76results about How to "Low noise characteristics" patented technology

A voltage regulator includes a linear mode regulator having a high pass filter circuit connected between its output and an output node, and a switch mode regulator having an low pass filter circuit connected between its output and the same output node. The high pass filter passes high frequency AC current provided by the linear mode regulator to the output node and reduces the low frequency AC and DC currents to substantially zero, and the low pass filter prevents the high frequency AC current produced by the linear mode regulator from being drawn by the switch mode regulator and passes the low AC and DC currents provided by the switch mode regulator to the output node. Thus, the present regulator offers the high response speed and low noise of a linear mode regulator, and the high power efficiency and large continuous output current capability of a switch mode regulator.

A modulated laser light detector that converts laser light energy into electrical signals which exhibit a frequency that is substantially the same as the laser light modulation frequency, in which these signals allow the detector unit to determine a position where the laser light is impacting upon a photodiode array. A synchronous rectifier circuit is provided which, by use of a phase locked loop, converts a full-wave analog signal representative of the modulated laser energy into a half-wave analog signal, which is filtered and demodulated to generate a DC level that is indicative of the strength of the received laser light energy. At least two channels of these signals are used to determine the impacting position of the laser light energy.

A low noise amplifier is provided for the receiver of a wireless communications system. The amplifier incorporates an image rejection function by incorporating a notch filter formed by an inductor and capacitor connected at a node between two active elements of the amplifier. The amplifier also incorporates a gain control function by adding a further active element connected to, on one hand, a node between the inductor and capacitor and, on the other hand, a voltage supply. A gain control signal is connected to the control input of the further active element has an input connected to a feedback lead of the receiver to provide the gain control.

The invention discloses a load self-adaptation variable-frequency multi-connection heat pump system and method for controlling compressor frequency. The system comprises indoor units, outdoor units, a frequency control device, and pipes connecting the indoor units and the outdoor units. Each indoor unit is provided with an indoor heat exchanger for indoor heat exchanger. Each outdoor unit is provided with a compressor. The frequency control device is used for controlling compressor frequency. The frequency control device is also used for acquiring actual measured return air temperature of the operating indoor units when number of the operating indoor units is unchanged and intaking temperature of indoor units indicating indoor load changes. Heat exchange target parameters are determined according to difference of set indoor temperature and actual measured return air temperature. Actual measured heat exchange parameters corresponding to the heat exchange target parameters are acquired, and the difference of the actual measured heat exchange parameters and the heat exchange target parameters is applied to a preset frequency control function to control the frequency of the compressors. By the system and the method, frequency control precision under refrigerating work conditions can be increased.

A highly sensitive optical sensor element, and a switch element such as a sensor driver circuit are formed on the same insulating substrate by using an LTPS planar process to provide a low cost area sensor (optical sensor device) incorporating the sensor driver circuit and the like or an image display device incorporating the optical sensor element. As an optical sensor element structure, one electrode of the sensor element is manufactured with the same film of the polycrystalline silicon film that is an active layer of the switch element constituting a circuit. A photoelectric conversion unit for performing photoelectric conversion is made of an amorphous silicon or a polycrystalline silicon film of an intrinsic layer. A structure in which the amorphous silicon of the photoelectric conversion unit and the insulating layer are sandwiched between two electrodes of the sensor element is adopted.

Provided is a phase frequency detector for use in a phase locked loop (PLL) or a delay locked loop (DLL), the phase frequency detector including: an UP signal output unit having a first stage operated according to a reference clock delayed by a predetermined time and a reset signal, a second stage operated according to the reference clock and an output of the first stage, and an inverter for inverting an output of the second stage; a DOWN signal output unit having: a first stage operated according to an outer clock delayed by a predetermined time and the reset signal, a second stage operated according to the outer clock and an output of the first stage, and an inverter for inverting an output of the second stage; and a logic gate logically combining the output of the second stage of the UP signal output unit and the output of the second stage of the DOWN signal output unit to generate the reset signal, thereby a phase range of the input signal with which an effective control signal can be obtained is wide so that low power consumption and low noise characteristics can be obtained due to fast phase lock, low power consumption of a dynamic logic, and fast signal transmission.

The present invention discloses a wavelength-division multiplexing passive optical network (WDM-PON) capable of high-bandwidth transmission for optical signals by using modulation format having high spectral efficiency. The WDM-PON according to the present invention provides a larger capacity and higher bandwidth transmission economically (at lower costs) by using a modulation format where spectral efficiency (a transmission bit number per a unit band width) is high, while using a low noise part of a light source.

A semiconductor device which can avoid increase of a conduction loss of an IGBT, secure a low noise characteristic and also reduce a switch loss. The switching device is of a trench gate type, in which a drift n⁻ layer 110 is exposed to its main surface to a floating p layer 126 and to trench gates. In other words, the floating p layer 126 is provided within the drift n⁻ layer 110 to be spaced from the trench gates.

An interactive combination of Phoswich detector array (PDA) and differential absorption lidar (DIAL) is proposed to trace the unknown radioactive plumes released into the atmosphere from a reactor stack, containment of the nuclear power plants, radioisotope separation laboratories, reprocessing plants or the uranium conversion facilities. The hybrid system represents a powerful technique for the prompt identification and quantification of the effluents with various radionuclide contents to determine the corresponding external dose rate accordingly.

Disclosed herein is a low noise amplifier having both ultra-high linearity and a low noise characteristic and a radio receiver including the low noise amplifier. The low noise amplifier includes a first main transistor unit, a first auxiliary transistor unit, and an optimum noise and input impedance matching capacitor. The first main transistor unit includes a first NMOS transistor and a first PMOS transistor configured to form a complementary common source amplifier, a feedback-type resistor connected between drains of the first NMOS transistor and the first PMOS transistor and configured to generate biases to the two transistors, and bias resistors connected to bodies of the first PMOS transistor and the first NMOS transistor. The first auxiliary transistor unit includes transistors connected to the two transistors. The optimum noise and input impedance matching capacitor is connected to output terminals of the first main transistor unit and the first auxiliary transistor unit.

The invention relates to a laser phase lock device and method. The device comprises a mode-locking laser device, an electric signal extraction unit, a microwave reference source, a foundamental wave phase discrimination unit, a harmonic wave phase discrimination unit, a first changeover switch, a second changeover switch, a loop control unit and an off-loop digital monitoring unit, wherein the mode-locking laser device and the electric signal extraction unit are sequentially connected, the foundamental wave phase discrimination unit and the harmonic wave phase discrimination unit are connectedwith the electric signal extraction unit and the microwave reference source, and the off-loop digital monitoring unit is connected between the loop control unit and the mode-locking laser device. Thedevice has a remarkable low-noise characteristic, the synchronous precision can reach the tens-of-femtosecond order, and the device also has high stability and is suitable for working occasions wherethe laser device needs to continuously run for a long time.

A multi-layer printed circuit board having a low noise characteristic, the multi-layer printed circuit board includes at least one circuit layer; at least one isolation line for dividing the at least one circuit layer into at least two areas, the at least one isolation line forming an open pattern and the at least one isolation line extendedly forming a long neck line into the at least one area; and at least one capacitor placed at one side of the opening of the open pattern in any one of the areas.

A reverse current detection apparatus determines whether an electrical conduction control to a motor coil of a motor is in a predetermined state based on a timing signal representing a timing at which to conduct a source current or a sink current through the motor coil and a control signal for a half bridge in a power stage, and compares the output voltage of the power stage with a threshold value, so as to detect the presence/absence of a reverse flow of a phase current based on these results. A motor driving apparatus for driving a motor under a PWM control includes a rectification switching section for switching a rectification scheme from one to another based on the reverse current detection apparatus and a detection result thereof.

The subject of the present invention is to provide an optical transmitting device and an optical transmission system, capable of realizing an increase of multiple channels and an extension of a transmission distance at a low cost. In the present invention, the external modulation process is applied to a first optical signal (λ1), which is modulated by a transmission signal on a low frequency side for which low noise and distortion characteristics are required, out of the wideband frequency multiplexing electric signals by a first E/O converting unit (22). In contrast, the direct modulation process is applied to a second optical signal (λ2), which is modulated by a transmission signal on a high frequency side whose request for the transmission characteristic is not so high, by a second E/O converting unit (24) to execute an E/O conversion. As a result, an optical transmitting device and an optical transmission system, capable of realizing an increase of frequency range and multiple channels and an extension of a transmission distance can be manufactured at a low cost.

Embodiments of the invention provide a method and an apparatus for generating a total harmonic distortion reference signal. A triangle wave having a predetermined frequency and a predetermined amplitude is generated. The triangle wave is filtered to produce a signal substantially consisting of a sinusoid at the predetermined frequency and selected harmonics of predetermined amplitudes.

A magnetic recording media formed of magnetic alloy layer of Co as the main component on a substrate through an under-layer, a protective layer and a lubricant layer, stacked in this order, said under-layer comprises plural under-layers including a first under layer of a substantially amorphous and a second under layer of crystalline stacked in this order; and a Δ BH[0.01, 50] defined by |BH[0.01%]−BH[50%]|, as the difference between a height BH[0.01%] where a Bearing ratio is 0.01% and a height BH[50%] where a Bearing ratio is 50%, is not less than 3 nm and not more than 6 nm, where a Bearing Curve is given by a surface roughness curve of magnetic recording media.

According to the present invention, there is provided a magnetic recording medium 10 which includes: a non-magnetic base 1; a non-magnetic underlayer 3 formed on the non-magnetic base 1; a first recording layer 4 formed on the non-magnetic underlayer 3, the first recording layer 4 having a perpendicular magnetic anisotropy with an anisotropic magnetic field of H_k1, a thickness of t₁, and a saturation magnetization of Ms₁; and a second recording layer 5 formed above or under the first recording layer 4, the second recording layer 5 having a perpendicular magnetic anisotropy with an anisotropic magnetic field of H_k2, a thickness of t₂, and a saturation magnetization of Ms₂, wherein the anisotropic magnetic fields H_k1 and H_k2, the thicknesses t₁ and t₂, and the saturation magnetizations Ms₁ and Ms₂ satisfy H_k2<H_k1 and (t2·Ms₂)/(t₁ Ms₁)<1, respectively.

The invention provides a fast phase locking low-noise signal generator comprising a low-noise reference signal, a phase discriminator, a narrowband integrator, a broadband integrator, a proportional adder, a voltage controlled oscillator and a feedback network. An output signal of the voltage controlled oscillator passes through the feedback network, and is input to the phase discriminator together with the reference signal for phase discrimination. Of output signals of the phase discriminator, one channel is sent to the narrowband integrator, and the other channel is sent to the broadband integrator. The proportional adder proportionally adds voltages output by the narrowband integrator and broadband integrator to generate voltage controlled voltage of the voltage controlled oscillator. By adopting the two integrators of different bandwidths, two different loop bandwidths are formed, the large loop bandwidth improves the speed of phase locking, the loop is locked to the small bandwidth ultimately, and the characteristic of mutual restriction between small bandwidth and fast locking on a phase-locked loop is achieved.

An integrated circuit device of the present invention includes a plurality of signal processing circuits classified into a plurality of groups, each signal processing circuit including an amplifier circuit for amplifying an input electric signal and a bias circuit having an input terminal connected electrically to a bias source and supplying a bias input terminal of the amplifier circuit with an operation bias for an amplifying operation of the amplifier circuit; and a plurality of connection wirings arranged each for each of the groups separately, such that the input terminals of the bias circuits of the signal processing circuits in one of the groups are commonly connected through the connection wirings. This provides an integrated circuit device suppressing the lowering of an image quality in consideration of enabling lower power consumption, a low noise characteristic, and high integration, and an imaging apparatus using the integrated circuit.