Abstract: The specification and drawings present a new method and apparatus for using transferred-impedance filtering in RF (radio frequency) receivers (e.g., inside of a mobile communication device), wherein said filtering can be done with MOS-switches transferring impedance of a regular RC or RCL circuit to RF frequency filtering inside an RFIC (radio frequency integrated circuit).

Abstract: Switched capacitor notch filter circuits are disclosed.

Abstract: In one embodiment, a method for a control interface includes: receiving a signal conveying bits of information over a single line; and for each bit of information, comparing the proportion of time that the signal on the single line is low versus the proportion of time that the signal on the single line is high for a respective bit period defined from one operative edge of the signal to the next operative edge of the signal in order to determine a logic value for that bit of information.

Abstract: A modulation ratio enhancement circuit increases the modulation ratio of a current signal which is ASK-modulated with signal data. A branch unit, an average value detection unit, a comparator and a buffer constitute a demodulation unit so that the signal data is demodulated from a current signal of which the modulation ratio is increased by the modulation ratio enhancement circuit.

Abstract: A semiconductor integrated circuit has an amplifier circuit which includes a phase compensating capacitor and has a feedback loop, and a stability determining and adjusting circuit which measures an amplitude of a voltage outputted from the amplifier circuit at a predetermined plurality of frequencies and adjusts a capacitance value of the phase compensating capacitor on the basis of a ratio between measured values of the amplitude.

Abstract: An operational amplifier capable of compensating offset voltage includes an input stage circuit having a positive input end, a negative input end, a first current output end, and a second current output end, for outputting current corresponding to voltage received by the positive and negative input ends, an output stage circuit coupled to the first current output end and the second current output end of the input stage circuit, for outputting voltage according to current outputted from the first current output end and the second current output end, and an trimming device coupled between the input stage circuit and the output stage circuit, for adjusting current of the first current output end or the second current output end for compensating offset voltage.

Abstract: 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.

Abstract: Active circuits with isolation switches are described. In one design, an apparatus includes first and second amplifiers coupled in parallel. Each amplifier receives an input signal and provides an output signal. Each amplifier has a switch that isolates the amplifier when the amplifier is turned off. The first and second amplifiers may be high and low gain amplifiers or two low noise amplifiers (LNAs). The first and second amplifiers may be for different communication systems, different frequency bands, and/or different gain ranges. In general, any number of amplifiers may be coupled in parallel, and each amplifier may have a switch to isolate that amplifier when turned off. A switch for an amplifier may be a shunt switch coupled between an internal node of the amplifier and ground. The shunt switch may be closed when the amplifier is turned off and may be opened when the amplifier is turned on.

Abstract: Parasitic coupling effects between RF or microwave transistors provided in a common package are compensated by connecting one or more capacitors between the transistors. By connecting the capacitor(s) at a location that corresponds to the site of the coupling, the compensation is effective over a wide frequency band. This coupling-compensation makes it feasible to provide, in a common package, RF or microwave transistors intended to operate in quadrature, thereby improving performance matching and operating efficiency of the overall device.

Abstract: A current feedback-type operational amplifier comprising multiple input parts and one output part, wherein each of the multiple input parts comprises a first input terminal, a second input terminal, and an output terminal, the signals input from the first input terminal are buffer amplified and output to the second input terminal, and current is output to the output terminal in an amount corresponding to the current that flows to the second input terminal; the output terminal part comprises an input terminal and an output terminal, signals obtained by adding in terms of current the signals of all of the input parts are input to the input terminal, and the signals input to the input terminal are converted to voltage signals, amplified, and output to the output terminal; and one of the above-mentioned input parts is made effective and the other input parts are made ineffective in response to first external signals, the impedance of the first input terminal, the second input terminal, and the output terminal of

Abstract: A digital input class-D amplifier includes a decoder which outputs a plurality of lines of time-series digital signals having a density of 1 or 0 conforming to an input digital signal, an error integrator which integrates a difference between a drive waveform to be applied to a load and a sum of the plurality of lines of time-series digital signals output from the decoder, and a modulation circuit which generates a pulse modulated with a pulse width or a pulse density based on a result of integration performed by the error integrator. The load is driven in accordance with the pulse generated by the modulation circuit.

Abstract: Method and means for random or systematic mismatch compensation for a memory sensing system are disclosed. A sense amplifier includes a bulk voltage source to set the bulk of the sensing transistor to be a voltage different than the voltage driving the sensing transistor. For an NMOS sensing transistor, a triple well is used with the variable bulk voltage. Differential sense amplifiers with various offset compensation are included. Intentional offset creation for useful purpose is also included.

Abstract: A variable gain amplifier includes multiple gain stages. Each gain stage includes a gain transistor and a cascode transistor to form a cascode amplifier, and a current diversion transistor to divert current away from a cascode transistor to reduce gain in the stage. A control circuit is included to maintain substantially constant drain-to-source voltage and drain current in the gain transistor.

Abstract: A common-mode voltage controller for adjusting common-mode voltages between a first buffer and a second buffer at a subsequent stage or a preceding stage of the first buffer in a signal transmission circuit, comprising: a first reference voltage generation unit for generating a common-mode voltage corresponding to the first buffer; a second reference voltage generation unit for generating a common-mode voltage corresponding to the second buffer at the subsequent stage or the preceding stage; and a control signal generation unit for generating a control signal for controlling a common-mode voltage of the first buffer according to a difference voltage between an output of the first reference voltage generation unit and an output of the second reference voltage generation unit, and giving the control signal to the first buffer and first reference voltage generation unit.

Abstract: A rail-to-rail amplifier for amplifying an analog signal from a DAC includes a first differential input section, which includes an n-channel transistor pair, a second differential input section, which includes a p-channel transistor pair, a first current supply provided between the second differential input section and a high voltage side supply, and a current controller for the second input section provided between the first current supply and the second differential input section for controlling the current supply to the second differential input section in accordance with data of a predetermined bit position in input digital data to the DAC.

Abstract: A transmission line amplifier utilizes a transmission line transistor having a gate line, and first and second lines. The gate line is a gate of the transistor, one of the first and second lines is a source of the transistor, and the other is a drain of the transistor. The gate line includes an input terminal at a first end thereof, adapted to receive an input signal, and a gate line load terminal at a second end thereof, adapted to be connected to a gate line load. The second line is connected to a first supply voltage. The first line includes a first line load terminal at a first end thereof that is adapted to be connected to a first line load, and an output terminal at a second end thereof that is adapted to provide an output signal.

Abstract: A wide-band adjustable gain low-noise amplifier (LNA) is disclosed. In various embodiments, the LNA includes a first inverting amplifier configured to generate a first intermediate signal. A first attenuator is configured to receive the first intermediate signal and to generate a second intermediate signal. In various embodiments, the LNA includes a second attenuator configured to generate a third intermediate signal. A second inverting amplifier is configured to generate a fourth intermediate signal using the third intermediate signal. A summing circuit is configured to generate an output signal based on the second and the fourth intermediate signals. Apparatus and methods according to various embodiments of the invention are also disclosed.

Abstract: A transconductance control circuit, comprising: a test transconductance circuit for providing an output current from a reference voltage; apparatus for deriving a bias current for the test transconductance circuit from the output current, the bias current including a component that varies with temperature and a component that varies with process; and apparatus for providing the bias current to other transconductance circuits.

Abstract: Variable gain amplifiers with controllable gain gradient over temperature. A variable gain amplification circuit comprises an input terminal receiving an input signal, an output terminal outputting an output signal, and a control terminal receiving a first gain control signal. The relationship between gain of the variable gain amplification circuit and temperature is programmable rather than temperature independent, and is controlled by the first gain control signal obtained by a second gain control signal and a third gain control signal.

Abstract: A frequency jittering control circuit wherein by means of the characteristics of a PLL whose input switches between different frequencies, the output frequency of the PLL swings between the different frequencies to achieve the desired frequency jittering.

Abstract: In an ultrasonic operation apparatus according to the present invention, in order to detect the initial resonance frequency (Fro) promptly once a foot switch is pressed, under the control of a sweeping speed control circuit, the D/A converter D/A converts 8-bits of signals (phase difference amount signal ??) representing the amount of the phase difference detected by the phase comparator, and the output of the D/A converter is output to a VCO so as to become a clock for a sweep circuit. When a phase difference amount between ?i and ?v is large and a drive frequency setting signal (Es) is far from Fro, the sweeping speed for Fro detection is increased. When a phase difference amount between ?i and ?v is small and Ps is close to Fro, the sweeping speed for Fro detection is decreased.

Abstract: A method is provided for reducing inter modulation distortion products using multi-carrier phase alignment of the type where a combined carrier signal is generated from the combined output carried waves of a plurality of numerically controlled oscillators in which the frequency of the carrier wave can be altered by changing an input value into the oscillator. In particular the initial phase of the output carrier waves is adjusted so that the peak amplitude of the combined carrier signal is minimized so that compression of the higher amplitude portions of the combined signal is reduced.

Abstract: A temperature-dependent oscillator includes a first current source, wherein a first current provided by the first current source has a positive temperature coefficient, a second current source serially connected to the first current source, wherein a second current provided by the second current source has a negative temperature coefficient, and a capacitor serially connected to the first current source and parallel connected to the second current source.

Abstract: An oscillator assembly includes an oscillator circuit that is configured to generate a frequency signal. A temperature compensation circuit is in communication with the oscillator circuit and adapted to adjust the frequency signal in response to changes in temperature. The oscillator and temperature compensation circuits are located within an oven. A heater and a temperature sensor in communication with the heater are also both located in the oven. The temperature sensor is adapted to directly control the heater in response to changes in temperature. In one embodiment, the oscillator components are mounted to a ball grid array substrate which, in turn, is mounted on a printed circuit board. In this embodiment, a resonator overlies the ball grid array substrate and a lid covers and defines an oven and enclosure for the resonator and the ball grid array substrate. The oscillator and temperature compensation circuit are defined on the ball grid array substrate.

Abstract: Methods and apparatus for controlling frequency in a crystal oscillator are provided that allows for continued reception of GPS signal solution in a continuous high G environment. One method comprises measuring G-forces asserted on the crystal oscillator, determining a shift in frequency of the crystal oscillator due to the measured G-forces, determining a temperature that would shift the crystal oscillator's frequency back to a rate that would occur without the measured G-forces, and changing the temperature of the crystal oscillator based on the determined temperature to shift the crystal oscillator's frequency back to a rate that would occur if the G-forces were not present.

Abstract: There is provided a method and apparatus for output pulse width modulation in a digital amplifier including: a determining step of adding or subtracting a value corresponding to a predetermined offset to or from an input audio signal alternately according to a period of the input audio signal, thereby determining a sign of a resulting value of adding or subtracting; a switching step of outputting the input audio signal to a first port when the determined sign is positive, and outputting the input audio signal to a second port after inverting the input audio signal into a positive number when the determined sign is negative; an adjusting step of adding a value corresponding to a pulse width for a minimum time required for switching to the audio signals output from the first port and the second port, and outputting a resulting value of adding; and a modulating step of performing pulse width modulation on the audio signals output from the adjusting step and outputting a first modulation signal and a second modul

Abstract: In a phase locked loop (PLL), phase shifters shift a phase of an input signal. Based on the phases of the input signal, the shifted signals, and a frequency division output signal, phase frequency detectors (PFDs) generate phase difference signals. In response to the phase difference signals, charge pumps (CPs) control output voltages thereof. Based on the output voltages of the CPs, a voltage controlled oscillator (VCO) outputs an output signal. A frequency divider divides the frequency of the output signal from the VCO to generate the frequency division output signal. A circulator outputs the frequency division output signal to one of the PFDs at a proper timing. A modulator reduces quantization errors of the frequency divider.

Abstract: A balance filter includes a first filter having first multimode surface acoustic wave (SAW) filters connected in parallel, a second filter that is connected to the first filter and includes a second multimode SAW filter, a first terminal connected to the first filter, and second terminals connected to the second filters. An input terminal of the balance filter is one of the first and second terminals, and an output terminal thereof is the other. Electric signals transmitted from the first to second filters or vice versa are in opposite phase. Electric signals are input or output via the second terminals in opposite phase.

Abstract: Circuitry, architectures, devices and systems for multi-band radio communications using a balanced-unbalanced duplexer. An integrated balanced-unbalanced duplexer for multi-band communications may include an unbalanced multi-band port; a first balanced single-band port; a second balanced single-band port; a first unbalanced coupling arm conductively coupled to the unbalanced multi-band port; a second unbalanced coupling arm conductively coupled to the unbalanced multi-band port; a first pair of balanced coupling arms conductively coupled to the first balanced single-band port and electromagnetically coupled to the first unbalanced coupling arm; and a second pair of balanced coupling arms conductively coupled to the second balanced single-band port and electromagnetically coupled to the second unbalanced coupling arm. The architectures and/or systems generally include components embodying one or more of the concepts disclosed herein.

Abstract: Embodiments of the invention provide an adaptive notch filter that employs a power detector as a feedback control mechanism to steer the notch filter. One such embodiment of the invention provides adaptive control of the notch filter capacitor to tune the notch filter frequency based upon a diode power detector. One embodiment of the invention provides a system including multiple cascaded adaptive notch filters each having a feedback control method from a power detector to separately control each filter. For one embodiment of the invention a method is disclosed for tuning an adaptive notch filter using a dithering process to determine a minimum power output at the power detector. One embodiment includes an adaptive notch filter implementing a device with a tunable resonance frequency.

Abstract: A method and apparatus for joint training of an analog equalizer (AEQ) and an analog echo canceller (AEC), which both process an input analog signal in the analog domain. In one embodiment, the method includes joint training the AEQ and the AEC using independent analog error signals.

Abstract: A bipolar pulse generator circuit generates bipolar pulses and provides an impedance transformation. The circuit is amenable for implementation in a variety of configurations depending on the size and pulse width requirements for the design. It also maximizes energy transfer and may be implemented in a straight forward, easy manner. The generator may be implemented with one or two switches in a three, five or more transmission line implementation and may include inductive stub, which is inherent element of transmission line transformers. The generator may also be implemented in a multi-layer folded configuration, with or without the addition of a ground potential conductor. The generator may also be implemented in stacked or/and balanced configurations.

Abstract: An active balun for improving a phase matching characteristic includes a transistor part which has an input terminal receiving an input signal and first and second output terminals which output signals corresponding to the input signal, and a capacitance matching part provided on the side of one of the first and second output terminals which matches capacitances as seen from the first and second output terminals. The capacitance matching part may be composed of a transistor which bleeds a current from the one output terminal.

Abstract: A balanced-unbalanced transformation device includes a plate-like dielectric substrate having a ground electrode and a plurality of major surface electrodes formed thereon. Two of the major surface electrodes are connected to the ground electrode via short-circuit side surface electrodes so as to form ¼ wavelength resonator transmission lines. A third major surface electrode is disposed between the two major surface electrodes and has either end open so as to form a ½ wavelength resonator transmission line. A balancing characteristic adjustment side surface electrode is provided on a side surface of the dielectric substrate. By adjusting a capacitance formed between the balancing characteristic adjustment side surface electrode and the third major surface electrode, a phase balance between two balanced signals is set to a desired value.

Abstract: Various embodiments are described herein for a combiner. The combiner includes first and second transmission lines, a dielectric material disposed about the first and second transmission lines, an intermediate conductor arrangement disposed about the dielectric material, and an outer conductor arrangement disposed about the intermediate conductor. The dielectric material has a dielectric constant higher than that of air, and the intermediate conductor arrangement has reactive portions.

Abstract: An active step attenuator can attenuate the RF signal from a cable modem or other RF source. The active step attenuator converts the RF energy into a DC control signal that controls the attenuation applied to the RF signal. The voltage of the control signal is proportional to the RF energy, so that the active step attenuator attenuates a stronger RF signal more than a weaker RF signal. The active step attenuator may be in the form of a diplex circuit, one branch of which passes signals in one frequency band without attenuation and the other branch of which actively attenuates signals in another frequency band.

Abstract: A SAW filter device includes a SAW filter chip in which one-port surface acoustic wave resonators each including an IDT made of Al or an Al alloy, are provided on a ?-rotated Y-cut X-propagation LiNbO3 substrate. The cutting angle ? of the ?-rotated Y-cut X-propagation LiNbO3 substrate is in the range between about 50° and about 55°. The normalized film thickness of the IDT 100h/? (%) (h denotes the thickness of the IDT and ? denotes the wavelength of a surface acoustic wave) is in the range between about 2% and about 4%. The duty ratio of the IDT is equal to or less than about 0.4.

Abstract: A chip device having a ground electrode and a plurality of top-surface electrodes on a plate-like dielectric substrate. Two of the top-surface electrodes are connected to the ground electrode via respective short-circuit side-surface electrodes to form quarter wavelength resonant lines. A third top-surface electrode is provided between the two top-surface electrodes and both ends thereof are opened to form a half wavelength resonant line. The two top-surface electrodes each have a parallel portion arranged near and in parallel to the third top-surface electrode and a flexion that curves from the parallel portion, extends toward the remaining of the two top-surface electrodes, and is jump-coupled to the remaining of the two top-surface electrodes. The short-circuit side-surface electrodes are jump-coupled to each other, like the flexions.

Abstract: Provided is a digital attenuation apparatus having ultra broadband and excellent attenuation characteristics. The digital attenuation apparatus includes an input port, an output port, a first transmission line, a second transmission line, a first switching device, a third transmission line, a first resistive element, a second resistive element, a fourth transmission line, a second switching device, a fifth transmission line, and a third resistive element.

Abstract: Various methods and devices are provided for attenuating RF signals propagating within a waveguide. In particular, a plurality of coaxial probes are incorporated into the waveguide for the purpose of attenuating X-band RF signals. In one embodiment, a 7-bit, 3 dB linear digital attenuator is provided having a waveguide in a racetrack configuration. Coaxial probes in communication with the waveguide are adapted to couple energy to and from a signal traveling within the waveguide. The attenuator can also include switches adapted to reflect coupled energy back into the waveguide or pass the coupled energy to a resistive termination.

Abstract: A central magnet of a plurality of magnets arranged to be different in polarities is detected by two hall ICs; therefore, reduction in size can be achieved by reducing the number of the magnets; and at the same time, the number of the hall ICs can be maintained and the reliability can be secured, as compared with a configuration in which the magnets and the hall ICs individually respond in one to one correspondence.

Abstract: The invention relates to a magnetic actuating device containing a reference element and an adjusting element which is movably disposed between first and second end positions with respect to the reference element. The reference and/or adjusting elements contain a magnetizable material. A drive coil is provided for generating a magnetic field that moves the adjusting element from the first to the second end position. A mechanical clamping device is provided for producing mechanical forces that move the adjusting element from the second to the first end position. A fixing device is provided with a permanent magnet for generating a holding force fixing the adjusting element in the second end position with respect to the reference element. The fixing device contains a fixing unit separated from the adjusting element and provided with the permanent magnet.

Abstract: The invention relates to a proportional magnet, including a winding carried by a coil body, two pole shoes which project into the coil body from opposite sides and which are spaced apart axially from one another, and a gap provided between the pole shoes. The invention further includes a magnet armature, which is arranged within the winding in an axially displaceable manner substantially parallel to the longitudinal axis thereof. The axial movement of the magnet armature can be transmitted to a valve member. The invention still further includes an electrically conductive element, wherein the magnet armature can be moved through the element, wherein the element is formed from a basic body having an electrically conductive layer, and wherein the electrically conductive layer is applied separately to the basic body.

Abstract: A system for improved magnetization of flexible magnetic sheet material, such as magnetic rubber. More particularly, this invention relates to providing a system for magnetization of pre-printed flexible magnetic sheet material.

Abstract: A magnet arrangement comprising a superconducting magnet coil system (M) for generating a magnetic field in the direction of a horizontal z-axis in a working volume (V) disposed along the z-axis about z=0 with at least one radial access to the working volume (V) perpendicular to the z-axis, wherein the magnet coil system comprises at least one partial coil winding (A1a, A1b) disposed coaxially about the z-axis at z>0, and at least one partial coil winding (B1a, B1b) disposed coaxially about the z-axis at z<0, is characterized in that at least one of the partial coil windings (A1a, A1b) at z>0 as well as at least one of the partial coil windings (B1a, B1b) at z<0 are supported by a common coil body (K1), wherein the coil body (K1) has at least one opening (O1) at z=0, which permits radial access to the working volume (V), wherein the coil body (K1) supports the axial magnetic forces between the partial coil windings and wherein the coil body is force-fit mechanically connected to a first side plate

Abstract: A ferrofluid chamber has a housing that is adapted to be coupled to a component that generates a magnetic field of sufficient strength to stimulate anatomical tissue. In addition, a ferrofluid is disposed within the housing for cooling the component.

Abstract: A magnetic part having a first iron core wound with a winding constituting a transformer and an inductance component of a parallel coil and a second iron core wound with an inductance component of a series coil, in which a ratio of the dimensions of the first iron core and the second iron core are in accordance with their respective winding densities.

Abstract: The invention relates to an ignition coil for an internal combustion engine. Said ignition coil comprises a primary coil base (2) carrying a primary winding (1) and having an especially cylindrical shape, a low voltage connection area (10) for connecting the primary winding (1) to a low voltage, a secondary winding (3) inductively coupled to the primary winding (1) and disposed on an especially cylindrical secondary coil base (4), for providing a high voltage for the spark plug of the internal combustion engine. The primary coil base (2) and the secondary coil base (4) are mounted concentric to one another. The ignition coil also comprises a high-voltage connection area (5) in which the secondary winding (3) contacts the spark plug. The aim of the invention is to improve the ignition coil of the aforementioned type with respect to its electromagnetic compatibility.

Abstract: A core-coil device includes: a printed circuit board having upper and lower surfaces and formed with a pair of through-holes that are spaced apart from each other and that extend through the upper and lower surfaces, the printed circuit board being further formed with at least one conductive coil winding that surrounds one of the through-holes; and at least one loop-shaped magnetic core of an integrally molded single piece extending through said one of the through-holes in the printed circuit board.

Abstract: There is provided an isolated power converter. More particularly, in one embodiment, there is provided a power converter including a first magnetic core having a primary winding and a secondary winding around the first magnetic core. The power converter also includes a second magnetic core having a first leg, a second leg coupled to the first leg, and a third leg coupled to the first and second legs, wherein a part of the third leg is equidistant from the first leg and the second leg. The power converter also has a first winding encircling the first leg, a first end of the first winding coupled to the secondary winding, a second winding encircling the second leg, a first end of the second winding coupled to the secondary winding, and a third winding encircling the third leg, a first end of the third winding coupled to a second end of the first wining and to a second end of the second winding.