140results about How to "Improve transient response speed" patented technology

The invention discloses a low dropout regulator, which comprises an error amplifier, a buffer circuit, a P-channel metal oxide semiconductor (PMOS) regulation transistor, an N-channel metal oxide semiconductor (NMOS) push-pull tube, a voltage division feedback circuit, a compensation circuit and an output circuit, wherein the gate of the PMOS regulation transistor is connected with the output end of the buffer circuit, the source of the PMOS regulation transistor is connected with power voltage, and the drain of the PMOS regulation transistor is used as the output end of the low dropout regulator; the gate of the NMOS push-pull tube is connected with the output end of the error amplifier, the drain of the NMOS push-pull tube is connected with the drain of the PMOS regulation transistor, and the source of the NMOS push-pull tube is grounded; and the error amplifier, the compensation circuit, the buffer circuit, the PMOS regulation transistor, the voltage division feedback circuit and an output circuit form a main control loop, and the error amplifier, the compensation circuit, the NMOS push-pull tube, the voltage division feedback circuit and the output circuit form an auxiliary control loop. According to the low dropout regulator, the transient response of the regulator can be quickened, and the accuracy of output voltage can be improved.

The invention relates to a constant voltage constant current control circuit and a constant voltage constant current control method thereof, and is applied to a flyback converter. The constant voltage constant current control circuit generates a constant voltage/constant current control signal according to an output voltage feedback signal and an output current feedback signal to control the duty ratio of a switching signal of a main switching tube in the flyback converter and further ensure that the output voltage or output current of the flyback converter is kept constant. A circuit coupling control scheme is adopted, and then constant voltage or constant current control can be realized only by one capacitor, so that the constant voltage constant current control circuit has a simple structure; and moreover, the output voltage feedback signal which precisely represents the output voltage information of a secondary side and the output current feedback signal which precisely represents the output current information of the secondary side can be obtained by a voltage feedback circuit and a current feedback circuit, so that the constant voltage constant current control circuit is high in accuracy.

The invention discloses a bifrequency control method of switch power supply and a device thereof. A controller combines two groups of pulses with different frequencies to realize control of a switch convertor according to output state of the switch convertor. The invention is applicable to controlling of switch convertors of various topological structures and has the advantages that the control loop is simple and reliable, free of network compensation, fast speed in transient response and low noise in electromagnetic interference (EMI).

The invention relates to a low dropout regulator. The low dropout regulator comprises a feedback circuit, a reference voltage unit which is connected with the cathode of an error amplifier. A control end of a first on-element in the feedback circuit is connected with an output end of the error amplifier. An input end of the first on-element and an output end of the first on-element are respectively connected with a power supply and an output end of the regulator. A resistor branch and a circumscribed capacitor branch are connected between the output end of the regulator and ground in parallel. The resistor branch is provided with a first resistor and a second resistor. The first resistor and the second resistor are in series. The anode of the error amplifier is connected with the first resistor and the second resistor. The first resistor and the second resistor feed back signals. An output end of a second on-element is connected with the ground through a third resistor. An input end of the second on-element is connected with the output end of the regulator, and a control end of the second on-element is connected with the output end of the error amplifier. The problems that transmission voltage fluctuation is too large and stable time is too long caused by load current saltus step of the low dropout regulator are solved, static power consumption increase is reduced to a maximized degree, the circuit structure is simple, transient response speed and precision of low dropout regulator (LDO) circuits are greatly improved.

The invention belongs to the field of voltage stabilizers, the invention relates to a voltage stabilizer and particularly relates to a digital low-dropout voltage stabilizer. The stabilizer comprisesa voltage input end, a voltage output end, a first reference voltage input end, a second reference voltage input end, a third reference voltage input end, a voltage comparator, a transient detector, acoarse adjustment controller, a fine adjustment controller, a first transistor array, a second transistor array and a load capacitor. The stabilizer is advantaged in that a method of combining coarseadjustment and fine adjustment is adopted so that the transient response speed and precision are improved.

The invention discloses a transient voltage suppressor. The transient voltage suppressor is provided with a signal end and a grounding end. The transient voltage suppressor comprises a capacitive diode assembly and a first Zener diode, which are connected in series. The capacitive diode assembly comprises a first diode and a second diode, wherein the first and second diodes are formed in the same semiconductor chip and are in reverse parallel connection in the semiconductor chip. The transient voltage suppressor employs the capacitive diode assembly as a nonpolar capacitor element, thereby improving the transient response speed of the transient voltage suppressor.

The invention discloses a control method for a three-phase PWM rectifier suitable for power grid waveform distortion. The control method for the three-phase PWM rectifier suitable for the power grid waveform distortion mainly includes that extracting a current reference signal under input voltage distortion and unbalanced disturbance, and actively injecting negative-sequence current, improved dead-beat inner current loop which is forecast through combining with linear extrapolation, and outer direct voltage loop performed with active disturbance rejection control. The control method for the three-phase PWM rectifier suitable for the power grid waveform distortion plays roles of inhibiting the harmonic wave of the input current of the PWM rectifier, injecting proper negative-sequence current to eliminate the secondary power pulse of the output direct current voltage of the PWM rectifier, improving the transient response of the output direct current voltage, and compensating the influences of all kinds of delay on the dead-beat control. The control method for the three-phase PWM rectifier suitable for the power grid waveform distortion is capable of obviously reducing the secondary wave of the output direct current voltage under the disturbance of the input harmonic wave and unbalanced voltage, improving the transient response speed of the PWM rectifier, reducing the transient offset of the direct current voltage, and improving the system control precision.

The invention relates to a double-closed-loop feedback-control module, wherein two closed-loop control loops are formed in the starting process and the holding stage of a contactor to directly and accurately control the coil current of the contactor, so that the optimizing control for the integral action characteristic of the contactor can be carried out, and the integral performance index of the contactor is comprehensively improved. The double-closed-loop feedback-control module has low hardware cost, the voltage-adjusting rate of a system can be improved, the transient response speed of the system is increased, and the stability of the system is enhanced.

The invention discloses a double-pulse cross-cycle modulation method for a switching power supply and a device thereof. After an output voltage vo of a main circuit is detected by a voltage detection device, and then the value of the output voltage vo is compared with the value of a reference voltage Vref and a value obtained by subtracting an error value (Vr-eref) from the reference voltage; if the vo is more than the Vref, a comparator outputs a low-level signal; if the vo is more than the Vr-eref and is less than the Vref, the comparator outputs a corresponding low duty cycle pulse signal; if the vo is less than the Vr-eref, the comparator outputs a corresponding high duty cycle pulse signal; within a clock cycle, a pulse selector selects a high duty cycle pulse signal and a low duty cycle pulse signal from a pulse generator according to the output of the comparator, or the pulse signal is not output; two pulse signals with different duty cycles are adopted to serve as the driving of a switch device; the voltage ripple output by a system is relatively small, the dynamic range of the input voltage of a load is widened, the system stability is enhanced, and the transient response speed is increased.

The invention discloses a multiway LED constant current controller and a control method. The multiway LED constant current controller is used for providing switch control signals to a power switch tube in a power-level circuit outside to control open-closed states of the power switch tube so as to enable the power-level circuit to generate constant current used for driving multiway LED lamp strings. The multiway LED constant current controller comprises a control loop which comprises a loop compensation network formed by multiple compensation signal maintaining elements. The multiway LED constant current controller connects the corresponding compensation signal maintaining elements in the control loop according to loaded states to enable the compensation signal maintaining elements to be respectively used for maintaining stable-state compensation signals of the control loop under different loaded states, and sets stable-state compensation signals when the loaded states change. By the multiway LED constant current controller and the control method, transient response speed when the loaded states change can be increased.

The invention provides a control method of a three-phase dual-active-bridge DC converter under a current optimal modulation. The method comprises a step of collecting DC side output voltage V2, DC side output current I2 and DC side input voltage V1 in each switch cycle, a step of multiplying the collected V2 by I2 to obtain a transmission power Po, at the same time multiplying V2 by a transformer transformation ratio N, dividing the above product by V1, and obtain a voltage transformation ratio d, a step of allowing Po and d to go through an optimal modulation strategy link to obtain the reference value D1* and D2* of duty ratios D1 and D2, and then obtaining the duty ratios D1 and D2 through two large inertia links or pure integrator links, a step of allowing the duty ratios D1 and D2 to go through an optimal amplitude limit value calculation link, and obtaining the optimal amplitude limit value Df_lim of a phase shift ratio, a step of carrying out difference comparison on a DC side output reference value V2ref and V2, allowing a difference to go through a PI regulator and an amplitude limit link with an amplitude limit value, and obtaining a phase shift ratio Df, and a step of obtaining the driving signal of each switch device according to the duty ratios D1 and D2 and the phase shift ratio Df, and driving a corresponding switch device.

The invention discloses a capacitive diode assembly and a manufacturing method of the capacitive diode assembly. The capacitive diode assembly comprises a first conductive type of semiconductor substrate, a second conductive type of epitaxial layer which is arranged on the semiconductor substrate, a first conductive type of isolation area, a first conductive type of first doped area, a second conductive type of second doped area and an interconnection structure, wherein the second conductive type is different from the first conductive type; the first conductive type of isolation area; the first conductive type of isolation area penetrates through the epitaxial layer from the surface of the epitaxial layer and extends to the semiconductor substrate so as to restrict a first active area of a first diode and a second active area of a second diode in the epitaxial layer and separate the first active area and the second active area mutually; the first conductive type of first doped area extends to the epitaxial layer from the surface of the epitaxial layer in the first active area; the second conductive type of second doped area extends to the epitaxial layer from the surface of the epitaxial layer in the second active area; and the interconnection structure electrically interconnects a part of the isolation area in the first active area with a part of the epitaxial layer in the first active area. The capacitive diode assembly can be used as a non-polar capacity cell and can improve the transient response speed of a transient voltage inhibitor.

The invention discloses an error amplifier, a transconductance amplifier and a gain amplifier for composing a DC-DC converter. The error amplifier, the transconductance amplifier and the gain amplifier are characterized in that: the transconductance amplifier amplifies an absolute value of difference between a reference voltage and a feedback voltage, outputs a current proportional to the absolute value of difference between the reference voltage and the feedback voltage, and provides a dynamic bias current for the gain amplifier; the gain amplifier amplifies the absolute value of difference between the reference voltage and the feedback voltage, and outputs or absorbs a current proportional to the absolute value of difference between the reference voltage and the feedback voltage; and when the feedback voltage is less than the reference voltage, an output end of the gain amplifier outputs a current, and when the feedback voltage is greater than the reference voltage, the output end of the gain amplifier absorbs a current. The error amplifier, the transconductance amplifier and the gain amplifier effectively increase efficiency, load adjustment rate, linear adjustment rate and transient state response speed of the DC-DC converter, and have good application prospect.

The invention provides a BOOST circuit for improving transient response and an application method of the BOOST circuit, the BOOST circuit comprises a BOOST converter for generating an output voltage higher than an input voltage, a current sampling module for generating a current detection signal, a switching device for controlling the on-off of a PWM modulation signal, and a control unit for generating a PWM modulation signal under the action of a reference voltage, a voltage feedback signal of an output voltage, a current detection signal and a slope compensation voltage and generating a modulation signal with a preset duty ratio in a set time period, and an output voltage slope sampling module for sampling the descending slope of the output voltage in the turn-off time of a switching device. According to the invention, the time for changing the inductive current to the final load current can be reduced, so that the transient response speed of BOOST is improved, and the stability of the system is ensured.

The invention discloses a low dropout linear voltage regulator capable of increasing transient state response speed. The low dropout linear voltage regulator comprises a transconductance amplifier, atrans-resistance amplifier, a current sampling circuit, a feedback resistance, a switch and a frequency compensation network. The low dropout linear voltage regulator disclosed by the invention adoptstwo working modes, namely double loop feedback control and single loop voltage feedback, when requirement on the transient state response speed is relatively high, the low dropout linear voltage regulator selects the current sampling circuit, the transconductance amplifier and the trans-resistance amplifier to be accessed into a feedback loop by virtue of switch control and selects the frequencycompensation network in the double loop feedback control mode for carrying out loop compensation, so that the transient state response speed of the low dropout linear voltage regulator is improved; and when the requirement on power consumption is relatively strict, the low dropout linear voltage regulator shuts off the current sampling circuit, shuts off the trans-resistance amplifier and is directly accessed into a loop by virtue of the transconductance amplifier, so as to form the single loop voltage feedback mode; and a single loop frequency compensation network is selected for carrying outthe frequency compensation, so that the power consumption of the low dropout linear voltage regulator is further reduced.

A time signal generator and a time generating method used in a power converter are provided. The time generating method includes following steps. An error delay signal is generated according to an error signal, wherein the error signal is related to an output voltage of the power converter. A time signal is generated according to the error signal and the error delay signal. The time signal may serve to improve a response speed of the power converter.

The invention discloses a back porch sampling circuit and a method for sampling back porch falling edging voltage. The back porch sampling circuit comprises a counting circuit, a detection circuit and a computing circuit, wherein the counting circuit is used for counting zero passage times and bottom number of a ring wave on a high frequency transformer auxiliary winding; the detection circuit is used for detecting time tvcn from turn-off of a switch element to nth zero passage of the ring wave or time tvan from the turn-off of the switch element to nth bottom of the ring wave; the computing circuit is used for figuring out time Tdis from the turn-off of the switch element to beginning of back porch falling edge of the ring wave; and n is nonnegative integer. According to the back porch sampling circuit and the method for sampling back porch falling edging voltage, the back porch sampling circuit can rapidly obtain control signals with high-precision stable voltage and constant current, is not influenced by temperature and can rapidly follow change of load and electric supply voltage, so that precision for stable voltage and constant current can be improved, and the transient response speed can be increased.

A method for amplifying a burst optical signal, a burst optical amplifier and system, and a communications system are provided according to embodiments of the present invention. The method includes: combining an auxiliary light and a signal light into a mixed light and outputting the mixed light, where the auxiliary light is a non-burst light, the signal light is a burst light, and power of the auxiliary light is set to be independent from power of the signal light; generating a pump light; and combining the pump light with the mixed light and inputting the combined light into a gain medium, so as to obtain an amplified mixed light. Present invention has the following advantages: reducing the delay time of enabling the burst optical amplifier, improving the transient response speed of the burst optical amplifier, and preventing the generation of a surge phenomenon, so as to prevent the generation of signal distortion.