32results about How to "Low audio noise" patented technology

An audio controlling device generates an audio mute signal based on the level of a power-supply voltage supplied from the source equipment, whether a clock signal has been input or not, whether a digital signal has been input or not, whether a multiplier circuit is being locked or not, an error rate, whether an audio clock detection circuit is being locked or not, the presence or absence of a change in a control signal, and whether a synchronization detection circuit is stable or not. The audio controlling device applies the audio mute signal to an audio mute circuit, while applying an OSD control signal to an OSD processing circuit. The audio mute circuit is placed in a mute state or unmute state based on the audio mute signal. The OSD processing circuit provides the on-screen display of a message based on the OSD control signal.

Disclosed herein is a display apparatus including: an available pixel section having a plurality of available pixel circuits; a plurality of scan lines; a plurality of capacitor lines; a plurality of signal lines; a driving circuit; and a monitor circuit wherein each of the available pixel circuits laid out on the available pixel section includes a display element having first and second pixel electrodes and a storage capacitor having first and second electrodes, in each of the available pixel circuits, the first pixel electrode and the first electrode are connected to one terminal of a switching device, in each of the available pixel circuits provided on any individual one of the rows, the second electrode is connected to the capacitor line provided for the individual row, and the common voltage signal with the level changing at time intervals determined in advance is supplied to the second pixel electrode of each of the display elements.

This invention relates to a boost high frequency AC / AC converter, which circuit is cascaded by an energy storage inductor, an input cycle converter, a HF transformer, an output cycle converter and an input and output filter circuit to turn a bad unstable AC current to a stable shared high grade sine AC current having the advantages of high frequency electric isolation, simple topological circuit, two stages of power transformation, two-way power-flow, high power factor at the supply side.

A distributed control type stream-light discharge process for desulfurizing fume is disclosed. Its wet discharge reactor is composed of thermal chemical reaction region and discharge plasma chemical reaction region with discharging electrode and receiving electrode. Said discharging electrode is connected with high-voltage power supply to generate stream-light discharge. Said power supply is controlled in distributed mode. After boiler fume goes through thermal chemical reaction and discharge plasma chemical reaction, the gas pollutant is removed and the liquid by-product is generated and dried to obtain dry powder. Its advantages are high power and long service life of power supply, low noise, and low cost.

The invention provides a same-frequency time division duplex digital interphone and a communication method thereof, and the method comprises the steps: an MCU controller controlling a radio frequencybaseband module to receive a voice signal in a first time slot and / or a second time slot, and the first time slot or the second time slot transmitting the voice signal; and the digital signal processor encoding and decoding the voice signal and judging whether the embedded signaling in the voice signal contains the duplex signal or not; when duplex signaling exists on the two time slots, the interphone outputting voices of the two time slots and forbidding emission; when duplex signaling exists on only one time slot, transmitting voice on the other time slot during transmission, performing theduplex signaling, and receiving the voice in one time slot with the duplex signaling; and when the duplex signaling is not received, transmitting the voice with the duplex signaling on one time slotduring transmission, and keeping the other time slot in a receiving state. According to the method, the TDMA technology of double time slots is adopted, and the two time slots can be respectively usedas a sending time slot and a receiving time slot, so that the same-frequency voice duplex communication is realized.

The invention relates to a differential buck direct current chopper type high frequency link inverter which is provided with a circuit consisting of two same high frequency electric insulation bidirectional buck direct current choppers which output low frequency positive half cycle unipolar sine pulse width modulating voltage wave and low frequency negative half cycle unipolar sine pulse width modulating voltage wave respectively in the form of differential circuits. LC filters are connected between an output end of a differential chopper and an output load and between an input direct current power supply and an input end of the differential chopper. The high frequency link inverter can transform an unstable direct current voltage into a required stable good-quality sine alternating current voltage, the high frequency link inverter has the advantages of high frequency electric isolation, strong matching ability of input voltage and output voltage, simple circuit topology, single stage power transformation, bidirectional power flow, high power density, high transformation efficiency, less output voltage ripple, strong load adaptability, low audio frequency noise, low cost, wide application prospects and the like and provides the key technology for a novel inverter power supply and a static convertor.

A system and method for using a circuit for providing power from multiple sources for a variable audio amplifier. The system includes a battery, a power supply and a controller which provides a power supply for the variable load demands of the amplifier, while still maintaining a substantially constant battery charge over an extended period of time.

Disclosed herein is a display apparatus including: an available pixel section having a plurality of available pixel circuits; a plurality of scan lines; a plurality of capacitor lines; a plurality of signal lines; a driving circuit; and a monitor circuit wherein each of the available pixel circuits laid out on the available pixel section includes a display element having first and second pixel electrodes and a storage capacitor having first and second electrodes, in each of the available pixel circuits, the first pixel electrode and the first electrode are connected to one terminal of a switching device, in each of the available pixel circuits provided on any individual one of the rows, the second electrode is connected to the capacitor line provided for the individual row, and the common voltage signal with the level changing at time intervals determined in advance is supplied to the second pixel electrode of each of the display elements.

A system and method for using a circuit for providing power from one or more battery packs charged by a AC-mains-provided electrical connection and which supply power to a hi-power, non-portable audio amplifier. The system includes a power supply sized to satisfy long time-basis average demands, a battery pack and with a controller which buffers or back-ends a power supply which is not otherwise capable of satisfying the variable load peak demands that an audio source imposes on the amplifier, while still maintaining a substantially constant battery charge over an extended period of time.

The present invention provides a step-up high-frequency link inverter, the circuit structure is composed of an input filter circuit, a dumping inductor, a high-frequency inverter, a high frequency transformer, a frequency current converter, an output filter circuit cascaded in orders, a high frequency electrical isolation fly-back converter energy feedback circuit composed of the frequency current converter, the high frequency energy storage transformer, the rectifier cascaded in orders is connected between the output load and the input DC power, capable of transforming the unstable DC voltage to the needed stable sinusoidal voltage having high grade, the inverter has advantages of high frequency electrical isolation, high output and input voltage matching ability, double-directional power flow, high transforming efficiency, small volume, light weight, small input current ripple, high load adaptability, lower audio noise, high credibility when the load is shortened, lower cost, large output capacity, wide application, establishing a critical technique for the new type inverter and static inverter having large capacity.

A digital video recording apparatus reduces the audio output level before and during changes in an audio encoding condition (stereo, monaural, etc.). One embodiment of the digital video recording apparatus multiplexes video and audio signals to produce an output stream. A video recording control means controls the apparatus according to user input and design.

Disclosed herein is a display apparatus including: an available pixel section; a plurality of scan lines; a plurality of capacitor lines; a plurality of signal lines; a driving circuit; a monitor circuit having a first monitor pixel section and a second monitor pixel section; at least two of following three correction systems of a capacitor-signal correction system, a video-signal correction system and the second monitor pixel section, and a common-voltage correction system; and a switch for selectively supplying pixel electric potentials detected by the first monitor pixel section and the second monitor pixel section to a desired one of the two or three correction systems.

The invention relates to a digital interphone with an adaptive vocoder. A main circuit comprises a control unit, a digital base band processing chip, a codec chip, a vocoder chip module and a radiofrequency front-end circuit, the control unit is respectively connected with the radiofrequency front-end circuit and the digital base band processing chip, the codec chip is respectively connected with the radiofrequency front-end circuit and the digital base band processing chip, and the vocoder chip module is connected with the digital base band processing chip, and consists of an AMBE (advanced multi-band excitation) vocoder chip and an SELP (sinusoidal excitation linear prediction) vocoder of the Tsinghua University which are integrated. The digital interphone with the vocoder chip module can sufficiently play the advantages of the various vocoders to the codec, better speech and voice quality can be realized in a signal environment with a wider range, audio noise received by the digital interphone is little, voice is clearer, and various European and Asian market needs can be met by the aid of high flexibility of a combination mode of the digital interphone.

A method for reducing audio noise of a display is provided. A horizontal synchronization signal, a reference signal and a substrate voltage signal are generated. The reference signal has a preset width at high level status. The status transition of the substrate voltage signal is based on each scan line corresponding to the horizontal synchronization signal. In each period of the substrate voltage signal, the status transition of the raising and falling edges is based on the high level status of the reference signal, and the transition timings of the raising edges and the falling edges are advanced or delayed based on a reference value of the high level status of the reference signal.

A method for reducing audio noise of a display comprises the following steps: generating a horizontal synchronizing signal, generating a reference signal and generating a substrate voltage signal. The high level state of the reference signal has a predetermined width; the substrate voltage signal switches the state according to each scanning line corresponding to the horizontal synchronizing signal; during each period of the substrate voltage signal, a rising edge and a falling edge of the substrate voltage signal switches the state based on the high level state of the reference signal, and the state switching time of the rising edge and the falling edge is antedated or delayed based on the reference value of the high level state.

The invention relates to a power supply circuit and a control method thereof. The power supply circuit receives input voltages to drive a plurality of loads, and comprises a plurality of switch circuits, a plurality of power conversion circuits and a phase deviation circuit; the plurality of switch circuits are respectively connected with the plurality of loads, the plurality of power conversion circuits are respectively connected with the plurality of switch circuits and the plurality of loads for converting the input voltages so as to provide a plurality of driving voltages to the plurality of loads when the corresponding switch circuits are conducted, and the phase deviation circuit is connected with the plurality of switch circuits and a system circuit for generating a plurality of delay signals to the control ends of the plurality of switch circuits according to the switch signals of the system circuit so as to ensure that the plurality of switch circuits are conducted or cut off, wherein the plurality of delay signals are converted to an enable state from a disable state at different time so as to ensure that the plurality of switch circuits are conducted at different time. According to the invention, the input currents do not rise or fall sharply when the plurality of switch circuits carry out action, therefore, the generation of audio noise is reduced, the stability is better, and the electronic elements are not easy to be damaged.

A method for reducing audio noise of a display is provided. A horizontal synchronization signal, a reference signal and a substrate voltage signal are generated. The reference signal has a preset width at high level status. The status transition of the substrate voltage signal is based on each scan line corresponding to the horizontal synchronization signal. In each period of the substrate voltage signal, the status transition of the raising and falling edges is based on the high level status of the reference signal, and the transition timings of the raising edges and the falling edges are advanced or delayed based on a reference value of the high level status of the reference signal.

The invention relates to a differential buck direct current chopper type high frequency link inverter which is provided with a circuit consisting of two same high frequency electric insulation bidirectional buck direct current choppers which output low frequency positive half cycle unipolar sine pulse width modulating voltage wave and low frequency negative half cycle unipolar sine pulse width modulating voltage wave respectively in the form of differential circuits. LC filters are connected between an output end of a differential chopper and an output load and between an input direct current power supply and an input end of the differential chopper. The high frequency link inverter can transform an unstable direct current voltage into a required stable good-quality sine alternating current voltage, the high frequency link inverter has the advantages of high frequency electric isolation, strong matching ability of input voltage and output voltage, simple circuit topology, single stage power transformation, bidirectional power flow, high power density, high transformation efficiency, less output voltage ripple, strong load adaptability, low audio frequency noise, low cost, wide application prospects and the like and provides the key technology for a novel inverter power supply and a static convertor.

A control method for reducing audio noise is disclosed. The method includes the steps of: providing an input power source; providing a power source converter having a component with a mechanical resonant frequency, coupled to the input terminal or the output terminal of the power source converter; providing an output capacitor and a load connected in parallel therebetween; making the power source converter operate in a burst mode; and controlling the electrical energy transferred from the input terminal to the output terminal of the power source converter during an operating period of every burst cycle, so as to reduce the audio noise of the power source converter.

The invention provides a mainboard, a noise reduction method and a terminal. The mainboard comprises a support piece and a filter capacitor, wherein the filter capacitor is mounted on the supporting piece; the surface of the filter capacitor is covered with a cured liquid resistance-capacitance layer, and the liquid resistance-capacitance layer comprises a liquid resistance-capacitance material; and the liquid resistance-capacitance layer is used for reducing noise generated by the filtering capacitor at the sound production position of the supporting piece.

The invention relates to a differential buck-boost direct current chopper type high frequency link inverter which is provided with a circuit consisting of two same high frequency electric insulation bidirectional buck direct current choppers which output low frequency positive half cycle unipolar sine pulse width modulating voltage wave and low frequency negative half cycle unipolar sine pulse width modulating voltage wave respectively in the form of differential circuits. Capacitance filters and LC filters are connected between an output end of a differential chopper and an output load and between an input direct current power supply and an input end of the differential chopper. The high frequency link inverter can transform an unstable direct current voltage into a required stable good-quality sine alternating current voltage, the high frequency link inverter has the advantages of high frequency electric isolation, strong matching ability of input voltage and output voltage, simple circuit topology, single stage power transformation, bidirectional power flow, high power density, high transformation efficiency, strong load adaptability, low audio frequency noise, the high reliability during load short circuit, low cost, wide application prospects and the like and provides the key technology for a novel small capacity inverter power supply and a static convertor.

A distributed control type stream-light discharge process for desulfurizing fume is disclosed. Its wet discharge reactor is composed of thermal chemical reaction region and discharge plasma chemical reaction region with discharging electrode and receiving electrode. Said discharging electrode is connected with high-voltage power supply to generate stream-light discharge. Said power supply is controlled in distributed mode. After boiler fume goes through thermal chemical reaction and discharge plasma chemical reaction, the gas pollutant is removed and the liquid by-product is generated and dried to obtain dry powder. Its advantages are high power and long service life of power supply, low noise, and low cost.

This invention relates to a boost high frequency AC / AC converter, which circuit is cascaded by an energy storage inductor, an input cycle converter, a HF transformer, an output cycle converter and an input and output filter circuit to turn a bad unstable AC current to a stable shared high grade sine AC current having the advantages of high frequency electric isolation, simple topological circuit, two stages of power transformation, two-way power-flow, high power factor at the supply side.

The invention discloses a micro-stepping low-noise stepping motor driving controller which comprises a delayer and a rotation counter, wherein the rotation counter is connected to a stepping motor via a micro-stepping subdivision sin / cos generator module, a pulse width modulation (PWM) generator module and an H-bridge driver, an input end of a stepping motor setting control register is connected with an external device through a serial peripheral interface (SPI) serial bus, an output end of the stepping motor setting control register is used for outputting data information or a control signal to the delayer, the rotation counter, the micro-stepping subdivision sin / cos generator module, the PWM generator module and the H-bridge driver, the micro-stepping subdivision sin / cos generator module comprises a subdivision logic controller, a Sin accumulator, a Cos accumulator and a subdivision frequency divider, and the PWM generator module comprises a delay counter, a Sin-PWM modulator, a Cos-PWM modulator and a PWM frequency divider. The micro-stepping low-noise stepping motor driving controller has a constant-voltage working structure with 256 subdivision stepping and adjustable amplitude, phase and frequency, and thus, the advantages of low vibration, low video frequency noise, low heat and high conversion efficiency during the working of the motor are achieved.

A noise processing device and its method are provided for a video / audio system having a high definition multimedia interface (HDMI). The noise processing device includes a detecting unit, a signal generating unit, and a decision unit. The noise processing method includes using the detecting unit to monitor a variation related to an audio signal and generate a detecting signal accordingly; using the signal generating unit to produce an adjustment signal according to the detecting signal; and using the decision unit to produce an output audio signal according to the audio signal and the adjustment signal. Another embodiment of the noise processing device includes a compensation tracking unit having a control unit. The compensation tracking unit produces an output audio signal according to a difference between the output audio signal itself and the audio signal and a gain of the control unit.

A method for reducing audio noise of a display comprises the following steps: generating a horizontal synchronizing signal, generating a reference signal and generating a substrate voltage signal. The high level state of the reference signal has a predetermined width; the substrate voltage signal switches the state according to each scanning line corresponding to the horizontal synchronizing signal; during each period of the substrate voltage signal, a rising edge and a falling edge of the substrate voltage signal switches the state based on the high level state of the reference signal, and the state switching time of the rising edge and the falling edge is antedated or delayed based on the reference value of the high level state.

This invention relates to a mono-pole two-way step-down DC converter high frequency link inverter, the circuit of which is composed of two same high frequency electric isolated two-way power flow step-down DC converters outputting inverse low frequency sine pulse DC voltages in differential circuit, which can convert a DC voltage to necessary sine AC voltage having the advantages of simple circuit topology, isolated AC load and DC supply high frequency, two-way power flow, mono-pole power transformation and small volume.