86results about How to "Reduce current noise" patented technology

The invention discloses a vehicular visible light wireless digital voice communication system. The vehicular visible light wireless digital voice communication system comprises a sending module and a receiving module. The sending module comprises a digital audio acquisition unit, an RS coding unit, a PWM (pulse width modulation) unit, an LED (light emitting diode) drive unit and an LED transmitting unit, which are connected successively in circuit; the receiving module comprises a PIN photoelectric detection unit, a signal extraction unit, a PWM modulation unit, an RS decoding unit and a digital audio output unit, which are connected successively in circuit. The wireless digital voice communication system realizes instant voice communication between strange vehicles; an LED-based lamp is integrated with automobile lighting and communication without the need of an additional signal emission source installation space and occupation of scarce frequency spectrum resource. The voice signal transmission is high-speed and reliable, high in integration level, strong in anti-interference ability and low in cost, and bigger communication distance and more reliable communication are realized; moreover, a detector has high accuracy, high responsivity, low dark current, higher communication rate, stronger anti-interference ability and high reliability of a transmission channel.

The invention provides an adjustable electronic detonator control chip. A clock circuit of the chip is a RC oscillator; and a logic control circuit comprises a programmable delay module, an input/output interface, a serial communication interface, a prescaler, a central processor, and a counter. One end of the counter is connected with the power output end of a power management circuit; one end isearthed; one end is connected with the central processor through an internal bus; and the other end and the central processor, the programmable extension module and the prescaler are connected and are connected with the RC oscillator together. The invention also provides a chip controlling flow which comprises a plurality of implementing proposals including a synchronous learning course, a clockadjusting course, a state re-reading course, a writing delay time course, an ignition course and other sub-flows. The technical proposal realizes the electronic detonator control chip with good shockresistance and integratability and enough time delay precision, thereby realizing an electronic detonator with high time delay precision.

The invention discloses a timing control system and a method for a non-salient pole permanent magnet synchronous motor. The method comprises the following steps: the electrical angle position theta and the mechanical rotational speed omegam of a motor of a non-salient pole permanent magnet synchronous motor rotor are measured; the difference of a preset target rotational speed omegam<*> and omegam is obtained; the difference is performed with scale, integration and differential operation to obtain component instruction value uq<*> of q shaft voltage; voltage vectors ualpha<*> and ubeta<*> on a static coordinate system can be obtained by PARK inverse transformation of ud<*> and uq<*> by theta, wherein, ud<*> is zero; according to ualpha<*> and ubeta<*> of the voltage vector, a power device pulse-width signal can be generated by a space vector pulse width modulation (SVPWM) algorithm; according to the power device pulse-width signal, three-phase winding current is generated and is sent to the non-salient pole permanent magnet synchronous motor. The invention can realize speed loop no-current sensor vector control of the non-salient pole permanent magnet synchronous motor and lower hardware cost for timing.

An LED driver circuit includes a power controller, a voltage regulator, a detecting resistor, a light emitting device, and a voltage detecting circuit. The voltage detecting circuit has a first input end connected to a higher potential end of the detecting resistor, and a second input end thereof is connected to a lower potential end of the detecting resistor. The output end of the voltage detecting circuit is connected to a feedback end of the power controller so as to output a detected voltage signal to the power controller for adjusting the output voltage and supplying a stable and proper value of current to the light emitting device. The voltage detecting circuit is a differential amplifier capable of detecting the voltage difference between the detecting resistor and amplifying it as a feedback to the power controller. Therefore, the output current from the power controller is precisely controlled.

The invention discloses an intelligent power module. The module comprises an input pin, an output pin, an inverting circuit and a driving unit, wherein an input end of the inverting circuit is connected with the input pin; an output end of the inverting circuit is connected with the output pin; the inverting circuit comprises a plurality of power switch MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) and a plurality of follow current MOSFET which are correspondingly connected with the plurality of power switch MOSFET in parallel; the power switch MOSFET and the follow current MOSFET are MOSFET; the inverting circuit is used for inverting direct current input by the input pin into alternating current; the driving unit is connected with grid electrodes of the plurality of power switch MOSFET respectively; the driving unit is used for driving the plurality of power switch MOSFET to be switched on and off, so as to control the inverting circuit to be inverted, so that the switching-on speed of the power switch MOSFET can be improved, current noises are reduced, power loss is reduced and the applicability of a product is improved; the intelligent power module is especially applicable to an electric control system with ultralow power consumption requirements or an electric control system adopting a high-frequency pulse width modulation algorithm. The invention further discloses an air conditioner.

The invention provides an intelligent power module, a power electronic device and an air conditioner. The intelligent power module comprises a drive integrated unit, a power factor correction unit and an inverter switch unit, wherein the inverter switch unit comprises three upper bridge arm power devices and three lower bridge arm power devices; a first gallium nitride diode is connected between a source and a drain of each upper bridge arm power device; a second gallium nitride diode is connected between the source and the drain of each lower bridge arm power device; and grids of the three upper bridge arm power devices and the grids of the three lower bridge arm power devices are connected to corresponding gate drive interfaces in the drive integrated unit respectively. Through the technical scheme provided by the invention, current noise Irr generated in a drive circuit is reduced while the condition that the intelligent power module has low power consumption and short turn-on time is ensured, and the applicability of the intelligent power module is improved.

The invention relates to an impedance adjusting method, a radio frequency circuit, communication equipment and computer equipment. The impedance adjusting method is applied to the communication equipment. The method comprises the following steps: carrying out load traction on a power amplifier in the communication equipment to obtain a first mapping relation between an impedance value of an antenna matching circuit and an output current of the power amplifier and a second mapping relation between the impedance value and an output power of the power amplifier; determining an impedance value interval corresponding to the preset power interval according to the second mapping relation; determining a selectable impedance point according to the impedance value interval and a first mapping relation, wherein the impedance value of the optional impedance point is within the impedance value interval, and the output current corresponding to the impedance value is smaller than the current threshold value; the current threshold value is a corresponding current value when a noise value generated when the power amplifier works in the preset power interval is greater than or equal to the noise threshold value. The current noise generated by the power amplifier can be reduced on the premise of ensuring the communication quality.