53 results about "Wideband amplifiers" patented technology

High-speed silicon CMOS circuits and high-power AlGaN/GaN amplifiers are integrated on the same wafer. A thin layer of high resistivity silicon is bonded on a substrate. Following the bonding, an AlGaN/GaN structure is grown over the bonded silicon layer. A silicon nitride or a silicon oxide layer is then deposited over the AlGaN/GaN structure. Following this, a thin layer of silicon is bonded to the silicon nitride/silicon oxide layer. An area for the fabrication of AlGaN/GaN devices is defined, and the silicon is etched away from those areas. Following this, CMOS devices are fabricated on the silicon layer and AlGaN/GaN devices fabricated on the AlGaN/GaN surface.

The invention relates to the fields of quantum secret communication, weak ultrared detection, and the like, and provides an impulse gate-control low-pass filtering ultrared single-photon detector. Theimpulse gate-control low-pass filtering ultrared single-photon detector comprises an impulse gate-control power source, an In-Ga-As-In-P avalanche photodiode circuit, a DC voltage baising circuit, alow-pass filter, a high-speed wideband amplifier, a ultra-high-speed comparator and a counter, wherein gigahertz (GHz) impulse signals output by the impulse gate-control power source are used as gatecontrol signals of the In-Ga-As-In-P avalanche photodiode circuit, and spike noise signals caused by the junction capacitance differential effect of In-Ga-As-In-P avalanche photodiodes by the low-passfilter are used for filtering in a low-pass mode. The gigahertz impulse gate-control low-pass filtering ultrared single-photon detector solves the problem of spike noise interference in the prior art, increases the detection sensitivity of the avalanche signals and can be used for detecting GHz high-speed ultrared photon.

Doherty and distributed amplifier (DA) designs are combined to achieve, wideband amplifiers with high efficiency dynamic range. A modified Doherty amplifier includes a wideband phase shifter providing first and second outputs, a main amplifier coupled to the first output, an auxiliary amplifier coupled to the second output, and a wideband combining network combining the outputs in phase. A multi-stage DA has a main output and a termination port, and a phase delay module and transforming network allowing power at the termination port to be combined in phase with power at the main output. In one combination, one or more stages of the DA may comprise a Doherty amplifier. In another combination, a modified series-type Doherty amplifying system is achieved by cascading main and auxiliary DAs. In any combination, Doherty topology may include a bias control module.

The invention relates to the fields of quantum secret communication, weak ultrared detection, and the like, and provides a ultrared single-photon detector. The ultrared single-photon detector comprises a sine-wave gate-control power source, an In-Ga-As-In-P avalanche photodiode circuit, a DC voltage baising circuit, a semiconductor temperature-control circuit, a low-pass filter, a high-speed wideband amplifier, a ultra-high-speed comparator and a counter, wherein sine waves which have the frequency of gigahertz (GHz) and are output by the sine-wave gate-control power source are used as gate control signals of the In-Ga-As-In-P avalanche photodiode circuit, and spike noise caused by junction capacitance differential effect for the low pass filter is used for filtering in a low-pass mode. The gigahertz sine-wave gate-control low-pass filtering ultrared single-photon detector solves the problem of spike noise interference in the prior art, increases the detection sensitivity of avalanchesignals and is used for detecting GHz high-speed ultrared photon.

Current-controlled CMOS (C3MOS) fully differential integrated wideband amplifier/equalizer with adjustable gain and frequency response without additional power or loading. A novel approach is presented by which adjustable amplification and equalizer may be achieved using a C3MOS wideband data stage. This may be referred to as a C3MOS wideband data amplifier/equalizer circuit. This employs a wideband differential transistor pair that is fed using two separate transistor current sources. A switchable RC network is communicatively coupled between the sources of the individual transistors of the wideband differential transistor pair. There are a variety of means by which the switchable RC network may be implemented, including using a plurality of components (e.g., capacitors and resistors connected in parallel). In such an embodiment, each component may have an individual switch to govem its connectivity in the switchable RC network thereby allowing a broad range of amplification and equalization to be performed.

The invention provides an optical detector, a component of the optical detector, and a photoelectric front-end amplifier circuit, belonging to the technical field of four-quadrant photoelectric detection application. The photoelectric front-end amplifier circuit comprises three-stage structures including a low-noise front-end trans-impedance amplifier, an intermediate-stage voltage amplifier and an output buffer amplifier; and the three-stage circuits are coupled through direct current to form a wideband amplifier. The optical detector, the component of optical detector, and the photoelectric front-end amplifier circuit disclosed by the invention have the benefits that: the circuit structure is compatible with the existing detector process; single integration can be carried out; and the four-quadrant photoelectric detector is small in volume, low in power consumption and cost, and high in reliability.

The invention discloses a low-noise amplifier circuit. The low-noise amplifier circuit comprises an input coupling network, a first amplifier element, a first biasing unit, a second amplifier element and a second biasing unit, wherein a front-end circuit and the rear-end first amplifier element are connected by the input coupling network; the first amplifier element is connected with the input coupling network and used for amplifying an input signal; the first biasing unit is connected with the first amplifier element, and used for controlling a quiescent operating point of the first amplifier element in a linear amplifying zone; the second amplifier element is connected with the first amplifier element and used for amplifying an output signal of the first amplifier element; the second biasing unit is connected with the second amplifier element, and used for controlling a quiescent operating point of the second amplifier element in the linear amplifying zone. According to the technical scheme, a high-input impedance wideband and low-noise amplifier is adopted, the wideband amplifier realizes pre-amplifying decoupling through high-input impedance, provides a wider frequency band, provides a low noise coefficient, and supports the application of multi-nuclear magnetic resonance imaging; the design complexity is reduced, the circuit is convenient to debug, and element materials are saved.

The present invention discloses a high-gain broad-band amplifier circuit that has temperature compensation and consists of a traditional Darlington transistor based routine radio frequency broad band amplifier circuit, a diode 13 that is connected with the dividing resistor 21 in the traditional Darlington transistor based routine radio frequency amplifier circuit, the collector of the diode 13 is connected with the base electrode of the transistor 11 in the traditional Darlington transistor based routine radio frequency broad band amplifier circuit, the collector 13 of the diode 13 is connected with the base electrode of itself, the emitter of the diode 13 is connected with the emitter of the transistor 11 through the dividing resistor 24 and the ballasting resistor 23. The present invention has the advantages of reducing the negative feedback of the amplifier circuit, improving the gain of the amplifier circuit, reducing the changes of the base electrode circuit that are caused by voltage drop changes of the transistor 11 and transistor 12 and gaining the function of compensating the temperature of the circuit.

Provided is a wideband amplifier which can provide an increased operation bandwidth without being limited by manufacturing process. A source follower circuit having a MOS transistor and constant-current supplies is provided in parallel to a MOS transistor serving as an amplifier of the input stage. Furthermore, the sources of the MOS transistor serving as the output of the source follower circuit are connected to the output nodes of the input stage amplifier via phase compensation capacitors, respectively. This configuration provides an increased phase allowance to the wideband amplifier, thereby providing an improved operation bandwidth without being limited by the manufacturing process employed.

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 non-inversion amplifier circuit 320 and a load circuit 340 connected between a junction of output terminals of the inversion and non-inversion amplifier circuits 310 and 320 and power voltage potential VDD to control the gain of the amplifier circuits 310 and 320. The variable gain wideband amplifier of the invention is feedforward type, and outputs signals from the inversion and non-inversion amplifier circuits 310 and 320 via a single output terminal in order to attenuate third order intermodulation frequency IM3 generated from the amplifier circuits 310 and 320. Then, predetermined frequencies f1 and f2 included in the input signal are amplified.

The invention discloses a wideband amplifier circuit of a Darlington structure. The wideband amplifier circuit comprises a first-stage amplification circuit, a second-stage amplification circuit and a phase regulating circuit. The first-stage amplification circuit comprises a first triode, and the base of the first triode is the signal input end of the wideband amplifier circuit. The second-stage amplification circuit comprises a second triode and a third triode. The emitter of the second triode is connected with the collector of the third triode, the base of the second triode is connected with direct-current bias voltages, and the emitter of the third triode is grounded. The emitter of the first triode is connected with the base of the third triode, and the collector of the first triode is connected with the collector of the second triode and serves as the signal output end of the wideband amplifier circuit. The phase regulating circuit is used for adjusting the current phase of the collector of the first-stage amplification circuit. One end of the phase regulating circuit is grounded, and the other end of the phase regulating circuit is connected with the connecting end of the emitter of the first triode and the base of the third triode.

A wideband amplifier is provided with at least one erbium-doped fiber, for use in a wavelength division multiplexing optical communication system that performs transmission/receipt of wavelength-division-multiplexed optical signals through at least one optical fiber. The wideband amplifier comprises an erbium-doped fiber, pumped by a first pump light that pumps erbium ions and a second pump light that induces a Raman amplification, that amplifies the optical signals, a first pumping light source that outputs a predetermined wavelength of first pump light such that the erbium ions are pumped from the erbium-doped fiber, a first wavelength selective coupler that passes through optical signals amplified at the erbium-doped fiber and that inputs the first pump light into the erbium-doped fiber, a second pumping light source that outputs a predetermined wavelength of the second pump light such that a Raman pumping is performed of the erbium-doped fiber, and a second wavelength selective coupler that passes through optical signals amplified at the erbium-doped fiber and that inputs the second pump light into the erbium-doped fiber.

The present invention provides a laser transmitting circuit, a laser receiving circuit, a distance calculation circuit and devices thereof. The laser transmitting circuit comprises an energy storage capacitor, a laser transmitting tube, an MOS switch circuit and an MOS switch driving circuit. The laser receiving circuit comprises a laser receiving tube, a first low-noise triode, a second low-noise triode and a low-noise wideband amplifier. The distance calculation circuit comprises a singlechip, a programmable logic circuit, a clock source and an echo identification circuit. The present invention further provides a low-voltage power circuit that provides a reverse polarity protection to an external power supply without additional diode connected in reverse polarity. According to the technical solutions provided by the present invention, the measurement range and precision of a semiconductor laser rangefinder can be improved effectively.

A wideband amplifier having an amplifier input terminal and an amplifier output terminal includes at least one transistor coupled to the amplifier input terminal and an impedance element coupled between the amplifier input terminal and the amplifier output terminal. A feedback signal is transmitted between the amplifier output terminal and the amplifier input terminal by way of the impedance element wherein the feedback signal varies in accordance with changes in an impedance of the impedance element so as to peak a frequency response of the amplifier.

An output signal SHS is secondarily amplified by a high-frequency amplifier AMP3 and an output signal SHR is secondarily amplified by an AMP4 for which high-frequency side amplitude reducing means is taken. In this case, the AMP4 has small gain of a high-frequency region and its output SHR-2 is reduced in amplitude. However, a high-frequency noise has a frequency higher than that of a carrier wave SH and the amplitude of a noise NzB becomes smaller. The other output signal SHS is directly amplified by the wideband amplifier AMP3. The width of an SHS-2 and the width of the SHR-2 are adjusted by amplitude adjusting means throughout the whole region and then mutually added by both signals addition amplifying means again so that the amplitude of the output signal SHS is adjusted to the SHR-2, and a predetermined threshold value is set to extract the noises.