Abstract: The present invention, generally speaking, provides for high-efficiency power control of a high-efficiency (e.g., hard-limiting or switch-mode) power amplifier in such a manner as to achieve a desired modulation. In one embodiment, the spread between a maximum frequency of the desired modulation and the operating frequency of a switch-mode DC-DC converter is reduced by following the switch-mode converter with an active linear regulator. The linear regulator is designed so as to control the operating voltage of the power amplifier with sufficient bandwidth to faithfully reproduce the desired amplitude modulation wave-form. The linear regulator is further designed to reject variations on its input voltage even while the output voltage is changed in response to an applied control signal. This rejection will occur even though the variations on the input voltage are of commensurate or even lower frequency than that of the controlled output variation.

Abstract: A signal amplifier circuit comprises a signal amplifier having an input for receiving an ac signal to be amplified and an amplifier biasing arrangement coupled between the signal input and a dc voltage line, the arrangement comprising a diode means and a bootstrapping amplifier connected across the diode means.

Abstract: An electrostatic loudspeaker requires a high voltage DC bias power supply to bias the stators and diaphragms of electrostatic speakers. A self biased power supply eliminates the need for an external power supply by deriving a high voltage bias from the stator AC signal voltages which have been rectified and run from a high voltage tap and/or through a voltage multiplier which has a voltage limiting means.

Abstract: A signal line drive circuit according to the present invention has: a latch circuit which latches digital pixel data; a D/A converter which converts a latch output from the latch circuit into an analog video signal; an AMP which amplifies the analog video signal converted by the D/A converter; and a signal selection circuit which selects a signal line to which the analog video signal amplified by the AMP is supplied. The AMP has: an odd number of inverters which are cascade-connected; capacitor elements which are respectively connected between stages of the inverters and between an input terminal of the inverter on a first stage and an output terminal of the inverter on a last stage; a first power supply line which supplies a power supply voltage to the inverter on the first stage; and a second power supply line which supplies a power supply voltage to inverters other than the inverter on the first stage.

Abstract: The present invention, generally speaking, provides for high-efficiency power control of a high-efficiency (e.g., hard-limiting or switch-mode) power amplifier in such a manner as to achieve a desired modulation. In one embodiment, the spread between a maximum frequency of the desired modulation and the operating frequency of a switch-mode DC—DC converter is reduced by following the switch-mode converter with an active linear regulator. The linear regulator is designed so as to control the operating voltage of the power amplifier with sufficient bandwidth to faithfully reproduce the desired amplitude modulation wave-form. The linear regulator is further designed to reject variations on its input voltage even while the output voltage is changed in response to an applied control signal. This rejection will occur even though the variations on the input voltage are of commensurate or even lower frequency than that of the controlled output variation.

Abstract: A column driver for a graphics display has reduced power consumption by sharing power between upper and lower column amplifiers. The upper column amplifier operates over an upper supply range, while the lower column amplifier operates over a lower supply range. The upper and lower amplifiers have the substantially the same quiescent operating current such that the total operating current for the column drivers in the graphics display is reduced by a factor of two. Each column amplifier can be driven over half of the power-supply range such that lower voltage amplifiers may be employed for the column driver amplifiers.

Abstract: A method and apparatus is provided for detecting the output power of a power amplifier. The output power is detected by detecting the absolute values of the voltage and current at the output of the amplifier and mixing the detected voltage and current to generate a signal related to the output power.

Abstract: The invention involves systems and methods of providing energy to land-based telemetry devices wherein the energy storage and power conditioning system is comprised of an input power supply, an energy storage element, an output supply and a control system. The input power supply provides energy to the output power supply and charges the energy storage element. The energy storage element is comprised of one or more UltraCaps and supplies energy to the output power supply at times of peak need and when the primary energy source to the input power supply is removed. The control system adjusts the voltage supplied to the energy storage element by the input power supply according to changes in the ambient temperature to compensate for changes in the internal equivalent series resistance of the UltraCaps caused by the change in ambient temperature. The output power supply provides energy to the land-based telemetry device.

Abstract: A method and apparatus is provided for detecting the output power of a power amplifier. The output power is detected by detecting the absolute values of the voltage and current at the output of the amplifier and mixing the detected voltage and current to generate a signal related to the output power.

Abstract: A radio frequency (RF) generator apparatus for a plasma processing system that is resistant to nonlinear load mismatch conditions is provided. The apparatus includes an RF oscillator configured to generate an RF signal, an RF amplifier responsive to the RF signal to produce a VHF RF signal having sufficient power to drive a plasma chamber load, and a VHF-band circulator coupled to the amplifier and configured to isolate nonlinearities of the plasma chamber load from the amplifier.

Abstract: A transmission apparatus with reduced current consumption for a mobile terminal is disclosed. The transmission apparatus includes an automatic gain control (AGC) amplifier for AGC-amplifying an input baseband signal; an attenuator for attenuating an output signal of the AGC amplifier; a multiplier for multiplying an output signal of the attenuator by a carrier frequency signal to convert the signal into a radio frequency (RF) signal; a first filter for filtering an output signal of the multiplier; a drive amplifier for amplifying an output signal of the first filter; a second filter for filtering an output signal of the drive amplifier; a power amplifier for amplifying an output signal of the second filter; and an antenna. When output power of the mobile terminal is lower than predetermined maximum output power of the AGC amplifier, the output signal of the AGC amplifier is transmitted through the multiplier, the first filter and the antenna.

Abstract: An electrostatic loudspeaker requires a high voltage DC bias power supply to bias the stators and diaphragms of electrostatic speakers. A self biased power supply eliminates the need for an external power supply by deriving a high voltage bias from the stator AC signal voltages which have been rectified and run from a high voltage tap and/or through a voltage multiplier which has a voltage limiting means.

Abstract: In one embodiment, the present invention provides a radio frequency transmitter that may have a processor and a controller that reduce current consumption of the power amplifier of the radio frequency transmitter.

Abstract: The present invention, generally speaking, incorporates the power amplifier as a fundamental constituent of a modulator, using polar modulation techniques. Thus, it is possible to achieve the combination of precision signal generation (including envelope variations) along with high energy efficiency in combinations not possible heretofore. In accordance with one embodiment of the invention, a modulated radio (passband) signal generator produces high quality signals of general type, which specifically includes signals with varying envelopes. Signals are generated with high energy efficiency in the conversion of applied DC power to output RF signal power. The result is longer battery life for products such as mobile phone handsets. Dramatically improved efficiency also allows for a dramatic reduction (10 to 1 or greater) in the size of any required heatsink for the radio transmitter, which significantly lowers both cost and size.

Abstract: A method and a circuit for high-efficiency linear RF-power amplification over a wide range of amplitudes from zero to peak output includes a final RF-power amplifier operating at or near saturation, an RF driver amplifier, a high-level amplitude modulator for the final amplifier, preferably a high-level amplitude modulator for the driver amplifier, and a means for determining the supply-voltage input to the final amplifier and for controlling the amplitude of the drive. The means for determining the supply-voltage input and for controlling the amplitude acts so that the final amplifier drive varies from a minimum level to peak as the desired transmitter output varies from zero to peak. The transmitter is preferably of the envelope-elimination-and-restoration type or the envelope-tracking type.

Abstract: A system and method which generates amplified signals indicative of left and right stereo channels, and uses the signals to drive transducers for each of subwoofer, left stereo, and right stereo channels. The amplification circuitry is operable with a power supply having low peak current capability (i.e., low peak to average current rating) even when amplifying an input signal pair having highly correlated frequency components, since it spreads the peak current demands imposed on the power supply over a full cycle of each of the highly correlated frequency components. A series-connected pair of left and right channel transducers is driven by left and right channel power amplifiers of the amplification circuitry, and the subwoofer channel transducer is connected in parallel with this transducer pair so that all three transducers are driven by two power amplifiers, thus eliminating the need for a third power amplifier to drive the subwoofer channel transducer.

Abstract: A compensator for maintaining the amplification of one or more electronic signal amplifiers independent of fluctuations in the voltage and/or currents supplied to the amplifiers from voltage and/or current sources. A dummy amplifier is used which is substantially similar to the amplifier whose amplification is to be compensated and which is connected to the same sources. The changes in the output of the dummy amplifier are amplified and used to control a variable load which loads down, or alters, one or more of the voltage or current sources to the extent necessary to maintain the output of the dummy amplifier independent of variations in the voltage and/or current sources. Since the output of the dummy amplifier is maintained constant independent of supply variations, the outputs of the similar, electronic signal amplifiers also are maintained independent of supply variations.

Abstract: A noise isolation circuit is provided that consists of a dual function bypass which confines high-speed switching noise to the component or circuit which generates it and isolates the component or circuit from high-frequency noise transients which may be present on the ground and power supply busses. A local circuit ground is provided which is coupled to the system ground by sufficient impedance to force the dissipation of the noise signal in the local circuit or component generating the noise. The dual function bypass network couples high-frequency noise signals generated in the local component or circuit through a capacitor to the local ground while isolating the component or circuit from noise signals which may be present on the power supply busses or system ground. The network is an effective noise isolating system and is applicable to both high-speed analog and digital circuits.

Abstract: A circuit for supplying regulated first and second supply voltages to the amplifier/comparator of a recirculation of remainder analog to digital converter, comprises a series pair of transistors connected as emitter followers between unregulated voltage sources. Outputs of the emitter followers carry the regulated supply voltages and are applied to the supply terminals of the amplifier/comparator. A pair of diodes connected in series between the bases of the emitter followers establish the magnitudes of the two regulated supply voltages. The junction voltage between the two Zener diodes is controlled by a difference amplifier that in turn is responsive to an analog input voltage and the output of the amplifier/comparator. The output of the difference amplifier causes the regulated supply voltages to track a common mode signal component inherent in the converter and thereby improves component accuracy.

Abstract: Current having a density higher than a critical value is passed through a polycrystalline resistor doped with impurities at a concentration higher than a critical value to decreasingly correct the initial value of the resistance, thereby trimming the resistance value of the resistor. When the resistor is used in a semiconductor integrated circuit, the current is passed through the existing (not additional) terminals of the integrated circuit.

Abstract: An isolated signal conditioning circuit is provided whereby control or measurement circuitry is isolated from a load, such as a control instrument, through the use of an optically coupled isolation amplifier. The control or measurement signal is conditioned by the signal conditioning circuit so as to provide a signal to a load, such as a control instrument, which is compatible with the input requirements of the load.

Abstract: A remotely powered intermediate amplifier for communications transmission incorporates two sectional amplifiers and a filter circuit interconnecting the output of the first sectional amplifier with the input of the second sectional amplifier.

Abstract: A circuit permits the output voltage of an amplifier to be limited for certain ranges of its input voltage by causing the amplifier to saturate for said ranges of its input voltage by reducing the power supply.The invention is applicable, for example, to eliminating or levelling the components of a signal whose amplitude lies within a certain range, without affecting any other components.

Abstract: An amplifier circuit having an input adapted to receive a signal to be amplified from a signal source, at least two sets of combined amplifying transistors and associated power sources for the amplifying transistors, the two sets constituting first and second amplifying stages, a switching transistor for automatically switching the amplifying operation of the amplifier circuit from the first amplifying stage to the second amplifying stage depending upon the amplitude of the input signal to the amplifier and a load to which the amplifying transistors are connected in parallel.

Abstract: An electric amplifier useful for instance in simulators for strong electric signals, comprising several partial amplifiers so connected and voltage fed that they will amplify an interval each of the input voltage. Every partial amplifier comprises at least one amplification component and two gates, of which gates one is blocking those potentials applied to the component that are less than a given first value but is open for potentials exceeding said value while the other gate is open for potentials less than a given second value greater than said first value but is blocking the component for potentials exceeding said second value.

Abstract: The present application relates to electronic circuitry for the improved handling of electric signals, particularly to the amplification thereof. The present application discloses an integral-amplifier that has a much higher efficiency than corresponding prior-art circuits, and also discloses that, where so desired, intermodulation signals may be reduced to a negligible value.

Abstract: An imperfectly filtered d.c. operating voltage is applied to an electrode, such as the emitter electrode of an output transistor, an input signal being applied to another electrode, such as the base electrode of the transistor. The ripple component thereby induced at the collector electrode of this transistor is cancelled by adjusting to a value exactly equal thereto, the complementary ripple component of the d.c. operating voltage applied to the collector electrode.

Abstract: This invention relates to amplifiers for producing an accurate amplified version of a low voltage wave form. Specifically, the amplifier of the invention comprises independently fed first and second resistors connected to a common output which feeds a third resistor via a voltage to current converter, the other end of the third resistor being driven from the same point as the first resistor, the ratio of the resistances of the first and second resistors being made equal to the amplification required so that when the low voltage wave form is fed to the second resistor and a wave form approximating to the required output and of slightly higher voltage is fed to the first and third resistors, the voltage at the common output is proportional to the error in the approximated wave form and the voltage thereby developed across the third resistor by the voltage current converter is approximately equal to the error.

Abstract: There is disclosed an isolation amplifier having an input amplifier, an output amplifier, a transformer having primary and secondary windings, an alternator connected to the secondary winding of the transformer for alternately presenting a voltage and a high impedance to the secondary winding, a first switching device connected between the primary winding of the transformer and the output of the input amplifier for connecting the output of the input amplifier to the primary winding when the alternator presents a high impedance to the secondary winding and for disconnecting the output of the input amplifier from the primary winding when the alternator presents a voltage to the secondary winding and a second switching device connected between the secondary winding and the input to the output amplifier therefore connecting the input of the output amplifier to the secondary winding when the alternator presents a high impedance to the secondary winding and disconnecting the input of the output amplifier from the s

Abstract: In a direct coupling type power amplifier circuit comprising an input differential amplifier stage, a drive amplifier stage responsive to the output signal of the input differential amplifier stage dc-wise and ac-wise, and a push-pull output amplifier stage responsive to the output signal of the drive amplifier stage dc-wise and ac-wise, the input differential amplifier stage being supplied at one input electrode thereof with an input signal and at the other input electrode thereof with the output of the push-pull output amplifier stage through a negative feedback circuit network, the power amplifier circuit further comprises a bias circuit network for defining the dc bias current through the input differential amplifier stage and a delay circuit coupled between the bias circuit network and a power source voltage supply point.

Abstract: A bias circuit for a large pulse-width, broad-bandwidth radio-frequency avalanche device comprising a power supply coupled to the device through a bias line. The bias circuit includes a resistive network shunted across the bias line and ground to dampen spurious submicrowave oscillations.

Abstract: A circuit arrangement for the ungrounded transmission of signals through testing points in communication systems with the aid of high-frequency oscillations. The high-frequency oscillations are controlled on the one side of the testing point and are rectified on the other side of the testing point. The rectified signals are utilized to reproduce the signals again. A resonant circuit is adjusted to the high-frequency oscillations and is galvanically separately coupled to a high-frequency generator. The resonant circuit is also connected to a modulation circuit and to the input of the testing point. The resonant circuit is coupled inductively to a demodulation circuit which forms the output of the testing point.

Abstract: An input amplifier stage is isolated from the main body of an amplifier and instrument ground by a single transformer which provides both an energy path to the input stage and an amplifier signal path from the input stage using a modulated load technique. The secondary of the transformer, which is connected across the input amplifier, includes a rectifier and filtering components to provide a floating D. C. voltage supply.