203results about How to "Reduce switching noise" patented technology

The present invention discloses a PFC-PWM controller having interleaved switching. A PFC stage generates a PFC signal for switching a PFC boost converter of a power converter. A PWM stage generates a PWM signal for switching a DC-to-DC converter of the power converter. The PFC-PWM controller includes a power manager for generating a discharge current and a burst-signal. Under light-load conditions, the discharge current decreases in proportion to a load of the power converter. The burst signal is utilized to disable the PFC signal in a suspended condition for power saving. A pulse width of the pulse-signal ensures a dead time to spread switching signals, such as the PFC and PWM signals, and reduces switching noise. When the discharge current decreases, the pulse width of the pulse-signal will increase and a frequency of the pulse-signal will decrease correspondingly. This further reduces power consumption under light-load and zero-load conditions.

The present invention includes a turn-off signal modulating circuit that periodically varies a turn-off timing of a switching element 2 at a preset modulation time after a current detection by a drain current detecting circuit 15, and by modulating the peak of a current flowing through the switching element 2, diffuses switching noise while preventing concentration of an oscillating frequency at a constant frequency even under a constant input voltage and a constant load.

A switching power supply circuit ready for a wide range and including a power factor improving function is disclosed which can achieve reduction in cost, reduction in size and weight of the circuit and reduction of the power loss by reducing the number of converter sections with respect to the number of stages in a starting order of secondary side DC output voltages. A plurality of switching converters (101), (102) are of the composite resonance type wherein a partial resonance voltage circuit is combined with a switching converter of the current resonance type according to a half-bridge connection system. Changeover control is performed such that a rectification circuit serves as a voltage doubler rectification circuit at an AC voltage equal to or lower than 150 V, but serves as a full-wave rectification circuit at another AC voltage equal to or higher than 150 V. Power factor improvement is implemented by feeding back the voltages of outputs of the converters to a rectification current path by a power factor improving transformer (VFT) and interrupting the rectification current by means of a rectification diode to expand the

The present invention includes a turn-off signal modulating circuit that periodically varies a turn-off timing of a switching element 2 at a preset modulation time after a current detection by a drain current detecting circuit 15, and by modulating the peak of a current flowing through the switching element 2, diffuses switching noise while preventing concentration of an oscillating frequency at a constant frequency even under a constant input voltage and a constant load.

A control device receives a power supply current from a current sensor and a reactor current from a current sensor and detects a maximum value and a minimum value from the reactor current and from the detected maximum and minimum values and the power supply current determines whether the reactor current traverses the zero point, and if so the control device generates and outputs a signal to an up converter which responds to the signal by stopping switching to perform an up or down converting operation.

An electrical interface device (10) for towing, operable to facilitate releasably coupling one or more electrical subsystems of a towing vehicle (12) and a towed vehicle, and including associated modular, removable circuitry (24). The circuitry (24) may provide overload, short-circuit, and reverse connection protection and power signal filtering. Alternative or additional circuitry may be added to support other functionality, including interfacing a brake control subsystem. Circular receptacle and flat plug connectors (20,22) are provided to accommodate without modification a variety of electrical connectors. Covers (32,33) are also provided to protect unused connectors from adverse environmental conditions.

A backlight inverter for an LCD panel of an asynchronous pulse width modulation (PWM) driving type which is capable of driving a plurality of cold cathode fluorescent lamps (CCFLs) in pairs and controlling a plurality of PWM drive signals for respective operations of the lamps to make the phases thereof different. The backlight inverter comprises a main driving integrated circuit (IC), at least one sub-driving IC, and a plurality of lamp operating circuits for operating the pairs of lamps in response to the first and second PWM drive signals and the third and fourth PWM drive signals, respectively. The lamps have different PWM on / off periods so that overshoot of a power supply circuit can be reduced so as to keep the entire system power stable.

The invention discloses an infrared proximity transducer capable of inhibiting an environmental noise. In the prior art, there are problems of poor capability for inhibition of environmental noises and high fallout ratio on the condition of strong background light and high temperature; however, the above-mentioned problems are solved by utilizing the infrared proximity transducer. The infrared proximity transducer comprises a photodiode circuit, an infrared emitting diode, a current control circuit, an analog to digital conversion circuit, a digital to analog conversion circuit, a time sequence control circuit and a data storage circuit. The photodiode circuit converts a detected optical signal to a current signal; the current signal passes through the current control circuit and is output to the analog to digital conversion circuit; the digital to analog conversion circuit converts an output of the analog to digital conversion circuit into a current signal and then the current signalis feedbacked to an input terminal of the analog to digital conversion circuit; the output of the analog to digital conversion circuit is sent to an external microprocessor through the data storage circuit; and the time sequence control circuit provides a time sequence control signal for all circuits. According to the invention, an effect of filtering and removing environmental noises is good; and a degree of closeness of an object can be accurately detected in the environment of strong background light and high temperature; therefore, the infrared proximity transducer can be applied to intelligent control of electronic products.

A disk array system is provided, which can improve data reliability by verifying addressing correctness of data access by applying a redundant code to user data even if using an HDD compatible with serial ATA, etc. whose sector length cannot be extended. When writing the object data to an HDD, a controller stores partly-extracted data of the object data in a control area and performs an XOR operation between the partly-extracted data and a check code generated by calculations. Then, the operation-resultant data (CC-embedded data) are returned to the object data and written in the HDD. Also, when reading the object data from the HDD, the controller fetches the CC-embedded data, performs an. XOR operation between the fetched data and the check code, and compares and collates the operation-resultant data with the partly-extracted data in the control area to check the addressing correctness and restore the user data.

This invention provides a power supply device capable of widening a conduction period of an input current by a simple control to improve a power factor, and reducing a harmonic distortion of the input current The power supply device comprises a rectifier circuit, a reactor, a power factor correction circuit having switching elements, capacitors and a reverse-current blocking rectifier elements, a smoothing capacitor for smoothing an output voltage of the power factor correction circuit to obtain a DC voltage, a pulse signal controller generating and outputting a pulse signal for turning on and off the switching elements, and a driver for receiving the pulse signal to drive a switching elements of the power factor correction circuit.

A transition mode power converter having an active snubber the operation of which is controlled using an auxiliary winding on the transformer of the power converter. In one embodiment, the power converter includes a transformer having a primary winding connected to a voltage source, a primary switch, an auxiliary switch, a capacitor, and an auxiliary winding on the transformer. The primary switch includes a first terminal connected to the primary winding of the transformer and a second terminal connected to a common node. The auxiliary switch includes a first terminal connected to the voltage source and to the primary winding. The capacitor is connected between a second terminal of the auxiliary switch and the first terminal of the primary switch. The auxiliary winding of the transformer is connected to a third terminal of the auxiliary switch and controls operation of the auxiliary switch via the third terminal.

Embodiments of the invention provide a power semiconductor module wherein it is possible to reduce switching noise generated in a switching element, and at the same time, to reduce thermal resistance between a power semiconductor chip and an insulating substrate. In some embodiments, by a capacitor being installed between a printed substrate and an insulating substrate so as to be adjacent to a power semiconductor chip which is a switching element, it is possible to reduce switching noise generated in the switching element, and furthermore, it is possible to reduce thermal resistance between the power semiconductor chip and insulating substrate.

The improved single stage power converter circuit topology substantially reduces EMI that is conducted to the AC line, reduces input AC current inrush, improves output ripples by the use of an auxiliary supply near zero crossings of the line AC voltage, provides Power Factors greater than 0.95, provides Total Harmonic Distortions less than 15%, and maintains constant power, including constant power in a non-linear output load. Further, this circuit topology provides output open and short circuit protections by reducing current stress in power components. This topology can also make the power source to appear as a fast-acting variable impedance source, an ideal source for powering an output load that has negative resistance characteristics such as gas discharge lamps.

What is provided is a direct-current converter which improves unstableness of operations owing to an error of a bottom detection circuit and fluctuations of a detection point which are caused by disturbance. The direct-current converter includes a bottom detection circuit 13 which detects a minimum voltage of a main switch Q1 after an auxiliary switch Q2 is switched off, an ideal gate signal generation circuit 21 which generates an ideal gate signal for switching on the main switch Q1 at a time of the minimum voltage of the main switch Q1 based on an output of the bottom detection circuit 13, a comparison circuit 22 which calculates an error output between the ideal gate signal generated by the ideal gate signal generation circuit 21 and an actual gate signal which switches on the main switch Q1, and a first delay circuit 14 which controls a delay of an ON time of the main switch Q1 by the actual gate signal based on the error output of the comparison circuit 22, thereby performing control to make the actual gate signal approach the ideal gate signal.

The invention provides a convenient method for controlling direction of rotation of a synchronous motor of a single-phase permanent magnet. The method comprises the following steps: A. arranging a power switch of stator exciting current and ensuring the power switch to conform to the following requirements: when a rotor of the permanent magnet is motionless, the power switch is conducted after the power voltage is connected, or after the rotor of the permanent magnet rotates, the power switch is conducted if the direction of rotation conforms to the set requirement, or after the rotor of the permanent magnet rotates, the power switch is turned off if the direction of rotation is opposite to the set requirement, and when the rotor of the permanent magnet only shakes or wriggles, the power switch is conducted; B. arranging a permanent magnet rotor field polarity sensing device obtaining the real-time field polarity of the permanent magnet rotor in designated position; and C. using the simplest sequential logical circuit to complete each judgment in the step A, thus implementing control of the direction of rotation of the rotor of the permanent magnet. The invention has the advantages of simple and practical control method, simple control circuit, low cost, high reliability, strong interference resistance, capability of effectively reducing the noises of thyristor switches, etc.

The improved single stage power converter circuit topology substantially reduces EMI that is conducted to the AC line, reduces input AC current inrush, improves output ripples by the use of an auxiliary supply near zero crossings of the line AC voltage, provides Power Factors greater than 0.95, provides Total Harmonic Distortions less than 15%, and maintains constant power, including constant power in a non-linear output load. Further, this circuit topology provides output open and short circuit protections by reducing current stress in power components. This topology can also make the power source to appear as a fast-acting variable impedance source, an ideal source for powering an output load that has negative resistance characteristics such as gas discharge lamps.

A DC-DC converter for boosting an input voltage to a higher output voltage includes an inductor, a field effect transistor, a first ON signal generating circuit, a second ON signal generating circuit, an OFF signal generating circuit, a transistor driving signal generating circuit, and a switching frequency varying circuit. The switching frequency varying circuit changes a first ON time with the passage of time, so that the energy of switching noise is diffused without concentrating at specific frequencies. Thus, magnitude of the energy of switching noise in each switching frequency can be reduced.

A multi-chip BGA package has two or more rerouted chips, each of which has one or more electrode plates. The electrode plate is coplanar with rerouting lines on the rerouted chip and may act as a decoupling capacitor, reducing simultaneous switching noise from fluctuations in power voltage, without causing an increase in thickness of the package. Further, each pair of rerouting lines on upper and lower rerouted chips includes two or more interconnection bumps. This reduces inductance and resistance of electric signal propagation. Therefore, the multi-chip BGA package of this invention can realize small, thin, high-speed and high-density memory devices.

A method and system for controlling an electrohydraulic braking system for a motor vehicle having an antilock braking control function and an electrically controllable pressure generating device having a cylinder-piston arrangement having a hydraulic pressure chamber and a piston displaceable by an electromechanical actuator so that a predetermined pressure can be set in the chamber, and having a number of hydraulically wheel brakes connected to the hydraulic pressure chamber by an electrically actuatable inlet valve and to a pressure medium reservoir by means of an electrically actuatable outlet valve. The cylinder-piston arrangement is actuated in case of antilock controlling at all wheel brake for setting an individual wheel target pressure at each wheel brake, such that the pressure in the hydraulic pressure chamber is set to the greatest wheel target pressure.

A new method to reduce switching noise on an integrated circuit device is achieved. The method comprises providing an integrated circuit device comprising a power supply, a ground, and a plurality of switchable capacitors. Each switchable capacitor is connected from the power supply to ground. The operating mode of the integrated circuit device is tracked. An optimal capacitance value is selected based on the operating mode. A set of switchable capacitors from the plurality of switchable capacitors is selected to thereby connect the optimal capacitance value from the power supply to ground.

A TD converter is provided for digitally converting a delay time value into a digital value. In the TD converter, an oscillator circuit part inputs time domain data. A first-state counter circuit part measures a number of waves of an output oscillation waveform from the oscillator circuit part when time domain data is in a first state, and a second-state counter circuit part measures a number of waves of the output oscillation waveform from the oscillator circuit part when the time domain data is in a second state. An output signal generator part generates an output signal based on output count values of the first-state counter circuit part and the second-state counter circuit part, and a frequency control circuit controls the oscillator circuit part to always oscillate and to control an oscillation frequency of the oscillator circuit part.

The invention carries out field weakening control on a brushless motor without use of preset controlled variables, such as table values, and independently of the input voltage of an inverter circuit 3 in a motor driving device that drives the brushless motor. The motor driving device comprises an inverter circuit 3 that converts the output voltage of a voltage source 1 into a three-phase alternating current, and outputs it to a motor 2; a rotor position estimating unit 5 that estimates the rotor position of the brushless motor; and an inverter control unit 4a that controls the inverter circuit 3 so that the brushless motor is driven by a current based on the estimated rotor position. The inverter control unit 4a determines a value [beta] of advance angle, which is the advance angle of a current supplied to the brushless motor relative to the estimated rotor position, so that the difference between commanded number of revolutions fo and actual number of revolutions f is minimized.

The invention discloses an LCC serial-parallel resonant power supply and a method for increasing switching frequency by the power supply. The LCC serial-parallel resonant power supply comprises a full-bridge rectifier circuit, a filter capacitor assembly, a full-bridge inverter circuit, an LCC serial-parallel resonant circuit, a main power transformer T1, a high voltage rectifier assembly, a high voltage energy storage filter capacitor C11 and a resistor assembly. According to the power supply, by the aid of the soft-switching technology and the LCC serial-parallel resonant circuit, a power switching tube in the full-bridge inverter circuit is switched on and off under the condition of zero voltage, the switching frequency of the power switching tube is increased, switching loss is decreased, switching noise is reduced, and power efficiency is improved.

Disclosed are an integrated circuit component capable of simply mounting at low cost a chip part which adjusts impedance of wiring patterns as well as capable of effectively reducing switching noise from an integrated circuit, and a method for mounting the chip part. The integrated circuit component of the present invention has a constitution that a bypass capacitor is mounted on a wiring board side of a gap between the wiring board and an LSI chip. Therefore, as compared with a case where the capacitor is mounted on the LSI chip side, a transmission path through the capacitor can be extremely shortened. As a result, inductance components of the feeder line can be reduced, so that a response delay of power transmitted through the feeder line can be sufficiently suppressed.

A level shifter includes a latch having a first output node and a second output node complementary to each other. A first pre-charge transistor has a source-drain path coupled between a positive power supply node and the first output node. A second pre-charge transistor has a source-drain path coupled between the positive power supply node and the second output node. The integrated circuit structure further includes a delay-inverter coupled between a signal input node and inputs of a first NMOS transistor and a second NMOS transistor in the latch. The delay-inverter is configured to allow one of the first pre-charge transistor and the second pre-charge transistor to pre-charge a respective one of the first output node and the second output node before an input signal at the signal input node arrives at a gate of a respective one of the first NMOS transistor and the second NMOS transistor. The invention has advantages of high shifting speed, low shifting noise and reduced chip applying area.

Provided is a switching power supply device that can limit the generation of recovery current of diodes connected in parallel between the two ends of a synchronized rectifying element by the addition of a simple circuit, and that improves efficiency and facilitates miniaturization. The device comprises a synchronized rectifying element (SR1) that turns on and off complementarily with a main oscillation element (TR1) that is connected in series with an input power supply (E), and a parasitic diode (DSR1) that is connected to the two ends of the synchronized rectifying element (SR1) in a direction enabling current supply toward a smoothing circuit (16). The device is equipped with a control circuit (PW2) that generates a control pulse with which is set the time delay for turning on the oscillation element (TR1) after a certain period of time after the synchronized rectifying element (SR1) is turned off has elapsed, and that drives the main oscillation element (TR1) and the synchronized rectifying element (SR1) based on the control pulse. An auxiliary rectification circuit (22) comprising a series circuit formed by an auxiliary switch element (Q1) and an auxiliary capacitor (C1) driven by the control circuit (PW2) is provided between the two ends of the parasitic diode (DSR1).

A switching power supply circuit includes a plurality of switching converters, each including a partial resonance voltage circuit combined with a current resonance type switching converter using a half-bridge connection system. For changeover control, a rectification circuit serves as a voltage doubler rectification circuit at an AC voltage less than or equal to 150V, but serves as a full-wave rectification circuit at an AC voltage greater than or equal to 150V. The voltage output of the converters is fed back to a rectification current path by a power factor improving transformer, the rectification current being interrupted by means of a rectification diode to expand the conduction angle of the AC input current. A DC switch circuit in the rectification current path is switched between on and off conditions in response to the input of a predetermined starting signal to control the starting order of the secondary side DC output voltage.

Embodiments of the present invention provide a system that controls noise in a power system that includes a power rail and a ground rail. The system includes a MOS transistor coupled in series with a decoupling capacitor between the power rail and the ground rail and an inductive packaging connection coupled to the power rail in parallel with the MOS transistor and the decoupling capacitor. The combination of MOS transistor, decoupling capacitor, and inductive packaging connection form a resonant circuit. During operation, the system determines if there is noise in a Vdd signal on the power rail. Based on the noise present in the Vdd signal, the system adjusts the impedance of the MOS transistor to reduce the noise in a frequency range near a frequency of interest (ωinterest) of the resonant circuit without causing an unnecessary increase in switching noise at other frequencies.