Abstract: A radio frequency (RF) power amplifier system adjusts the supply voltage provided to a power amplifier (PA) adaptively, responsive to the measured or estimated power of the RF output signal of the PA. The RF PA system includes a power amplifier (PA) which receives and amplifies an RF input signal to generate an RF output signal at a level suitable for transmission to an antenna. A PA supply voltage controller generates a supply voltage control signal, which is used to control the supply voltage to the final stage of the PA. The supply voltage control signal is generated responsive to the measured or estimated power of the PA RF output signal, and also may be responsive to a parameter indicative of impedance mismatch experienced at the PA output. By controlling this supply voltage to the RF PA, the efficiency of the PA is improved.

Abstract: A SPDT or SPMT switch may include a transformer having a primary winding and a secondary winding, where a first end of the secondary winding is connected to a single pole port, where a first end of the primary winding is connected to a first throw port; a first switch having a first end and a second end, where the first end is connected to ground; and a second switch, where a second end of the secondary winding is connected to both a second end of the first switch and a first end of the second switch, where a second end of the second switch is connected to a second throw port, where the first switch controls a first communication path between the single pole port and the first throw port, and where the second switch controls a second communication path between the second throw port and the single pole port.

Abstract: An amplifier is operable in push-pull mode, single-ended mode, or a composite mode that is an intermediate between single-ended and Push-pull modes. Moreover, at least one output device may be configured to operate using a high performance AC servo loop that functions the output device as a current source. Still further, a control input driver stage is provided that is capable of supplying sufficient AC current to overcome Miller capacitance induced roll off within the intended frequency spectrum of triode vacuum tubes. Additionally, methods are provided to substantially null or selectively introduce DC magnetic bias within the output transformer core. Still further, a solid state power supply stage provides substantial AC hum reduction during single-ended operation and simultaneously provides output voltage load regulation attributes similar to traditional vacuum tube rectifier circuits.

Abstract: An impedance transformer includes a first transmission line having a first impedance and provided over a first substrate having a first permittivity; a second transmission line and a third transmission line having an impedance lower than the first impedance and provided over a second substrate having a permittivity higher than the first permittivity, the second transmission line and the third transmission line being electrically coupled to the first transmission line; and a resistor coupled between the second transmission line and the third transmission line.

Abstract: Disclosed are an impedance matching circuit preventing the occurrence of inter-line interference by making currents at adjacent lines flow in the same direction, and a power amplifier having the same.

Abstract: There is provided a wireless apparatus having a shielding function for shielding signal interference between driving power from a power amplifier and a conductive wire of a coupler. The wireless apparatus having a shielding function, includes an amplifying unit receiving preset driving power and amplifying a radio frequency (RF) input signal according to a preset gain, an impedance matching unit including at least one coil, receiving the driving power from the amplifying unit, and matching the impedance of a path of a signal, amplified from the amplifying unit, through the coil, and a shielding unit eliminating signal interference between the coil and a transmission path of the driving power from the amplifying unit.

Abstract: A power amplifier system in accordance with an example embodiment can utilize a transformer having a primary winding inductively coupled to a secondary winding, where the primary winding includes a center tap between a first port and a second port, where the secondary winding includes a third port and a fourth port, where the primary winding receives a first output from a first amplifier, where the center tap receives a second output from a second amplifier.

Abstract: Embodiments of the invention may provide for power amplifier systems and methods. The systems and methods may include a power amplifier that generates a first differential output signal and a second differential output signal, a primary winding comprised of a plurality of primary segments, where a first end of each primary segment is connected to a first common input port and a second end of each primary segment is connected to a second common input port, where the first common input port is operative to receive the first differential output signal, and where the second common input port is operative to receive the second differential output signal, and a single secondary winding inductively coupled to the plurality of primary segments.

Abstract: Systems and methods may be provided for a power amplifier system. The systems and methods may include a plurality of power amplifiers, where each power amplifier includes at least one output port. The systems and methods may also include a plurality of primary windings each having a first number of turns, where each primary winding is connected to at least one output port of the plurality of power amplifiers, and a single secondary winding inductively coupled to the plurality of primary windings, where the secondary winding includes a second number of turns greater than the first number of turns.

Abstract: In accordance with one the present disclosure, systems and methods are disclosed that include transmitting a binary signal from a signal source into a switch where the switch is in series between the signal source and a first circuit element. In addition, the switch is operating substantially in a switched mode and creates a switched output signal and the switch is controlled by the binary signal. Also disclosed in this method is detecting a negative voltage in a signal from a second circuit element. In this method the first circuit element is in series between the second circuit element and the switch, and upon detecting the negative voltage from the second circuit element the first circuit element creates high impedance in the first circuit element.

Abstract: Methods to implement power control in a digital power amplifier are described.

Abstract: In a method and in an apparatus for transmission of energy and data, with a primary side, on which an amplifier is arranged, with a secondary side, on which a data source, e.g. a measuring sensor, is arranged, and with a plug-together assembly inductively coupling, galvanically completely isolated, the primary side and the secondary side, to minimize power losses and disturbing influences of fluctuating parameters, power from the plug-together assembly and from the amplifier, preferably a Class-E-amplifier, is controlled to a predeterminable, desired value. For this, a microcontroller taps the primary voltage on the primary winding and produces for the amplifier a controlled operating voltage as well as a controlled operating frequency, in order to keep the working point of the amplifier always in the optimal region.

Abstract: An amplifier is operable in push-pull mode, single-ended mode, or a composite mode that is an intermediate between single-ended and Push-pull modes. Moreover, at least one output device may be configured to operate using a high performance AC servo loop that functions the output device as a current source. Still further, a control input driver stage is provided that is capable of supplying sufficient AC current to overcome Miller capacitance induced roll off within the intended frequency spectrum of triode vacuum tubes. Additionally, methods are provided to substantially null or selectively introduce DC magnetic bias within the output transformer core. Still further, a solid state power supply stage provides substantial AC hum reduction during single-ended operation and simultaneously provides output voltage load regulation attributes similar to traditional vacuum tube rectifier circuits.

Abstract: A transformer and a structure thereof and a power amplifier are provided. The transformer includes a first inductor to a fourth inductor, a first capacitor, and a second capacitor. A first terminal of the first inductor receives a first signal. A first terminal of the second inductor is coupled to the first terminal of the first inductor. A first terminal of the third inductor receives a second signal, and a second terminal of the third inductor is coupled to a second terminal of the first inductor. A first terminal of the fourth inductor is coupled to the first terminal of the third inductor. The first capacitor is coupled between the first terminal of the first inductor and the first terminal of the third inductor. The second capacitor is coupled between a second terminal of the second inductor and a second terminal of the forth inductor.

Abstract: A differential amplifier is formed from a first single-ended amplifier circuit, a second single-ended amplifier circuit, and a four-port transformer circuit coupled to the first and second single-ended amplifier circuits to form the differential amplifier.

Abstract: In one embodiment, the present invention includes multiple gain stages to receive and amplify a differential input signal at different common mode voltages. The stages each may include a pair of linear NMOS gain transistors coupled to a primary coil of a given output transformer. One of the stages may include commonly coupled terminals coupled to a center tap of the primary coil of an output transformer of another stage, and a supply current provided to one of the stages is re-used for the other stage(s).

Abstract: In one embodiment, the present invention includes multiple gain stages and an output network coupled to the gain stages. Each of the gain stages can be independently controlled to amplify a radio frequency (RF) signal to an output power level for transmission from a mobile wireless device. When controlled to be inactive, at least one of the gain stages can be placed into a low impedance state.

Abstract: Systems and methods may be provided for a power amplifier system. The systems and methods may include a plurality of power amplifiers, where each power amplifier includes at least one output port. The systems and methods may also include a plurality of primary windings each having a first number of turns, where each primary winding is connected to at least one output port of the plurality of power amplifiers, and a single secondary winding inductively coupled to the plurality of primary windings, where the secondary winding includes a second number of turns greater than the first number of turns.

Abstract: A transformer and a structure thereof and a power amplifier are provided. The transformer includes a first inductor to a fourth inductor, a first capacitor, and a second capacitor. A first terminal of the first inductor receives a first signal. A first terminal of the second inductor is coupled to the first terminal of the first inductor. A first terminal of the third inductor receives a second signal, and a second terminal of the third inductor is coupled to a second terminal of the first inductor. A first terminal of the fourth inductor is coupled to the first terminal of the third inductor. The first capacitor is coupled between the first terminal of the first inductor and the first terminal of the third inductor. The second capacitor is coupled between a second terminal of the second inductor and a second terminal of the forth inductor.

Abstract: A dual mode power amplifier output network is provided that includes a load switch and an auto transformer having a primary winding and a secondary winding. The load switch is connected to the secondary winding of the auto transformer.

Abstract: A differential amplifier is formed from a first single-ended amplifier circuit, a second single-ended amplifier circuit, and a four-port transformer circuit coupled to the first and second single-ended amplifier circuits to form the differential amplifier.

Abstract: In one embodiment, the present invention includes multiple gain stages and an output network coupled to the gain stages. Each of the gain stages can be independently controlled to amplify a radio frequency (RF) signal to an output power level for transmission from a mobile wireless device. When controlled to be inactive, at least one of the gain stages can be placed into a low impedance state.

Abstract: A differential amplifier is formed from a first single-ended amplifier circuit, a second single-ended amplifier circuit, and a four-port transformer circuit coupled to the first and second single-ended amplifier circuits to form the differential amplifier.

Abstract: Disclosed herein is a power amplifier using a power combiner, which is capable of minimizing power loss and improving efficiency of the power amplifier with a large output power, by combining powers generated by a plurality of power amplifiers used in a wireless communication system using a transmission line transformer.

Abstract: Embodiments of the invention may provide for power amplifier systems and methods. The systems and methods may include a power amplifier that generates a first differential output signal and a second differential output signal, a primary winding comprised of a plurality of primary segments, where a first end of each primary segment is connected to a first common input port and a second end of each primary segment is connected to a second common input port, where the first common input port is operative to receive the first differential output signal, and where the second common input port is operative to receive the second differential output signal, and a single secondary winding inductively coupled to the plurality of primary segments.

Abstract: The invention concerns an audio power amplifier apparatus capable of providing at low manufacturing cost extremely low non-linear distortion, even lower than ?120 dB, comprising a main power amplifying section the output of which is series connected to a secondary of a coupling transformer T1, in turn connected to the apparatus output, the apparatus being characterized in that the amplifying section provides an output signal Vma having a negative feed-back loop non-inverting gain, and in that it further comprises a cascade of one or more sections, the inputs of which are connected to the output of the input section and to the output of the amplifying section, and the output of which is constituted of a secondary winding of the transformer T1, the cascade being capable to very accurately extract the error signal Ve with respect to the amplified signal Vi from the signal at the output of the amplifying section and to to provide to its output an exact, but anti-phase, copy thereof in a predetermined very wide fr

Abstract: Embodiments of the invention may provide for power amplifier systems and methods. The systems and methods may include a power amplifier that generates a first differential output signal and a second differential output signal, a primary winding comprised of a plurality of primary segments, where a first end of each primary segment is connected to a first common input port and a second end of each primary segment is connected to a second common input port, where the first common input port is operative to receive the first differential output signal, and where the second common input port is operative to receive the second differential output signal, and a single secondary winding inductively coupled to the plurality of primary segments.

Abstract: An accurate linear equivalent of an analog signal may be produced across an isolation barrier by driving a primary transformer winding with a drive amplifier and compensation amplifier, where the compensation operational amplifier amplifies a difference between a signal produced on a sense winding of the transformer and a combination of the input analog signal and output of the drive amplifier. The system may be stabilized by a lead-lag network between the sense winding, input signal, and operational amplifier. The transformer may comprise an isolation barrier to isolate the input analog signal from a signal winding. The primary winding of the transformer, driven by the operational amplifier and driver amplifier circuit, may produce a linear equivalent of the input analog signal across the isolation barrier on a signal winding of the transformer.

Abstract: An accurate linear equivalent of an analog signal may be produced across an isolation barrier by driving a primary transformer winding with a drive amplifier and compensation amplifier, where the compensation operational amplifier amplifies a difference between a signal produced on a sense winding of the transformer and a combination of the input analog signal and output of the drive amplifier. The system may be stabilized by a lead-lag network between the sense winding, input signal, and operational amplifier. The transformer may comprise an isolation barrier to isolate the input analog signal from a signal winding. The primary winding of the transformer, driven by the operational amplifier and driver amplifier circuit, may produce a linear equivalent of the input analog signal across the isolation barrier on a signal winding of the transformer.

Abstract: An architecture for detecting amplifier power is provided. The architecture includes a voltage envelope detector that receives a voltage signal and generates a voltage envelope signal. A current envelope detector receives a current signal and generates a current envelope signal. A power amplifier level controller receives the greater of the voltage envelope signal and the current envelope signal, such as by connecting the output of the voltage envelope detector and the current envelope detector at a common point and conducting the high frequency current components to ground via a capacitor. A power amplifier level control signal is then generated based on the voltage drop across the capacitor.

Abstract: A power amplifier comprises a control signal generator providing a first and a second signal, a first amplifier comprising a first transistor and a first cascode transistor for the amplification of the first signal, a second amplifier comprising a second transistor and a second cascode transistor for the amplification of the second signal, and an output coupler which couples an output of the first amplifier and an output of the second amplifier to an output terminal of the amplifier arrangement.

Abstract: A differential amplifier is formed from a first single-ended amplifier circuit, a second single-ended amplifier circuit, and a four-port transformer circuit coupled to the first and second single-ended amplifier circuits to form the differential amplifier.

Abstract: Systems and methods may be provided for a power amplifier system. The systems and methods may include a plurality of power amplifiers, where each power amplifier includes at least one output port. The systems and methods may also include a plurality of primary windings each having a first number of turns, where each primary winding is connected to at least one output port of the plurality of power amplifiers, and a single secondary winding inductively coupled to the plurality of primary windings, where the secondary winding includes a second number of turns greater than the first number of turns.

Abstract: A high output power amplifier with change of voltage transformation ratio of a transformer is disclosed. The high output power amplifier using a transformer installed to output leads thereof, which can increase dynamic range and efficiency thereof as voltage transformation ratio of the transformer is adjusted and load resistance is adjusted so as not to generate signal distortion phenomenon and not to decrease its efficiency.

Abstract: A multi-level power amplifier architecture using a multi-tap transformer implemented on a single CMOS integrated circuit wireless communications device is described. By providing a multi-tap transformer for coupling a plurality of power amplifiers to a shared output impedance, such as an antenna, power transmission may be made at different levels while maintaining efficiency. With a multi-tap transformer having “N” taps featuring “N” different impedance levels, each tap may be connected to an amplifier cell which delivers power into the transformer at the tap for coupling to the output load. Any one of the “N” amplifier cells can be turned on at once along with any combination of the “N” amplifier cells.

Abstract: A system and method for employing variable magnetic flux bias in an amplifier. The amplifier system comprises an output transformer and a magnetic sensor configured to sense a first magnetic flux of the output transformer. The magnetic sensor generates a flux signal responsive to the first magnetic flux. Control circuitry is configured to receive the flux signal and to generate a control signal responsive to the flux signal. A winding is configured to receive the control signal and to induce a second magnetic flux within the output transformer responsive to the control signal, the second magnetic flux having opposite polarity to the first magnetic flux. The second magnetic flux may maintain a non-zero quiescent magnetic bias level within the output transformer, or may substantially cancel or null the DC and low-frequency subsonic components of the first magnetic flux.

Abstract: An amplifier circuit includes a transistor having a control terminal, a first and a second terminal, a signal input terminal coupled to the control terminal of the transistor, as well as a transformer with a primary side and a secondary side, the primary side of which is coupled to the first or second terminal of the transistor. The amplifier circuit further includes a signal output terminal coupled to the secondary side of the transformer. Hereby it is possible to provide an amplifier circuit with a better characteristic as opposed to a conventional amplifier circuit, which is further easy to manufacture.

Abstract: A method for transforming single-ended signals outputted from a low-noise amplifier of a wireless transceiver into differential signals. The method includes: providing a transformer according to a default requirement of the wireless transceiver; transferring the single-ended signals provided by the low-noise amplifier to a first end of a primary end of the transformer, and coupling a second end of the primary end of the transformer to a power source; grounding a center tap of a secondary end of the transformer; and outputting the differential signals from two ends of the secondary end of the transformer.

Abstract: An inverting adapter is disclosed that inverts inverted DVB-ASI signals to produce an adapted DVB-ASI signal. This adapted DVB-ASI signal may be used by any DVB-ASI device. The inverting adapter can be contained in one small package and easily connected to any of the various amplification devices that produce inverted DVB-ASI signals. Alternatively, the inverting adapter of the present invention may be integrally formed with an amplification device to automatically provide the adapted DVB-ASI signal.

Abstract: A multi-level power amplifier architecture using a multi-tap transformer implemented on a single CMOS integrated circuit wireless communications device is described. By providing a multi-tap transformer for coupling a plurality of power amplifiers to a shared output impedance, such as an antenna, power transmission may be made at different levels while maintaining efficiency. With a multi-tap transformer having “N” taps featuring “N” different impedance levels, each tap may be connected to an amplifier cell which delivers power into the transformer at the tap for coupling to the output load. Any one of the “N” amplifier cells can be turned on at once along with any combination of the “N” amplifier cells.

Abstract: A radial power divider-combiner is disclosed. The divider-combiner includes a divider and a combiner. An input signal is provided to a transmission antenna that radiates the input signal inside the divider. Within the divider, the input signal is divided into a plurality of individual signals. The individual signals are received by receiving antennas and provided to respective amplifiers. The amplifiers amplify the respective individual signals by a desired amplification factor. The amplified individual signals are provided to a plurality of transmitting antennas within the combiner. Inside the combiner, the amplified individual signals are combined to form an output signal that is received by a receiving antenna in the combiner.

Abstract: A circuit for matching the impedance of an output load to an active device includes a transformer including a first winding having a terminal for coupling to the output of the active device and a second winding electromagnetically coupled to the first winding, and a plurality of taps, each of the plurality of taps having a first end coupled to a position on the second winding corresponding to a ratio of the second winding to first winding differing from other ones of the plurality of taps, and a second end. The matching circuit further includes a plurality of MEMS switches each having a control input for receiving a corresponding control signal, a first terminal coupled to the second end of a corresponding one of the plurality of taps, and a switched output selectively coupled to a matching junction in response to the corresponding control signal.

Abstract: Disclosed is a demodulation apparatus for a digital audio amplifier capable of solving a space, cost and heat generation of the digital audio amplifier. The demodulation apparatus includes a first inductor connected between a positive digital audio signal output terminal and one end of a load, a second inductor connected between a negative digital audio signal output terminal and the other end of the load, and magnetically coupled to the first inductor, a first capacitor connected between the one end of the load and ground and coupled to the first inductor for serving as a low-pass filter, and a second capacitor connected between the other end of the load and ground and connected to the second inductor for serving as a low-pass filter.

Abstract: A bidirectional equalizer arrangement for cancelling the effect of residual capacitance and/or residual resistive loss in a separation filter having a low-pass filter and a high-pass filter. The equalizer comprises a differential amplifier whose input forms the equalizer's connection terminals, and whose output is coupled, via a transformer, to a positive feedback circuit that includes the transformer's secondary winding, a capacitor and a resistor of predetermined values. When the equalizer is operatively coupled to the low-pass filter, the positive feedback circuit produces a feedback current of opposite polarity and equal magnitude to that produced by the residual capacitance and/or the residual resistive loss, thereby substantially cancelling their effect. The equalizer may be advantageously used with an ADSL/POTS separation filter.

Abstract: An RF amplifier system having improved power supply is presented and which includes a plurality of power amplifiers each having an output circuit for connecting a DC voltage source to one of a plurality of primary windings located on a first transformer. The first transformer has a plurality of secondary windings located thereon with each being a single turn secondary winding. The secondary windings are connected together in series. A second transformer is located in a cascaded arrangement with the first transformer and has a like plurality of single turn primary windings connected together in series and a like plurality of secondary windings are on said second transformer with each being connected to a rectifier for providing a controlled DC voltage.

Abstract: Continuous alternating current is derived from a differential operational amplifier supplied by direct current. The differential operational amplifier produces alternating current located on the positive input of the differential operational amplifier. Output of the differential operational amplifier is received by a transformer to produce alternating current. Voltage from the transformer is fed back to the negative input of the differential operational amplifier to provide feedback for the differential operational amplifier. Whereby direct current provided to a differential operational amplifier is transformed to continuous alternating current.

Abstract: A line driver combining active impedance and filter in one stage for connection to a transmission line having a characteristic impedance. The line driver comprises an amplifier, a transformer with a primary to secondary winding ratio of 1:n, a reference impedance, an input impedance and two feedback impedances. The primary winding of the transformer has a first end connected to the output of the amplifier and the secondary winding is connectable to the transmission line. The reference resistor has an end connected to the second end of the first winding at a junction node and the feedback circuit is connected to the input and output of the amplifier and also to the junction node. The reference impedance has a value equal to n 2 K times the characteristic impedance of the transmission line.

Abstract: A fiber-to-the-home (FTTH) system transmits forward and reverse optical signals, such as video, voice, and data signals, via optical fiber, and includes a plurality of home network units. The home network units include an FTTH optical receiver for receiving at least one of the video, voice, and data signals. A triplexer distinguishes and separates the video, voice, and data signals, wherein the video signals have a first wavelength and the voice and data signals have a second wavelength. The voice and data signals are provided to the home network unit for further processing. The triplexer provides an electrical signal to the amplifier stages. The amplifier stages include a preamplifier stage and a postamplifier stage. A gain control circuit automatically adjusts the gain of the video signal based upon the input power level to the FTTH optical receiver. Additionally, a tilt network performs level compensation for externally located coaxial cable.

Abstract: A line driver combining active impedance and filter in one stage for connection to a transmission line having a characteristic impedance. The line driver comprises an amplifier, a transformer with a primary to secondary winding ratio of 1:n, a reference impedance, an input impedance and two feedback impedances. The primary winding of the transformer has a first end connected to the output of the amplifier and the secondary winding is connectable to the transmission line. The reference resistor has an end connected to the second end of the first winding at a junction node and the feedback circuit is connected to the input and output of the amplifier and also to the junction node. The reference impedance has a value equal to n2 /K times the characteristic impedance of the transmission line. The feedback circuit is arranged to produce a voltage at the output of the amplifier substantially equal to (K+1) times the voltage at the junction node, for a predetermined value of K.

Abstract: A high potential/high efficiency amplifier contains at least two separate amplifiers. One amplifier is used for the typical inputs that are received from an input source and a second amplifier is used solely for peak inputs. Utilizing the second amplifier to handle the peak inputs allows the first amplifier to concentrate solely on the typical inputs. A small resistor tied to the output of the second amplifier reduces the output of the second amplifier. Thus, when the output of the first and second amplifiers are equal, the output of the first amplifier will be applied to the load. When the input exceeds the operational value for the first amplifier, the first amplifier logically disconnects itself from the load and the output of the second amplifier is applied to the load. Once the input returns to a value within the limits of the first amplifier, the first amplifier becomes operational again, and the resistor again becomes a barrier to the second output being applied to the load.