Abstract: Disclosed in one embodiment is filter circuitry having first and second paths extending between first and second nodes. The first path has a first inductor and a second inductor coupled in series between the first node and the second node, wherein the first inductor and the second inductor are positively coupled with one another, and a first common node is provided between the first inductor and the second inductor. First shunt acoustic resonators are coupled between the first common node and a fixed voltage node. The second path includes a third inductor and a fourth inductor coupled in series between the first node and the second node. The third inductor and the fourth inductor are negatively coupled with one another, and a second common node is provided between the third inductor and the fourth inductor. Second acoustic resonators are coupled between the second common node and a fixed voltage node.

Abstract: A transceiver includes: a power amplifying circuit arranged to generate differential output signals during a transmitting mode of the transceiver; a balance-unbalance circuit arranged to convert the differential output signals into a single-ended output signal; a switchable matching circuit arranged to receive the single-ended output signal on a signal port of the transceiver during the transmitting mode, and to convert a single-ended receiving signal on the signal port into a single-ended input signal during a receiving mode of the transceiver; and a low-noise amplifying circuit arranged to convert the single-ended input signal into a low-noise input signal during the receiving mode. The power amplifying circuit, the Balun, the switchable matching circuit, and the low-noise amplifying circuit are configured as a single chip.

Abstract: In one embodiment, the present invention includes a transformer formed on a semiconductor die. Such transformer may have multiple coils, including first and second coils. Each coil may have segments that in turn are formed on a corresponding metal layer of the semiconductor die. The segments of a given coil are coupled to each other, and the first and second coils can be interdigitated with each other.

Abstract: A novel and useful radio frequency (RF) front end module (FEM) circuit that provides high linearity and power efficiency and meets the requirements of modern wireless communication standards such as 802.11 WLAN, 3G and 4G cellular standards, Bluetooth, ZigBee, etc. The configuration of the FEM circuit permits the use of common, relatively low cost semiconductor fabrication techniques such as standard CMOS processes. The FEM circuit includes a power amplifier made up of one or more sub-amplifiers having high and low power circuits and whose outputs are combined to yield the total desired power gain. An integrated multi-tap transformer having primary and secondary windings arranged in a novel configuration provide efficient power combining and transfer to the antenna of the power generated by the individual sub-amplifiers.

Abstract: A novel and useful radio frequency (RF) front end module (FEM) circuit that provides high linearity and power efficiency and meets the requirements of modern wireless communication standards such as 802.11 WLAN, 3G and 4G cellular standards, Bluetooth, ZigBee, etc. The configuration of the FEM circuit permits the use of common, relatively low cost semiconductor fabrication techniques such as standard CMOS processes. The FEM circuit includes a power amplifier made up of one or more sub-amplifiers having high and low power circuits and whose outputs are combined to yield the total desired power gain. An integrated multi-tap transformer having primary and secondary windings arranged in a novel configuration provide efficient power combining and transfer to the antenna of the power generated by the individual sub-amplifiers.

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: Disclosed herein is a power amplifier. The power amplifier includes N power amplification means, a transformer, and a harmonic elimination unit. Each of the N power amplification means amplifies an input signal into a predetermined level. The transformer includes N/2 primary windings respectively connected to the output terminals of the power amplification means and a secondary winding configured such that coil elements are connected in series between an output terminal and a ground, and sums power transmitted from the primary windings. The harmonic elimination unit is disposed across both ends of the secondary winding of the transformer, and eliminates the output of the harmonic frequencies of a preset frequency.

Abstract: Double transformer balun for maximum PA (Power Amplifier) power. A novel approach is presented herein by which conversion from a differential signal to single-ended signal may be achieved using a double transformer balun design. The secondary coils of the double transformer balun also operate as a choke for the PA supply voltage. The secondary coils can operate as an RF (Radio Frequency) trap or choke to keep any AC (Alternating Current) signal components and to pass any DC (Direct Current) components. By using a double transformer balun design, relatively thinner tracks may be employed thereby ensuring a high degree of electromagnetic coupling efficiency and high performance. Also, these relatively thinner tracks consume a relatively small amount of space on the die. The double transformer balun design also includes a matching Z (impedance) block that is operable to match the Z of an antenna or line that the PA is driving.

Abstract: A switchable power combiner is disclosed. The switchable power combiner has an output section that is a signal source connected to a transformer section. The transformer section has one or more primaries and a common secondary. The transformer primaries and secondary are acoustically coupled. The primaries or/and the secondary are made of switchable piezoelectric material, such that the acoustic coupling between any primary and the secondary can be switched on or off by electrical control, thereby implementing a switchable power combiner. The transformer secondary is connected to an antenna port. The power amplifier output section is segmented and connected to the transformer primaries. The power amplifier output section has a plurality of power amplifiers and a plurality of reactance elements, either fixed or variable. The switchable power combiner generates different linear load lines by switching on and off the coupling between any primary and the secondary.

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: 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: 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: 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: A power amplifier apparatus includes a pair of power amplifiers for performing switching-type power amplification, a transformer, and a capacitor. The transformer is formed of a pair of coils that are connected in series between the corresponding output terminals of the pair of power amplifiers and the corresponding terminals of a speaker. The capacitor is connected in parallel with the output terminals of the pair of coils. With this configuration, a mutual inductance and a leakage inductance are generated in the coils. As a result, 180° out-of-phase and in-phase noise components contained in an output of the power amplifier apparatus can be eliminated.

Abstract: A transconductance amplifier circuit employs the known combination of a transconductance amplifier and a current comparator (with or without a ratio extender, preferably in the form of a two-stage current transformer) to compare the output current from the transconductance amplifier with that flowing through a reference resistor, both these currents having been derived from the same alternating input voltage. A current corresponding to the unbalanced ampere-turns in the current comparator is used to produce a feed-forward error signal that is used to modify the output of the transconductance amplifier. The invention is characterized by an output transformer that has coaxial inner and outer toroidal magnetic cores, and primary and correction windings outside the outer core. This primary winding receives the output current from the transconductance amplifier and the correction winding receives the error signal.

Abstract: In a sound system having a sound source for generating sound signals, a low-impedance amplifier for amplifying the generated sound signals, and high-impedance loudspeakers for reproducing audible sound from the amplified sound signals, an impedance conversion device having a step-up transformer section is disconnectably connected between the amplifier and the high-impedance speakers. The output side of the low-impedance amplifier is also connected directly to low-impedance loudspeakers. Thus the sound system can be operated to selectively broadcast either monaural sound or binaural stereo music of high quality.

Abstract: A switching amplifier for producing large output power signals, including a plurality of amplifier stages having signal inputs driven in parallel and series connected outputs. The amplifier stages amplify pulse signals representative of an input signal with as little distortion as possible in a wide frequency band, and in particular exhibit very high insulation and very low capacity. The amplifier stages therefore include switching amplifiers each including a transformer having a toroidal core of low remanence material, a secondary winding formed of plural turns of rf stranded wire wound on the toroidal core, an insulating housing surrounding the secondary winding, a primary winding formed of plural turns of rf stranded wire disposed on the insulating housing, an outer housing confining the transformer and being filled with an insulating material, and a metallic mandrel within the bore of the toroidal core.

Abstract: A low frequency transformer for an audio system has a core, a primary winding, a secondary winding, insulation between the primary and secondary windings, a tertiary winding, and insulation between the secondary and tertiary windings. One end of the tertiary winding is embedded in the insulation between the secondary and tertiary windings, and the other end is grounded. With a tertiary winding arranged and connected in this fashion, the effects of external interference signals are substantially eliminated, and the output of the transformer is improved, i.e., it has less waveshape and frequency distortion. Preferably, the primary and tertiary windings are wound around the core in the same direction while the secondary winding is wound around the core in the opposite direction.