| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 330131000 | Control of bias on separate gain control electrode | 18 |
| 20100109770 | RECONFIGURABLE POWER AMPLIFIER AND USE OF SUCH AMPLIFIER FOR MAKING A MULTI-STANDARD AMPLIFICATION STAGE FOR MOBILE PHONE COMMUNICATIONS - A reconfigurable power amplifier includes at least one amplification circuit (E | 05-06-2010 |
| 20100308909 | PA GAIN STATE SWITCHING BASED ON WAVEFORM LINEARITY - Techniques for optimizing the power consumption of existing low cost multi-gain state power amplifiers (PA) to increase the talk time of wireless communication devices are described. In an exemplary embodiment a device, such as a baseband processor, operates to set a multistage PA having at least two gain states for amplifying a transmit signal to a lowest power consuming gain state. The device calculates a transition power level as a function of an identified maximum power reduction (MPR) value and switches the PA to a higher gain state from a lower gain state when a transmission power level is higher than the calculated transition power level. | 12-09-2010 |
| 20100321108 | METHOD AND APPARATUS FOR CONTROLLING HIGH POWER AMPLIFIER IN COMMUNICATION SYSTEM - An apparatus and method for controlling a high power amplifier in a communication system are provided. The apparatus includes a Radio Frequency (RF) power detection unit for detecting an intensity of an RF input signal, a high power amplifier controller for determining a control signal, which indicates a voltage value of a drain bias to be provided to at least one drain node from among drain nodes of a drive amplifier and a main amplifier included in the high power amplifier, according to the detected intensity, a Direct Current (DC) voltage supplying unit for generating a DC voltage corresponding to the determined control signal, a drain bias connection unit for providing the generated DC voltage to said at least one drain node from among the drain nodes of the drive amplifier and the main amplifier, and the drive amplifier and the main amplifier for amplifying the RF input signal according to the provided DC voltage. | 12-23-2010 |
| 20110043282 | RF POWER AMPLIFIER SYSTEM WITH IMPEDANCE MODULATION - A power amplifier controller circuit controls an adjustable impedance matching network at the output of a power amplifier to vary its load line to improve the efficiency of the RF PA. The PA controller circuit comprises an amplitude control loop that determines an amplitude correction signal. The amplitude loop is configured to control or correct for distortion from the adjustable matching network based upon the amplitude correction signal. | 02-24-2011 |
| 20110068867 | SYSTEM AND METHOD FOR INTERPOLATING DIGITALLY-CONTROLLED AMPLIFIER GAIN - A digitally-controlled analog gain circuit supports a plurality of gain settings in which gain changes are made from a first setting to a new setting in response to a clocking signal. Large changes in gain are interpolated in small gain steps or increments. The clocking signal can be generated by an oscillator, or as a sequence of pulses output by a zero crossing detector. The gain circuit can apply positive gain to the signal. Alternatively, the gain circuit can apply a negative gain (attenuation) to the signal. The clocking signal can be provided in a pseudo-randomized manner to minimize unwanted signal effects such as discernable sound transients. | 03-24-2011 |
| 20110090008 | POWER AMPLIFICATION APPARATUS AND POWER AMPLIFICATION METHOD - Disclosed is a power amplifier apparatus including: an amplifier amplifying an input modulated signal; a control signal generator receiving an amplitude component of the input modulated signal and generating a control signal; and a power combiner performing ON/OFF control of a switching element based on the control signal to control conduction and non-conduction of a current supplied from a second power supply. In the power combiner, a power of a pulsed form when the current from the second power supply is conductive is transferred in a direction of a first power supply, using a transformer. A difference power obtained by subtracting a constant value from a first power supply voltage when the amplitude of the input modulated signal is smaller than that of a reference signal is supplied from the power combiner to the amplifier, as a power supply thereof (FIG. | 04-21-2011 |
| 20120105151 | TRANSMISSION CIRCUIT AND TRANSMISSION METHOD - Provided is a transmission circuit capable of compensating a variation in output power caused due to a temperature change or an individual variability when the operation mode is switched without an increase in the size of the transmission circuit which switches the operation mode between a linear operation mode and a nonlinear operation mode, and capable of suppressing the deterioration of the quality of a transmission signal. In the transmission circuit, a gain setting section ( | 05-03-2012 |
| 20120133432 | HIGH EFFICIENCY AUDIO AMPLIFIER - An audio amplifier circuit is described which comprises an operational amplifier. The operational amplifier receives an audio input signal and provides an output suitable for connecting a headphone, or a loudspeaker. A step-up converter is provided which supplies the operational amplifier. The audio amplifier is configured to operate in one of multiple operating modes, each of which uses a distinct supply voltage Vcc of the operational amplifier in the audio amplifier. Comparators are used to compare the output voltage of the operational amplifier with a first reference voltage to raise the supply voltage of the operational amplifier, if clipping is imminent. A second comparator is used to compare the output voltage of the operational amplifier with a second reference voltage, indicating that the supply voltage of the operational amplifier can be lowered without the risk of clipping. | 05-31-2012 |
| 20120200354 | APPARATUS AND METHODS FOR ENVELOPE TRACKING CALIBRATION - Apparatus and methods for envelope tracking calibration are provided. In one embodiment, a method of calibrating an envelope tracker having an envelope shaping table generated at a desired gain compression of a power amplifier is provided. The method includes generating a supply voltage for the power amplifier using the envelope tracker, operating the supply voltage of the power amplifier at a first voltage level associated with substantially no gain compression of the power amplifier, and measuring an output power of the power amplifier at the first voltage level. The method further includes decreasing a voltage level of the supply voltage one or more times and measuring the output power at each voltage level, determining a second voltage level of the power amplifier associated with a gain compression equal to about that of the desired gain compression, and calibrating the envelope tracker based on the determination. | 08-09-2012 |
| 20120249240 | System and method for effectively implementing a front end for a transimpedance amplifier - An apparatus for implementing a front end circuit for a transimpedance amplifier includes a front end core that receives an input signal from a photo diode. The front end core responsively generates a balanced output signal to downstream devices. A power supply provides a supply voltage to the front end circuit. In accordance with the present invention, a current source is located between the supply voltage the front end core to thereby isolate the front end core from disturbances on the power supply. This biasing arrangement advantageously provides an improved power supply rejection ratio for the front end circuit. | 10-04-2012 |
| 20120293255 | AMPLIFIER, TRANSMISSION DEVICE, AND AMPLIFIER CONTROL METHOD - An amplifier includes an envelope detection unit that detects an envelope of a transmission signal; a comparing unit that compares a voltage of the envelope with a reference voltage; a selecting unit that selects, in accordance with a comparison result obtained by the comparing unit, an amplifying element that amplifies the transmission signal from among a plurality of amplifying elements each having different operating power; a voltage control unit that controls, in accordance with the envelope, a voltage that is used to amplify the transmission signal in the amplifying element that is selected by the selecting unit; a current measuring unit that measures a current of a power supply that supplies the voltage that is controlled by the voltage control unit; and a reference voltage control unit that controls the reference voltage such that the current measured by the current measuring unit decreases. | 11-22-2012 |
| 20120306572 | METHOD OF POWER AMPLIFIER CALIBRATION FOR AN ENVELOPE TRACKING SYSTEM - A method for power amplifier (PA) calibration for an envelope tracking system of a wireless device is disclosed. The method involves measuring an output power of a PA that is a part under test (PUT) at a predetermined input power. Another step includes calculating a gain equal to the output power of the PA divided by the predetermined input power. A next step involves calculating a gain correction by subtracting the calculated gain from a desired gain. Other steps include determining an expected supply voltage for the PA at the desired gain using the gain correction applied to a nominal curve of gain versus PA supply voltage, and then storing the expected supply voltage for the PA versus input power in memory. | 12-06-2012 |
| 20120313702 | Dual Rail Out-Phased Envelope Tracking Modulator - A drain modulator circuit for operation with a radio frequency (RF) amplifier, includes a pair of AC signal sources each of the AC signal sources having an output at which an AC signal is provided. The drain modulator circuit further includes a pair of tapped delay elements, each of which is configured to receive an AC signal from a respective one of the AC signal sources and a control element coupled to provide one or more control signals to the pair of tapped delay elements such that the tapped delay elements provide a selected instantaneous differential voltage to the RF amplifier. | 12-13-2012 |
| 20120326782 | AUTOMATIC GAIN CONTROL CIRCUIT - In an automatic gain control circuit, a peak detection circuit detects and outputs the peak voltage of an output signal from a variable gain circuit. An average value detection/output amplitude setting circuit detects the average value voltage of an output signal from the variable gain circuit, and outputs a calculated voltage. An amplification circuit controls the gain of the variable gain circuit by amplifying the difference between the output voltages of the peak detection circuit and average value detection/output amplitude setting circuit. The number of base-emitter junctions of transistors on a path in the peak detection circuit from input ports which receive output signals from the variable gain circuit to an output port which outputs a voltage to the amplification circuit is equal to the number of base-emitter junctions of transistors on a path in the average value detection/output amplitude setting circuit. | 12-27-2012 |
| 20130099861 | METHOD AND APPARATUS FOR CONTROLLING TRANSMIT SIGNAL OF RADIO FREQUENCY POWER AMPLIFIER - A method and an apparatus for controlling a transmit signal of a radio frequency power amplifier are provided. The method includes: adjusting a power supply voltage of the power amplifier to an efficiency point power supply voltage under designated transmit power; querying correspondence between an input voltage and transmit power at each power level under the efficiency point power supply voltage; and adjusting, according to the correspondence, an input voltage to an input voltage corresponding to the designated transmit power. The embodiments of the present invention, the power amplifier is enabled to work at an optimum efficiency point while the transmit power of the power amplifier is under control, which improves efficiency of the power amplifier. | 04-25-2013 |
| 20130328626 | BIAS CONTROL CIRCUIT - The problem to be solved is to alleviate the distortion characteristic of an amplifier and to prevent the drop in gain with respect to a low-level high-frequency signal. A bias control circuit ( | 12-12-2013 |
| 20140015604 | Amplifier Circuit, Method and Mobile Communication Device - An amplifier circuit includes a gain controller, a first amplifier, and a second amplifier which is coupled in series to the first amplifier, the second amplifier comprising a plurality of amplifying units. The gain controller is configured to receive a desired gain value and provide, based on the received desired gain value, a gain adjust signal to the first amplifier, and activate, based on the received desired gain value, a certain combination of amplifying units of the plurality of amplifying units of the second amplifier, such that a combined gain of the first amplifier and the active amplifying units of the second amplifier corresponds to the received desired gain value | 01-16-2014 |
| 20140210550 | REVERSE CURRENT PREVENTION - Techniques for preventing reverse current in applications wherein a tracking supply voltage is placed in parallel with a switching power stage. The tracking supply voltage may be boosted to a level higher than a battery supply voltage using, e.g., a boost converter. In an aspect, a negative current detection block is provided to detect negative current flow from the boosted tracking supply voltage to the battery supply voltage. A high-side switch of the switching power stage may be disabled in response to detecting the negative current. To prevent false tripping, the tracking supply voltage may be further compared with the battery supply voltage, and a latch may be provided to further control the high-side switch. | 07-31-2014 |
