Amplifiers inventions 09/06

20060208792 - Amplification system capable of reducing dc offset: An amplification system capable of reducing DC offset in a baseband signal, which has first and second differential output terminals, first and second low pass filters, and first and second amplifiers. The first low pass filter filters a first input signal to thus generate a first filtered signal. The first...

20060208793 - Class d amplifier: A D class amplifier of the invention generates a carrier signal Pct based on a master clock Φp without jitter, which is supplied to a PWM circuit. Using a digital PLL including a phase comparator, a loop filter and a carrier oscillator, the generated carrier signal Pct is synchronized with...

20060208794 - Class d amplifier: The invention is directed to a class D amplifier. According to the class D amplifier, sound data applied to an input terminal is supplied through a compensation circuit to a PWM circuit, from which a PWM signal is output. The PWM signal is converted to an analog signal through a...

20060208795 - Amplifier circuit and control method thereof: An amplifier circuit which is connected to a sensor and variably sets an amplification property and a control method thereof are disclosed, the circuit having the capability of restricting the influence of change with time and temperature change. The amplifier circuit 1, which receives, as an input, a detection signal...

20060208796 - Bias control for reducing amplifier power consumption and maintaining linearity: A method and apparatus for biasing an amplifying device whereby the bias current tracks the input power or the power level of a control signal to thereby efficiently match the bias current with needs of the amplifying device. This method and apparatus overcomes the drawbacks of the prior art by...

20060208797 - Integrated amplifier arrangement: A millimetric-wave amplifier arrangement comprises a first amplifier whose output is connected to one input of the second amplifier via an adjustable attenuator. Both amplifiers are integrated on a single substrate....

20060208798 - Compensation of nonlinearity introduced by dead time in switching output stage: A method of operating a class D amplifier output stage that compensates for nonlinearity introduced by a residual load current during the dead time in the switching of the output stage. The amplifier output stage includes an input, a gate driver circuit, two output transistors, an output, and a current...

20060208799 - Power amplifier circuitry having inductive networks: A method and apparatus is provided for use in power amplifiers for reducing the peak voltage that transistors are subjected to. A power amplifier is provided with first and second switching devices and an inductor connected between the switching devices. The switching devices are driven such that the switching devices...

20060208800 - Biasing stage for an amplifier: An amplifier biasing stage includes a transistor that provides a biasing signal for a complementary pair of field-effect transistors included in an output stage of an amplifier. The amplifier biasing stage also includes one resistive element connected to an emitter of the transistor, another resistive element connected to a base...

20060208801 - Method of controlling a variable gain amplifier and electronic circuit: The present invention relates to a method of controlling a variable gain amplifier having at least one semiconductor switch, the amplifier having a first gain when the semiconductor switch is in a first steady state and a first gate voltage is applied to the semiconductor switch, and the amplifier having...

20060208802 - Amplifier circuit with reduced temperature dependence of the gain: An amplifier circuit includes an amplifier input, an amplifier output, a control terminal for adjusting a gain of the amplifier circuit, and a feedback path between the amplifier output and the control terminal, wherein a variable-impedance means, the impedance of which depends on a temperature so that a variation of...

20060202749 - Mpas: The MPAS (Mini Musical Amplification System), is state of the art technology from two major companies. Roland Corporation and Apple/McIntosh Corporation integrated into my new invention called the MPAS. The unit can be interfaced with computers I order to download musical files, thereby giving the artist complete control and freedom...

20060202750 - Operational amplifier and method for canceling offset voltage of operational amplifier: An operational amplifier that cancels offset voltage while enabling its gain to be set to any value. The operational amplifier includes a first switch for short-circuiting the gates of two transistors in a first differential input unit. A capacitor is connected to the gates of two transistors in a second...

20060202752 - Controllable amplifier and its use: A controllable amplifier is disclosed. The amplifier includes two current paths which couple an input to an output of the controllable amplifier. Each current path has a respective transistor which is connected as source follower. One of the two current paths is designed to be controllable. It is thus possible...

20060202751 - Controllable amplifier and method for amplifying a signal: A controllable amplifier and a method for amplifying a signal dependent on an analog control signal (CTRL) are disclosed. A first and a second amplifier transistor are each arranged with an assigned cascode transistor in respective current paths. The amplification value of the amplifier transistors in the different current paths...

20060202753 - Differential driver circuit: A current-saving differential wideband driver circuit comprises a differential input amplifier for amplifying a differential input signal to produce a differential intermediate signal being comprised of a first intermediate signal and a second intermediate signal, a first transimpedance amplifier comprising a first inverting input, a first non-inverting input, and a...

20060202754 - Digital switching amplifier: There is provided a digital switching amplifier capable of enhancing an S/N ratio at the time of a small signal output and reducing current consumption and electromagnetic interference (EMI). The digital switching amplifier according to the present invention is provided with an integrator 11 for integrating an input signal, quantizer...

20060202755 - Gigabit ethernet transceiver with analog front end: Circuitry to remove switches from signal paths in integrated circuit programmable gain attenuators Programmable gain attenuators and programmable gain amplifiers commonly switch between signal levels using semi-conductor switches. Such switches may introduce non-linearities in the signal, By isolating the switches from the signal path linearity of the PGA can be...

20060202756 - Radio-frequency power amplifier apparatus and method of adjusting output power thereof: By using a radio-frequency power amplifier which turns off an Nth stage radio-frequency amplifying transistor when the level of radio-frequency output power falls below a predetermined value, it is possible to improve the linearity when the level of the radio-frequency output power is so low....

20060202757 - Power amplifier with integrated sensors: An amplifier circuit for amplifying radio frequency signals includes a radio frequency power amplifier to receive an input radio frequency signal and to output an amplified radio frequency signal; one or more sensors coupled to the radio frequency power amplifier to provide a closed-loop feedback signal; and a power sensor...

20060202758 - Amplifier with increased bandwidth and method thereof: An amplifier with increased bandwidth by current injection and a method thereof. The amplifier includes an input stage for receiving a first input signal, a load stage coupled to the input stage for generating a first output signal, a first current source coupled to the input stage for allowing a...

20060202759 - Transistor biasing independent of inductor voltage drop: A differential amplifier can include input transistors for receiving a differential input signal and an inductor connected to the input transistors. The inductor can protect a voltage supply from radio frequency in the differential input signal. The accuracy of this differential amplifier can be significantly improved by including a bias...

20060202760 - Controllable amplifier and the use thereof: A controllable amplifier amplifies a radiofrequency input signal on the basis of a control signal. A current path is formed between a supply potential connection and a reference potential connection. The current path includes an amplifier transistor and a cascode transistor, the cascode transistor being connected to the input for...

20060202761 - Amplifier unit and optical disc drive: An amplifier unit is provided, with which the need for manufacturing a photoelectric conversion IC in Bi-CMOS process is eliminated, and relatively low process cost of the photoelectric conversion IC is achieved. The input section of a buffer (the base of a transistor Q5) is connected with a plurality of...

20060202762 - Input amplifier with improved power supply rejection: An input amplifier for power amplifier control circuitry includes an input, an output, a power supply voltage, a ground, a differential amplifier and a double folded cascode and conversion stage. The differential amplifier is connected to the input, to the power supply voltage and to the ground. The differential amplifier...

20060202763 - Current mirror circuit: There is disclosed a current mirror circuit comprising a first transistor having a first electrode connected to a first potential, a second electrode connected to a second potential lower than the first potential, and a third electrode connected to a third potential higher than the second potential, a second transistor...

20060202764 - Bias circuit: The present invention has for its object to provide a bias circuit capable of handling multiple frequency bands, which has a low number of parts and can be miniaturized. As a solving means therefor, the bias circuit of the present invention comprises: a first reactance means 2 and a second...

20060202765 - Construction and use of preamps having discrete gain states: In one embodiment, the linear gain region of a preamp is widened by performing the following actions within the preamp: converting a received input current to a first voltage; in accordance with one of a plurality of discrete gain states, amplifying the first voltage to produce a second voltage; in...

20060202766 - Transimpedance amplifier with signal amplification circuit that performs power signal regulation: The transimpedance amplifier that performs signal amplification includes a first input that receives an input signal, a second input that receives a power signal, a third input that receives a control signal, and an output that generates an output signal. The transimpedance amplifier includes at least one signal amplification circuit...

20060197589 - Low-distortion tri-state switching amplifier: A switching amplifier includes a level shifting circuit for adjusting a voltage level of an original input signal to generate a first input signal and a second input signal. The first input signal is identical to the original input signal except for referring to a first reference level. The second...

20060197590 - Power amplifier and method for error correcting of output signals thereof: An amplifier includes a subtracting unit for generating an error signal according to an input signal and an output signal; a noise shaping unit for executing a noise shaping operation on the error signal to produce a noise-shaped signal; a pulse adjustment unit for generating a control signal according to...

20060197591 - Device and method for enhancing output current driving: A device and method for enhancing current driving are provided. The device comprises an operational amplifier, a monitor device, and an auxiliary output device. The monitor device is adopted to monitor whether the non-inverse input signal is close to a maximum or minimum voltage of an input source of the...

20060197592 - Variable gain amplifier: A variable gain amplifier includes a first, second, and third impedances, an OP amplifier, and a control circuit. The OP amplifier has a first input end and an output end; the output end for generating outputting an output signal. Two ends of the first impedances are coupled to an input...

20060197593 - Negative feedback system with an error compensation scheme: A negative feedback system includes a first summation module for receiving a system input and outputting a first summation output. A first forward module is coupled to the first summation module for receiving the first summation output and outputting a first forward output. A feedback module is coupled to the...

20060197594 - Protection of output stage transistor of an rf power amplifier: A protection method may prevent a load-mismatch-induced failure in solid-state power amplifiers. In an RF power amplifier, the load voltage standing-wave ratio results in very high voltage peaks at the collector of the final stage and may eventually lead to permanent failure of the power transistor due to avalanche breakdown....

20060197595 - Predistorter for power amplifier: A predistorter that linearizes the nonlinearity of a power amplifier in a system supporting a multimode and a multiband (frequency band). The predistorter includes a field-effect transistor, an impedance transform unit, a first inductor, a first capacitor, and a second capacitor. The field-effect transistor has a source connected to the...

20060197596 - Audio amplifier with high power and high efficiency: A Class D audio amplifier with output signals capable of being as high as the amplifier's supply voltage. The audio amplifier contains a comparator, a positive output stage, and a negative output stage. The output signal from the positive output stage and the output signal from the negative output stage...

20060197597 - Ultra low-frequency response, dc-blocked low-noise amplifier: An amplifier circuit is disclosed that allows for practical integrated circuit implementation of a dc-blocked, low-noise differential amplifier capable of amplifying ultra low-frequency signals and amplitudes ranging upwards of a few microvolts. DC-blocking capacitors having a capacitance value close to that of the effective input capacitance of the low-noise amplifier's...

20060197598 - Low voltage structure for gain boosting in high gain amplifiers: Reducing the bias voltage level required in a boost amplifier enhancing a gain of amplifier comprising first and second amplification stages. In an embodiment, the booster amplifier circuit contains a first transistor receiving both the bias voltage and the input signal respectively on the gate and source terminal and the...

20060197599 - Variable gain wideband amplifier: The invention relates to a feedback or feedforward type variable gain wideband amplifier. The variable gain wideband amplifier includes a feedback-type inversion amplifier circuit 310 for amplifying input Vin, a feedback-type non-inversion amplifier circuit 320 for amplifying input Vin, a power source circuit 330 for controlling the gain of the...

20060197600 - High frequency power amplifier circuit device: A multistage high frequency power amplifier-circuit device has a plurality of semiconductor amplification elements connected in a cascade. The circuit device is provided with a bias control circuit used to control the bias voltage or bias current of the output semiconductor amplification element in each stage so as to reduce...

20060197601 - Switching device for at least two voltages, corresponding electronic circuit and memory: A device for switching voltages includes at least two branches each allowing the voltage from a power source to be switched to a single output. Each of the said branches includes at least two transistors, of which at least one is a protective transistor with a dual function: protecting the...

20060197602 - Semiconductor indicator for voltage diagnostics in power amplifiers: A semiconductor indicator for quantitatively diagnosing voltage conditions in high power transistor devices is provided. The semiconductor indicator includes a first transistor and a second transistor, where an electrically active periphery of the second transistor is less than an electrically active periphery of the first transistor. The transistors are thermally...

20060197589 - Low-distortion tri-state switching amplifier: A switching amplifier includes a level shifting circuit for adjusting a voltage level of an original input signal to generate a first input signal and a second input signal. The first input signal is identical to the original input signal except for referring to a first reference level. The second...

20060197590 - Power amplifier and method for error correcting of output signals thereof: An amplifier includes a subtracting unit for generating an error signal according to an input signal and an output signal; a noise shaping unit for executing a noise shaping operation on the error signal to produce a noise-shaped signal; a pulse adjustment unit for generating a control signal according to...

20060197591 - Device and method for enhancing output current driving: A device and method for enhancing current driving are provided. The device comprises an operational amplifier, a monitor device, and an auxiliary output device. The monitor device is adopted to monitor whether the non-inverse input signal is close to a maximum or minimum voltage of an input source of the...

20060197592 - Variable gain amplifier: A variable gain amplifier includes a first, second, and third impedances, an OP amplifier, and a control circuit. The OP amplifier has a first input end and an output end; the output end for generating outputting an output signal. Two ends of the first impedances are coupled to an input...

20060197593 - Negative feedback system with an error compensation scheme: A negative feedback system includes a first summation module for receiving a system input and outputting a first summation output. A first forward module is coupled to the first summation module for receiving the first summation output and outputting a first forward output. A feedback module is coupled to the...

20060197594 - Protection of output stage transistor of an rf power amplifier: A protection method may prevent a load-mismatch-induced failure in solid-state power amplifiers. In an RF power amplifier, the load voltage standing-wave ratio results in very high voltage peaks at the collector of the final stage and may eventually lead to permanent failure of the power transistor due to avalanche breakdown....

20060197595 - Predistorter for power amplifier: A predistorter that linearizes the nonlinearity of a power amplifier in a system supporting a multimode and a multiband (frequency band). The predistorter includes a field-effect transistor, an impedance transform unit, a first inductor, a first capacitor, and a second capacitor. The field-effect transistor has a source connected to the...

20060197596 - Audio amplifier with high power and high efficiency: A Class D audio amplifier with output signals capable of being as high as the amplifier's supply voltage. The audio amplifier contains a comparator, a positive output stage, and a negative output stage. The output signal from the positive output stage and the output signal from the negative output stage...

20060197597 - Ultra low-frequency response, dc-blocked low-noise amplifier: An amplifier circuit is disclosed that allows for practical integrated circuit implementation of a dc-blocked, low-noise differential amplifier capable of amplifying ultra low-frequency signals and amplitudes ranging upwards of a few microvolts. DC-blocking capacitors having a capacitance value close to that of the effective input capacitance of the low-noise amplifier's...

20060197598 - Low voltage structure for gain boosting in high gain amplifiers: Reducing the bias voltage level required in a boost amplifier enhancing a gain of amplifier comprising first and second amplification stages. In an embodiment, the booster amplifier circuit contains a first transistor receiving both the bias voltage and the input signal respectively on the gate and source terminal and the...

20060197599 - Variable gain wideband amplifier: The invention relates to a feedback or feedforward type variable gain wideband amplifier. The variable gain wideband amplifier includes a feedback-type inversion amplifier circuit 310 for amplifying input Vin, a feedback-type non-inversion amplifier circuit 320 for amplifying input Vin, a power source circuit 330 for controlling the gain of the...

20060197600 - High frequency power amplifier circuit device: A multistage high frequency power amplifier-circuit device has a plurality of semiconductor amplification elements connected in a cascade. The circuit device is provided with a bias control circuit used to control the bias voltage or bias current of the output semiconductor amplification element in each stage so as to reduce...

20060197601 - Switching device for at least two voltages, corresponding electronic circuit and memory: A device for switching voltages includes at least two branches each allowing the voltage from a power source to be switched to a single output. Each of the said branches includes at least two transistors, of which at least one is a protective transistor with a dual function: protecting the...

20060197602 - Semiconductor indicator for voltage diagnostics in power amplifiers: A semiconductor indicator for quantitatively diagnosing voltage conditions in high power transistor devices is provided. The semiconductor indicator includes a first transistor and a second transistor, where an electrically active periphery of the second transistor is less than an electrically active periphery of the first transistor. The transistors are thermally...