Class / Patent application number | Description | Number of patent applications / Date published |
330136000 | Bias control signal from input of amplifier | 16 |
20080238543 | Digital Amplifier with Analogue Error Correction Circuit - Digital amplifier for amplifying a digital input signal, comprising a digital modulator for converting the digital input signal into an amplitude-discrete and temporally analogue signal, comprising an analogue error correction circuit which modulates the pulse widths of the amplitude-discrete and temporally analogue signal in dependence on an analogue error signal, comprising a power switching stage, the input of which receives the signal modulated by the error correction circuit and which delivers the modulated signal amplified at an output and comprising an analogue feedback circuit which, in dependence on the output signal of the digital modulator and on the output signal of the power switching stage, generates the analogue error signal for adjusting the analogue error correction circuit. | 10-02-2008 |
20080278231 | AMPLIFIER - An object of the present invention is, in a high-frequency amplifier using a semiconductor device as an amplifying device, to achieve a high efficiency by controlling input/output matching circuits so that they are always optimized, when a bias voltage applied to the semiconductor device is controlled to correspond to an envelope of a signal. The bias voltage that is applied to the semiconductor device for amplification is changed to corresponding to the envelope of the signal using a bias control circuit, control voltages for controlling impedance of input/output matching circuits are created from the bias voltage, and the bias voltage and the control voltages that are used to control the impedance of the input/output matching circuits of semiconductor device | 11-13-2008 |
20080284510 | ERROR DRIVEN RF POWER AMPLIFIER CONTROL WITH INCREASED EFFICIENCY - A power amplifier controller for adjusting a supply voltage to a power amplifier. The power amplifier controller adjusts the supply voltage so that distortion in an RF output signal corresponds to a predetermined limit. An amplitude error signal is generated by the power amplifier controller which represents a difference between an RF output signal and an attenuated RF output signal. The AC components of the amplitude error signal are processed to generate a deviation signal that represents the distortion in the RF output signal. The supply voltage to the power amplifier is increased when the deviation signal exceeds a distortion level control signal, and decreased when the deviation signal drops below the distortion level control signal. | 11-20-2008 |
20080297246 | Polar amplifier - An amplifier circuit receives a phase modulated signal at an input node. The power supply terminal of the amplifier circuit is modulated in accordance with an amplitude envelope signal. The voltage on the power supply terminal is modulated using one or more linear regulators depending on the magnitude of the envelope signal. | 12-04-2008 |
20090140805 | Voltage Regulator For Biasing Current-To-Voltage Amplifiers - A voltage regulator, comprising an analog amplifier, a noise filter and a signal compensator, is disclosed. The noise filter for receives a first signal containing alternating current (AC) noise in which the noise filter substantially filters the AC noise from the first signal to thereby produce a second signal. The voltage regulator regulates the second signal to thereby generate a third signal therefrom. The third signal is substantially noise-free and is provided as a biasing voltage to the analog amplifier. The first signal is further provided to for amplification by the analog amplifier based on amplification characteristics of the analog amplifier and the amplification characteristics of the analog amplifier is determined by the biasing voltage provided to the analog amplifier. | 06-04-2009 |
20090184764 | POWER SUPPLY PROVIDING ULTRAFAST MODULATION OF OUTPUT VOLTAGE - A circuit for use with a power amplifier that amplifies an input signal. The circuit may comprise an amplitude correction circuit and an open-loop switching regulator. The amplitude correction circuit may be configured to generate a corrected envelope signal from an input envelope signal that represents an envelope of the input signal. The open-loop switching regulator may be connected to the amplitude correction circuit and may be for powering the power amplifier based on the corrected envelope signal. According to various embodiments, the corrected envelope signal generated by the amplitude correction circuit is a function of the input envelope signal and an error voltage of the open-loop switching regulator. | 07-23-2009 |
20090189690 | FEED-FORWARD AUTOMATIC-GAIN CONTROL AMPLIFIER (FFAGCA) FOR BIOMEDICAL APPLICATIONS AND AN ASSOCIATED METHOD - The present invention is a feed-forward automatic-gain control amplifier (FFAGCA) for biomedical applications and associated method, the FFAGCA comprises a detector, a controller, a variable gain amplifier (VGA), an input and an output. The associated method to process various kinds of biomedical signals with the FFAGCA comprises acts of adjusting gain setting with control path and simultaneously a signal amplification with signal path. | 07-30-2009 |
20090195308 | AUTOMATIC GAIN CONTROL CIRCUIT - An automatic gain control circuit includes a first voltage dividing resistor, a filter circuit, a switch circuit, and an amplifying circuit. The first voltage dividing resistor divides a voltage of the automatic gain control circuit using an internal impedance of the audio device to produce a divided DC voltage, wherein the first voltage dividing resistor is connected between a first power source and an output of the audio device. The filter circuit filters audio signals outputted from the audio device to produce filtered audio signals, and wherein the filter circuit receives the divided DC voltage, wherein the filter circuit is connected to the output of the audio device. The switch circuit outputs controlling signals according to the divided DC voltage from the filter circuit. The amplifying circuit amplifies the filtered audio signals according to the controlling signals. An electronic device using the automatic gain control circuit is also provided. | 08-06-2009 |
20100019844 | HIGH EFFICIENCY PRECISION AMPLIFIER - A high efficiency precision amplifier which comprises a linear amplifier stage, a class D amplifier stage and a set of switches is provided. Both amplifier stages receive the same input signal. The load is driven by the output of the linear amplifier stage. The set of switches connect the output of the class D amplifier stage to either of the positive and negative supply terminals of the linear amplifier stage and the other of the positive and negative supply terminals of the linear amplifier stage to a negative or positive supply, depending on the polarity of the signal being amplified. | 01-28-2010 |
20100219888 | AMPLIFIER CIRCUIT - An amplifier circuit comprises an input, for receiving an input signal to be amplified; a preamplifier, for amplifying the input signal based on a variable gain; a power amplifier for amplifying the signal output from the preamplifier, and a variable voltage power supply for supplying one or more supply voltages to the power amplifier. The supply voltages are adjusted based on the variable gain or the input digital signal. According to other aspects of the invention, a power supply of an amplifier circuit is clocked using a clock signal, whereby the clock signal has a frequency that varies in accordance with a volume signal or an input signal. | 09-02-2010 |
20120025907 | POWER AMPLIFIER - There is provided a power amplifier capable of supplying variable bias to an amplifier circuit by accurately transferring the envelope components of an input signal during the supply of active bias power to the amplifier circuit. The power amplifier includes: an envelope detector detecting an envelope of an input signal; a bias power generator including at least one P-type MOSFET and one N-type MOSFET connected to each other in an inverter manner between a driving power terminal supplying driving power having a preset voltage level and a reference bias power terminal supplying preset reference bias power to generate bias power varied according to detection results from the envelope detector; and an amplifier amplifying the input signal according to the bias power level from the bias power generator. | 02-02-2012 |
20120025908 | AUTOMATIC GAIN CONTROL - An automatic gain controller is disclosed. The AGC includes an input for monitoring a signal associated with an amplifier and a gain control circuit for controlling the gain of the amplifier in response to the monitored signal, wherein the gain control circuit is adapted to control the gain of the amplifier in accordance with a gain control function having continuously variable attack and release time constants, both of which depend on the amplitude of the monitored signal. | 02-02-2012 |
20120105152 | Joint optimisation of supply and bias modulation - There is disclosed a technique for controlling at least one amplification stage, comprising: selecting a linearity objective for the amplification stage; in dependence on an input signal to said amplification stage, determining a combination of supply input and bias input for the amplification stage in order to meet said linearity objective; and in dependence on there being more than one combination of supply input and bias input for meeting the linearity objective, selecting the combination that optimises a further system performance objective for the amplification stage. The further system performance objective may be one or more of: an efficiency objective; an envelope signal bandwidth objective; or a robustness to production tolerance objective. | 05-03-2012 |
20130141159 | INTEGRATED CIRCUIT, WIRELESS COMMUNICATION UNIT AND METHOD FOR A DIFFERENTIAL INTERFACE FOR AN ENVELOPE TRACKING SIGNAL - An integrated circuit for providing a differential interface for an envelope tracking signal is described. The integrated circuit includes a subtraction module having a first input for receiving a digital envelope tracking signal and a second input for receiving a second signal, wherein the subtraction module is arranged to subtract the second signal from the digital envelope tracking signal and produce an envelope tracking signal with a reduced average direct current (DC) component; a digital-to-analog converter (DAC) arranged to receive the envelope tracking signal with the reduced average DC component and produce a differential analog version thereof; and a modulator operably coupled to a differential output of the DAC, wherein the modulator comprises a DC input point arranged to insert a DC component into the differential analog version of the envelope tracking signal. | 06-06-2013 |
20140097893 | TRANSMITTER AND SIGNAL PROCESSING METHOD - The switching frequency in an envelope amplifier is set below that of a transmission RF signal. A transmitter according to the present invention includes a transmission amplifier ( | 04-10-2014 |
20140132345 | Power Control - An amplification stage comprising: an input scaling block for scaling an input signal based on an input scaling factor to generate a scaled version of the input signal; a power amplifier for receiving the scaled version of the input signal and for generating an amplified version of said signal; an envelope detector for generating a signal representing the envelope of the input signal; an envelope scaling block for scaling the envelope signal based on an envelope scaling factor to generate a scaled version of the envelope signal; a non-linear mapping block for generating a voltage representative of the supply voltage based on the scaled envelope signal; a modulator for generating a power supply voltage for the amplifier based on the voltage generated by the non-linear mapping block; and a power control block for maintaining a linear relationship between the envelope scaling factor and the input scaling factor. | 05-15-2014 |