTROLLING POWER CONSUMPTION IN RESPONSE TO VOLUME CONTROL

Digital microphone

Miniature speaker device and television set

Method and apparatus for power converter for class D audio power amplifiers

Dynamic contoured-sound/subwoofer-synthesis audio system

Amplification circuit for driving a diffuser

Audio amplifier with timing circuit to power down bias control and amplifying circuits in sequence

AUDIO AMPLIFIER

AUDIO AMPLIFIER

Bypassing amplification

Precision triangle waveform generator

ACOUSTIC SPEAKER SYSTEM WITH STRONG BASS CAPABILITY

Thermal protection of electro dynamic transducers used in loudspeaker systems

Audio Power Amplifier with Feedback-Shifting Technology

Pop noise eliminating circuit that disables an audio output device when turning the device on

Noise filter and noise-filter-incorporated amplifier circuit

Reduction of power consumption and EMI of a switching amplifier

Class D audio amplifier

Output circuit of vacuum-tube amplifier

System and method of reducing power consumption for audio playback

Output DC offset protection for class D amplifiers

Differential audio amplifier

DC self-biased vacuum tube differential amplifier with grid-to-cathode over-voltage protection

Pop noise suppression apparatus and audio output system utilizing the same

Preset circuit of audio power amplifier

Muting control device, muting control method, and muting control program

System and method of reducing click and pop noise in audio playback devices

Signal generating apparatus and related method

HEADPHONE AMPLIFIER CIRCUIT

Over-current sensing during narrow gate drive operation of class D output stages

Micro-electro-mechanical systems (MEMS) capacitive sensing circuit

Electric device

Class D amplifier

Systems and methods for sample rate conversion

Switching amplifiers

Combining an audio power amplifier and a power converter in a single device

Low cost high performance power amplifier utilizing two-stage-included local negative feedback with feedback-shifting technology

Audio amplifier

Automatic power source configuration

Amplifier having an output protection, in particular operational amplifier for audio application

Audio power conversion system

Audio output device and method

LOW DISTORTION CLASS-D AMPLIFIER

Computer installed stereo PA amplifier card

High-voltage transconductance circuit

Output limiting circuit, class D power amplifier and audio equipment

Digital audio amplifiers, electronic systems, and methods

Load testing circuit

Signal amplifying apparatus, amplification system, and signal amplification method

Circuit for inhibiting over-current in power amplifier

Class D amplifier with increased efficiency

Class D amplifier circuit

A/V amplifier and method for driving the same

Integrated circuit device and audio system

Amplifier with configurable DC-coupled or AC-coupled output

Power amplification device

Digital audio signal amplifier

CIRCUIT AND METHOD FOR ELIMINATING SPEAKER CRACKLE DURING TURNING ON OR OFF POWER AMPLIFIER

Amplifier circuit having an output transistor for driving a complex load

Power amplifier with noise shaping function

Pulse width modulator using interpolator

Multi-mode audio amplifiers

Apparatus and method for asymmetric charge pump for an audio amplifier

Electronic signal processor

Electronic signal processor

Audio system for improving a signal to noise ratio

Solid state tesla coil suit

System and method for forming and controlling electric arcs

Electronic signal processor

Output circuits with class D amplifier

System and method for controlling an electromagnetic field generator

Systems and methods for correcting errors resulting from component mismatch in a feedback path

Capacitive load driving device

Single supply direct drive amplifier

Filterless class-D speaker driver with less switching

Communication method for vacuum tube replacement devices

APPARATUS AND METHOD FOR CONTROLLING VOLUME

Audio playing systems

Power-MOSFETs with improved efficiency for multi-channel class-D audio amplifiers and packaging thereof

Digital audio amplifier and digital audio amplifying method therefor

Digital amplifier with analogue error correction circuit

Signal processing circuit comprising an attenuating unit, a detecting unit, and an attenuation rate setting unit

Audio Amplifier with Reduced Noises

Microphone amplification arrangement and integrated circuit therefor

Vacuum tube replacement device, circuit and system

System and method for minimizing DC offset in outputs of audio power amplifiers

Driver amplifier circuit having reduced DC bias

Audio power amplifier apparatus

Audio system with power-on/off noise suppression and audio amplifier thereof

Power amplifier

Methods and apparatus to detect impedance at an amplifier output

Modulated triangular wave amplifier

Multi-stage amplifier with multiple sets of fixed and variable voltage rails

Electron turbulence damping circuit for a complimentary-symmetry amplification unit

Low distortion switching amplifier circuits and methods

Foot pedal apparatus to provide variable output for guitar

PROTECTION AND AUTOMATIC RECOVERY CIRCUIT SYSTEM

Low distortion switching amplifier circuits and methods

Audio amplifier circuit and electronic apparatus including the same

Deep sub-micron MOS preamplifier with thick-oxide input stage transistor

Low distortion class-D amplifier

AUDIO SIGNAL OUTPUT CIRCUIT CAPABLE OF DECREASING POP NOISE

Apparatus and muting circuit

Digital amplifying apparatus with noise reduction

Control circuit and method for a switching amplifier

Circuit arrangement for adjusting the output power and/or the frequency response of a power amplifier for a hearing aid device

Audio amplifier system

Three-stage amplifier

Speaker

Class-D driving method for stereo load

Noise reduction system and method for audio switching amplifier

Switching amplifier circuits and methods

Circuit arrangement for suppression of switching noises

Circuit and method of reducing pop-up noise in a digital amplifier

Class ad audio amplifier

Audio amplifier capable of performing self-oscillation

Compensated gain control device

Amplifier apparatus and method

Current-regulated, bootstrapped-biased, high to low impedance signal-buffer/output-driver for audio electronics

Audio control method and audio processing system

CONTROLLING AUDIO OUTPUT OF A MOBILE TERMINAL

Amplifier apparatus and method

Reduction of voltage spikes in switching half-bridge stages

Amplifier apparatus and method

Methods and system for detecting DC output levels in an audio system

DEVICE FOR PREVENTING POP NOISE IN AN AUDIO OUTPUT APPARATUS AND METHOD THEREFOR

Energy-efficient consumer device audio power output stage

Sigma-delta based Class D audio or servo amplifier with load noise shaping

Output circuit of vacuum-tube amplifier

Differential input Class D amplifier

Protected digital audio driver

MULTI-CHANNEL, MULTI-POWER CLASS D AMPLIFIER WITH REGULATED POWER SUPPLY

Class-D audio amplifier with half-swing pulse-width-modulation

Method and apparatus for normalizing sound playback loudness

Amplifier circuits, methods of starting and stopping amplifier circuits

Amplifier circuit, semiconductor device and electronic apparatus

Single-ended screen-regulated cathode-follower output stage for high-fidelity music amplifier

Dual Mode Audio Amplifier

USB HUB WITH A USB POWERED SPEAKER

Power amplifier

Ripple digital amplifier system

Method of and apparatus to generate pulse width modulated signal from sampled digital signal by chaotic modulation

Expanded performance and functions for vacuum tube replacement devices

High Linearity Modulation System and Modulation Method

Signal Output Circuit, Audio Signal Output Apparatus Using The Same, And Electronic Device

Digital amplifier

Apparatus and method for controlling temperature of electronic apparatus

Automatic gain control circuit and signal reproducing device

Noise free implementation of PWM modulator combined with gate driver stage in a single die

RIAA CORRECTION OF AUDIO SIGNAL WITH USE OF TRANSFORMER

Amplifier circuit of BTL system

Audio power amplifier IC and audio system provided with the same

Digital amplifier and television receiving apparatus

Single supply direct drive amplifier

Semiconductor device for microphone applications

Audio amplifier and methods for use therewith

Differential amplifier and methods for use therewith

System and method for minimizing DC offset in outputs of audio power amplifiers

Amplifier

Self-oscillating switching amplifier

PWM feedback/feed-forward protection

Systems and methods for minimizing delay in a control path

Systems and methods for pulse width modulating asymmetric signal levels

Systems and methods for improving performance in a digital amplifier by adding an ultrasonic signal to an input audio signal

Apparatus and method for importing content including plural pieces of usage constraint information

Circuit for suppressing audio noise

Digital feedback to improve the sound reproduction of an electro-dynamic loudspeaker

Switching amplifier

Distortion compensation

Overcurrent detection circuit and switching circuit

CLASS D AMPLIFIER WITH START-UP CLICK NOISE ELIMINATION

Quiet power up and power down of a digital audio amplifier

Multi-channel noise reduction system with direct instrument tracking

Method and system for equalization of a replacement load

Electronic apparatus having audio output units

Output coupling capacitor free audio power amplifier dynamically configured for speakers and headphones with excellent click and pop performance

Capacitive load driving circuit, electrostatic transducer, method of setting circuit constant, ultrasonic speaker, display device, and directional acoustic system

Audio signal output control device that suppresses pop sound

Audio output driver and methods for use therewith

Power conversion system

Precision triangle waveform generator

Amplifier Arrangement and Distributed Audio System

Method and apparatus to control output power of a digital power amplifier optimized to a headphone and a portable audio player having the same

Output offset protection for power amplifier

Low-distortion tri-state switching amplifier

Low-distortion tri-state switching amplifier

Amplifier circuit

Audio amplifier

Input/output signals preserver circuit of amplification circuits

SPEAKER PROTECTION CIRCUIT

Apparatus and method to control audio volume in D class amplifier

Low distortion class-D amplifier using carrier reference signal symmetry modulation

Charging circuit and control method and integrated circuit utilizing the same

Method of estimating an intersection between at least two continuous signal representations

Protection circuit of digital amplifier

Output stage for a hearing aid and method of driving output stage

Indicators for vacuum tube replacement devices

Class AB-D audio power amplifier

Update system for an audio amplifier

Automute detection in digital audio amplifiers

Noise sensitive volume control device, audio device and noise sensitive volume control method

System and method for employing variable magnetic flux bias in an amplifier

Modulated triangular wave amplifier

Switching amplifier

Low-distortion tri-state switching amplifier

Pulse-width modulation circuits of self-oscillation type and pulse-width modulation methods

Serial audio output driver circuits and methods

Multi-channel, multi-power class D amplifier with regulated power supply

Broadband microwave amplifier

Method and topology to switch an output stage in a class ab audio amplifier for wireless applications

D-class audio power amplifier and method thereof

Amplifier apparatus

Method and system for equalization of a replacement load

Pwm generator