Matches 301 - 350 out of 385 < 1 2 3 4 5 6 7 8 >
Match Document Document Title
5886576 Electrical power amplifier for continuous cardiac output monitoring  
A continuous cardiac output monitor a general-purpose monitoring console with local display and communication facilities, and a module removably interfacing with the console to configure the latter...
5847602 Method and apparatus for linearizing an efficient class D/E power amplifier using delta modulation  
A delta-modulated magnitude amplifier is used to amplify the magnitude component of an RF power amplifier that employs envelope elimination and restoration. The delta-modulated amplifier introduces...
5789975 Analog signal amplifier and audio signal amplifier  
An input limiting circuit limits the maximum signal voltage value of input signal voltage supplied from a signal source through an input terminal. A power amplifying circuit converts the signal...
5777512 Method and apparatus for oversampled, noise-shaping, mixed-signal processing  
A signal processing circuit is provided which includes a frequency selective network in a feedback loop for noise shaping purposes. A sampling analog-to-digital converter in the feedback loop...
5672998 Class D amplifier and method  
A Class D (audio) amplifier and method in which an input signal for the amplifier is pulse width modulated outside of the amplifier's feedback loop, and in which the pulse width modulated input...
5617058 Digital signal processing for linearization of small input signals to a tri-state power switch  
An all digital switching amplifier wherein linearization of the power switch is accomplished solely by using three states. A small, fixed width, bi-state compensating carrier waveform is added to...
5535438 Phase linear class E amplifier for a satellite communication terminal which communicates with a low earth orbiting satellite  
A low earth orbiting satellite communication terminal includes a data signal generator, a modulator, and a class E switching amplifier. The modulator converts a data signal from the data signal...
5434540 High efficiency power amplifier  
In a high efficiency F-class amplifier, output current may be reduced to cause distortion of the current, or deterioration of high efficiency operation of the amplifier, when an instantaneous...
5422597 Means and method of enhancing signal resolution and dynamic range extension in a pulse width modulation amplifier  
An amplifier (1) used with a pulse width modulated signal which improves the efficiency of a low level input signal comprises two or more switching devices (7,9) with common source/drain or...
5345165 Frequency-stabilized two-state modulation using hysteresis control  
A two-state modulation system includes a hysteretic comparator with variable thresholds, a two-state processor and an integrating element. A summing circuit combines a signal coupled from the...
5345189 Vectorial signal combiner for generating an amplitude modulated carrier by adding two phase modulated constant envelope carriers  
A circuit for combining first and second signals having the same frequency. The signals have a relative phase shift, 2a(t). The circuit generates a signal that is proportional to the sum or...
5343161 Power amplifier apparatus  
A power amplifier apparatus having an operational amplifier which works as a PWM (pulse width modulation) amplifier as well as an analog amplifier according to an input signal level to miniaturize...
5247264 Combining circuit for Class-E RF power amplifiers  
A combining circuit for Class-E RF power amplifiers includes a transformer for each power amplifier to be combined, the respective secondaries of the transformers being connected in series to the...
5218315 Switching amplifier  
An improved digital switching amplifier is disclosed. The amplifier utilizes a low-pass filter at the input of the switching comparator to give an improved signal to noise ratio at the final...
5214392 Multilayered ceramic type electromagnetic coupler apparatus  
A multilayered ceramic electromagnetic coupler apparatus includes coils formed on ceramic substrates. The coils are laminated and have insulting layers between the ceramic substrates, a modulator...
5200707 Amplifier with multiple switched stages and noise suppression  
An amplifier has at least several stages activated only to one of two bi-level states controlled in response to the value of an input source exceeding a threshold for each stage. Each stage has a...
5187580 High power switch-mode radio frequency amplifier method and apparatus  
Disclosed are both methods and a circuit to achieve powers of many kilowatts in radio frequency amplification using a switch mode amplifier in a new class of operation. In operation the invention...
5170132 Chopper amplifier circuit for the supply of a current proportional to a voltage  
The disclosure relates to fast amplification circuits that are designed to provide an output current of some amperes, proportional to an input voltage, and have a frequency spectrum that may go...
5163174 Power amplifier  
A power amplifier for amplifying analog input signals includes one or a plurality of amplifier modules which are connected in series on their output sides, which preferably each include a double...
5160896 Class D amplifier  
A hysteresis-type pulse width modulator for a class D audio amplifier converts an input voltage into a pulse width modulated waveform. The width of the pulses is related to the input voltage...
5118997 Dual feedback control for a high-efficiency class-d power amplifier circuit  
A dual feedback control system for a Class-D power circuit maximizes efficiency by controlling the magnitude and phase angle of the resonant load circuit using two separate feedback loops. The...
5115203 Digital power amplifier  
A wideband high efficiency amplification system for amplifying radio frequency signals to high power levels. The system includes components adapted for generating an RF carrier signal having a...
5113145 Power amplifier for feeding an inductance with switched transistors  
Switched transistors (T1 . . . through T4 . . .) are arranged in a bridge circuit such that a plurality of transistors (T1 . . . through T4 . . .) are connected in parallel in every bridge branch....
5099203 Power amplifier having multiple switched stages and method of operating same  
A power amplifier for a plate load of an AM, RF transmitter includes plural switching stages each powered by a DC source. Each stage is switched from non-sourced to saturation in response to the...
5077540 Minimum pulse width switching power amplifier  
A minimum pulse width switching power amplifier utilizes digital logic for generating a control pulse having a pulse width at least as large as a fixed minimum period of time when a base control...
5063332 Feedback control system for a high-efficiency class-D power amplifier circuit  
A closed-loop control system for a Class-D power amplifier circuit, having a variable output resonant circuit impedance, maintains high-efficiency operation by using the phase angle between the...
5023566 Driver for a high efficiency, high frequency Class-D power amplifier  
A driver circuit for a voltage-switching, high frequency Class-D power amplifier provides an input sinewave power signal and controls the transition time between switching the two active devices...
RE33333 Digital audio amplifier having a high power output level and low distortion  
A digital amplifier having a modulator for transforming the analog audio input signal into two complimentary trains of pulse width modulated signals for driving the power switches, which modulator...
4764734 Class SM power amplifier  
A class SM amplifier is provided having a threshold circuit with a plurality of threshold levels for generating a plurality of threshold signals. In response to an input signal passing a particular...
4748421 Enhanced class SM power amplifier  
A class SM amplifier is provided having a threshold circuit with a plurality of threshold levels for generating a plurality of threshold signals. In response to an input signal passing a particular...
4743858 R. F. power amplifier  
An r.f. power amplifier, typically a high efficiency, class E amplifier in which a reactive load circuit (18) is connected to a semiconductor switching device (10), the load circuit being designed...
4727874 Electrosurgical generator with high-frequency pulse width modulated feedback power control  
A pulse width modulation technique regulates the output power of each cycle of a radio frequency surgical signal of an electrosurgical generator. The delivered power of the surgical signal is...
4683439 Digitally driven switching power amplifier system  
A digital power amplifier system includes means providing a signal having predetermined characteristics is digitally synthesized and applied as input signals to a digital symmetrical pulse width...
4673887 Digital driver for fixed power amplifier  
A digital power amplifier system features an analog signal which is converted to a corresponding digital signal and is, in turn, applied as input signals in a digital binary format to a digital...
4667144 High frequency, high voltage MOSFET isolation amplifier  
A MOSFET isolation amplifier apparatus to allow stable high frequency linear operation of MOSFET power stages and to provide precise regulation of a load current through a magnetic yoke load....
4649467 High efficiency MOSFET sine wave generator  
A high efficiency MOSFET sine wave generator is provided using the class D pulse width modulation principle. A triangle wave at f 0 is compared to a variable amplitude sinusoid at about 1/10 f 0 ...
4628275 Efficient power amplifier for high capacitive devices  
An efficient power amplifier for high-capacitive device C2 in load string 10. The load string 10 includes a reference capacitor C3, a resistor R1, and an inductor L1. A large capacitor C1 is...
4608541 Isolation amplifier  
The invention comprises an isolation amplifier including an input circuit and an output circuit coupled through an isolation transformer. A switching type balanced modulator modulates a square wave...
4446440 Dual mode amplifier  
An apparatus amplifies a signal in two different modes. The apparatus amplifies the signal in a linear mode when the voltage of the signal is much less than the voltage of the power source, and in...
4441081 Switching power driving circuit arrangement  
This dual operating mode switching power driving circuit arrangement comprises an amplifying circuit of conventional form which is operated substantially as a Class A feedback amplifier in a...
4439738 Class D pulse width modulated amplifier  
An arrangement for improving the performance of Class D pulse width modulated amplifiers which comprises circuitry for short circuiting turns on the output transformer during intervals between...
4390849 Audio power amplifier with class-D push-pull output stage  
An audio power amplifier with class-D push pull output stage is disclosed using a "mixture" of pulse-width modulation and pulse-amplitude modulation and driving the class-D push pull output stage...
4390846 Power amplifier connection  
A power amplifier connection comprises a switching amplifier and a proportional amplifier. The output signal from the switching amplifier and the output signal from the proportional amplifier are...
4383203 Circuit means for efficiently driving an electrodeless discharge lamp  
In an electrodeless discharge lamp of the type including an ionizable medium within a sealed envelope capable of emitting radiant energy when subjected to a radio frequency field, an oscillator for...
4369409 Low-frequency power amplifier  
A compact and inexpensive LF power amplifier is disclosed. A plurality of pulse trains which are phase shifted relative to each other are width-modulated by an input LF signal. The modulated pulse...
4347481 Pulse width modulated signal amplifier  
A pulse width modulated signal amplifier includes a first DC voltage source having first and second terminals, first and second switching transistors each having a control electrode, the main...
4336615 Linear loading for PWM filter  
An AM broadcast transmitter uses a PWM modulator that requires a pulse width filter. It has been found that the filter load varies over the modulation cycle resulting in distortion. To overcome...
4326170 High power and/or high voltage switching operational amplifier  
There is disclosed a high power and/or high voltage switching operational amplifier arrangement having a comparator with a first input for a low frequency AC signal. The output of the comparator is...
4240036 Linearized three-state switching amplifier  
A pulse width modulated switching amplifier is provided for amplifying an analog signal. Means is provided for producing positive and negative signals representative of positive and negative...
4182992 Pulse width modulated signal amplifier  
A pulse width modulated signal amplifier includes first and second switching transistors and a diode which are connected in series across a DC power source and in the forward direction with respect...
Matches 301 - 350 out of 385 < 1 2 3 4 5 6 7 8 >