Match Document Document Title
7622988 Chopper-stabilized instrumentation amplifier for impedance measurement  
This disclosure describes a chopper stabilized instrumentation amplifier. The amplifier is configured to achieve stable measurements at low frequency with very low power consumption. The...
7619467 Modulated triangular wave amplifier  
The invention is a power amplifier circuit for providing a signal acceptable for use in audio amplifiers or similar applications without requiring a stable power supply free from fluctuations. An...
7616053 Power amplifier circuit and method for envelope modulation of high frequency signal  
A power amplifier circuit includes: a transformer receiving a first signal and generating a transformed signal from the first signal; and a transistor receiving a second signal having a direct...
7612608 Sigma-delta based Class D audio or servo amplifier with load noise shaping  
An amplifier capable of driving an analog load is provided. The amplifier can be constructed and arranged to operate as at least one circuit selected from the group consisting of a class D...
7609110 Filterless class-D speaker driver with less switching  
Methods for designing a filterless class-D amplifier and driver are described herein. In the exemplary embodiment, a feedback loop is used to stabilize the filterless class-D amplifier. A pulse...
7605653 Sigma-delta based class D audio power amplifier with high power efficiency  
An amplifier capable of driving an analog load is provided. The amplifier comprises a sigma delta modulator (SDM), a pulse processing circuit, an output stage, and a feedback loop. The SDM produces...
7602245 Method, apparatus and system for reducing DC coupling capacitance at switching amplifier  
A digital amplifier, a reference voltage generator for reducing a DC component of an amplified pulse width modulated signal of a digital amplifier, and a method of reducing a DC component of an...
7589590 Circuit architecture having differential processing for use in half bridges and full bridges and methods therefore  
Circuit architecture is disclosed that includes one or more half bridges, the one or more half bridges including signal processing circuitry including first and second inputs and one or more...
7586370 Class D amplifier  
The invention is directed to a class D amplifier. According to the class D amplifier, sound data applied to an input terminal is supplied through a compensation circuit to a PWM circuit, from which...
7586369 Pulse modulation type electric power amplifier  
A pulse modulation type electric power amplifier includes a pulse modulator that receives as input a clock and an input signal, and converts the input signal to a pulse train, an output control...
7583138 System and method for controlling an error amplifier between control mode changes  
A system and a method are disclosed for controlling an error amplifier between control mode changes. An error amplifier comprises a first stage that comprises a first current source and a second...
7583137 Power supply compensation  
The invention relates to an amplifier comprising amplification means (AM) comprising an input and an output, said amplification means (AM) comprising a switching output stage delivering at least...
7580532 Multi-channel pulse width modulation apparatus  
Disclosed are multi-channel PWM (Pulse Width Modulation) apparatuses and methods for modulating PCM-based multi-channel audio signals read from an optical medium into PWM-based multi-channel audio...
7579910 Low distortion switching amplifier circuits and methods  
Embodiments of the present invention include switching amplifier circuits and methods. In one embodiment, the present invention includes an low distortion method of driving a switching amplifier...
7579908 Digital audio amplifiers, electronic systems, and methods  
An embodiment of an electronic system includes a digital audio amplifier having a continuous time modulator adapted to generate a difference signal between an audio bitstream and a feedback signal,...
7579907 Switching amplifier  
A switching amplifier of the invention boasts of an enhanced SN ratio in its output and an increased amplitude limit value in its input signal. The switching amplifier has a quantized signal...
7576606 Digital PWM amplifier having a low delay corrector  
Systems and methods for performance improvements in digital switching amplifiers using a low delay corrector. In one embodiment, a digital pulse width modulation (PWM) amplifier includes a signal...
7576605 Low power output stage  
Power consumption of an output stage such as a class-D output stage may depend on the amplitude and the activity of the signal being output. Here, control signals may be generated to independently...
7576604 All-digital class-D audio amplifier  
An all-digital class-D audio amplifier and method of digitizing an analog signal comprises a pulse-width modulation (PWM) wave generator for generating a PWM wave; an interpolator for receiving an...
7573328 Power amplifier  
A power amplifier is disclosed. In one embodiment, the power amplifier is a Class-D Amplifier having a differential pulse width modulator is disclosed. The differential pulse width modulator has an...
7570711 Quadrature LINC transmission method and apparatus  
A quadrature LINC transmission system processes a baseband input signal for transmission as a linearly amplified RF signal. An in-phase LINC element processes an in-phase baseband signal into an...
7570118 Thermal overload protection circuit and method for protecting switching power amplifier circuits  
A thermal overload protection circuit and method for protecting switching power amplifier circuits provides protection against latch-up and other failures due to energy returned from an inductive...
7564397 High slew rate amplifier, analog-to-digital converter using same, CMOS imager using the analog-to-digital converter and related methods  
An amplifier, which may be used in a pipelined analog-to-digital converter, includes a first amplifier stage driving a second amplifier stage. At least one compensation capacitor is coupled to...
7557744 PWM driver and class D amplifier using same  
The objective of the invention is to provide a class D amplifier that can reduce aliasing noise. The class D amplifier has D/A converter 10 that operates at the first sampling frequency, and PWM...
7557650 Electronic signal generator with modulated cyclic ratio, compensated for variations in its power supply voltage  
A generator capable of supplying one or more output signals with a modulated cyclic ratio includes one or more formatting circuits each processing one input signal and one or more class D...
7554409 Over-current protection circuit and method for protecting switching power amplifier circuits  
An over-current protection circuit protection circuit and method for protecting switching power amplifier circuits provides protection against latch-up and other failures due to energy returned...
7554391 Amplifier having a virtual ground and method thereof  
An amplifier comprises first, second, and third modulators. The first modulator includes an input for receiving a first input signal, and an output for providing a first modulated output signal...
7554390 Method and system for transitioning between operation states in an output system  
A closed loop amplifier system comprising a modulator that provides a pulse-width modulated (PWM) output signal based on an input signal, the modulator having a variable closed loop transfer...
7551028 Signal generators for current-mode three-level digital amplifiers  
Apparatus having corresponding methods comprise: a first fixed current source to produce a first fixed current; a second fixed current source to produce a second fixed current; a first adjustable...
7551022 Power supply compensation  
The invention relates to an amplifier comprising amplification means (AM) comprising an input and an output, said amplification means (AM) comprising a switching output stage delivering at least...
7548110 Power amplifier and method for reducing common noise of power amplifier  
A power amplifier including a delta-sigma modulation module, a differential programmable dead-time-control module, and an output stage module is provided. The delta-sigma modulation module...
7545207 Control circuit and method for a switching amplifier  
In a control circuit and method for a high efficiency and low EMI switching amplifier, an input signal is compared with a reference signal to generate a comparison signal, and a control signal is...
7541869 Feedback amplifier  
A feedback architecture for a PWM switching audio amplifier is, capable of compensating the effects of the demodulation filter through at least two feedback paths of the voltage applied to a load...
7541865 EER high frequency amplifier  
An EER high frequency amplifier wherein the dynamic range of the gain can be widened by performing a predetermined control of a device in a high frequency amplifying part and thereby enhancing the...
7541864 Power amplifier and pulse-width modulated amplifier  
The invention relates to a power amplifier having a phase amplification path with a phase amplification stage within said phase amplification path. Here the phase amplification stage receives a...
7538607 Class D amplifier  
The invention is directed to a class D amplifier. According to the class D amplifier, sound data applied to an input terminal is supplied through a compensation circuit to a PWM circuit, from which...
7535296 Class-E radio frequency power amplifier with feedback control  
A Class-E power amplifier includes a choke and a switch connected in series between a source of a supply voltage and circuit ground and connected to an inductively coupled coil. An output node of...
7528651 Noise free implementation of PWM modulator combined with gate driver stage in a single die  
An integrated noise isolation circuit on a single silicon substrate die having a structural arrangement that minimizes noise. The integrated circuit including a noise sensitive circuit including an...
7528650 Multi-channel digital amplifier, signal processing method thereof, and audio reproducing system having the same  
A multi-channel digital amplifier system to generate a pulse width modulation (PWM) signal having a different switching frequency in each channel, and a signal processing method thereof. The...
7525377 Method for controlling a linear power amplifier  
A linear power amplifier filters an instantaneous input signal to generate a filtered input signal, combines the instantaneous input signal and filtered input signal to generate a modified drain...
7518450 Digital amplifier  
Recently, the use of class D audio amplifiers has become more and more widespread. In contrast to the generally employed class AB linear amplification technology, class D allows for improved...
7518445 Systems, methods, and apparatuses for linear envelope elimination and restoration transmitters  
Systems, methods, and apparatuses are provided for linear envelope elimination and restoration transmitters that are based on the polar modulation operating in conjunction with the orthogonal...
7518444 PWM feedback/feed-forward protection  
Systems and methods for improving the stability of feedback and/or feed-forward subsystems in digital amplifiers. One embodiment comprises a digital pulse width modulation (PWM) controller. The...
7518443 Amplifier circuit and method for reducing voltage and current noise  
An amplifier circuit with current noise reduction employs first and second variable impedance devices between a signal source and an amplifier. A modulation frequency generator establishes a...
7518442 Circuit and method for suppressing switching and supply-related errors in a PWM power stage by instantaneous per-pulse feedback  
A class D amplifier is provided. The class D amplifier includes a modulator and a class D power stage. The modulator provides a PWM output signal to the class D power stage. For each pulse of the...
7518441 Signal processor for use with a power amplifier in a wireless circuit  
A signal processor has an input terminal and an output terminal for use in a wireless transmitter, for generating a radio frequency signal suitable for transmission, either with or without further...
7515885 Communications signal amplifiers having independent power control and amplitude modulation  
The present invention, generally speaking, provides methods and apparatus for producing an amplitude modulated communications signal, in which a constant-envelope carrier signal is modified in...
7515646 Method and apparatus for reducing EMI emissions for data signals traveling over a data pathway  
An improved data signal electromagnetic emissions system is provided for sending data signals over one or more data pathways. An original data signal is encoded into a set of sideband frequencies...
7509102 DAC based switching power amplifier  
A power amplifier for use in a transmitter includes a first transistor having an input, a first node and a second node, a second transistor having an input, a first node and a second node and a...
7501886 Low distortion class-D amplifier  
An amplifier that receives an input signal and outputs an amplified output signal includes an integration stage, a comparison stage, and a full bridge circuit. The integration stage is be used for...