Abstract: The present application discloses a switch converter, and the switch converter comprises a first switch transistor, a second switch transistor, and an inductor, and further comprises: an acquisition unit for acquiring voltage of at least one end of the inductor, to obtain a first sampling signal and a second sampling signal; an operation unit, to obtain a current sampling signal based on the first sampling signal and the second sampling signal. The current sampling method in the switch converter of the present disclosure is simple, not easily affected by noise interference, and it has low requirements for devices, and adapts to different converters.

Abstract: A dynamic automotive turn signal circuit includes at least one drive control module configured to receive a power supply signal from a body control module (BCM) to start operation, where the drive control module outputs first control signals at different delays through a delay unit; and a light emitting diode (LED) light set connected to the drive control module and lit based on the first control signals. A dynamic automotive turn signal system is further provided. The dynamic automotive turn signal circuit and the dynamic automotive turn signal system uses an external resistor to preset a high-precision delay circuit to realize the function of dynamic flowing turn signals. The external resistor can be used to configure a turn-on delay and a turn-off delay of the internal driver chip, such that the channel turn-on time and turn-off time can be flexibly adjusted.

Abstract: Disclosed is a flyback converter, a switch control circuit and a control method thereof. A driving current regulation circuit generates a current regulation trigger signal at active state correspondingly according to an operating state of the flyback converter. A switch control driving unit regulates a driving current of the first switch transistor according to the current regulation trigger signal at active state, thus a variation rate of a drain-source voltage across the first switch transistor is slowed down to a preset range. According to the present disclosure, when it is detected that the flyback converter is operating in discontinuous conduction mode or the drain-source voltage across the first switch transistor is high, a switching rate of the first switch transistor is controlled to avoid the voltage across a rectifier switch transistor on a secondary side of the flyback converter to undergo a large jump, and the system EMI is good.

Abstract: The present application discloses a switching frequency synchronization circuit, a method therefor and a switching power supply. By comparing peak values of a second charging voltage signal which represents an internal clock signal and a first charging voltage signal which represents an external clock signal, it is determined whether the frequency of the external clock signal meets the requirement for frequency synchronization. In a case that the frequency meets the requirement, the second charging voltage signal is reset by the external clock signal to synchronize the frequency of the internal clock signal with the frequency of the external clock signal. The present disclosure does not need a complex phase-locked loop circuit, and adjust an internal clock frequency by simple voltage comparison and synchronization mode. The control circuit is simplified and the overall system cost is reduced.

Abstract: A light source driving circuit and a communication device for a display system are provided. The communication device includes a control unit and at least one string light source driving circuit. The control unit includes an output interface for transmitting the control commands or data and a reading back data input interface. Each string light source driving circuit includes a plurality of light source driving circuits. The control unit transmits the control commands or data to the first light source driving circuit of each string light source driving circuit through the output interface. The first driving circuit takes out the commands or data required at the current stage after receiving the control command or data, and then repackages the commands or data of the remaining driving circuits, and transmits the repackaged data packet through the serial output interface and the parallel interfaces or the parallel interfaces.

Abstract: The present application discloses an electronic fuse circuit and a circuit system using the same. During startup operation, the circuit system using the electronic fuse circuit of the present application detects an amplitude of the load voltage by a second protection circuit, when the voltage exceeds a set second threshold signal, the electronic fuse circuit is controlled to be turned off; during normal operation, a current of a path where the electronic switch is located is monitored by a first protection circuit to prevent a current of the circuit system from overcurrent. According to the technical solution of the present disclosure, the load can be prevented from damage caused by a failure such as short circuit and electricity leakage of the switch power supply, and the system can be protected from overcurrent.

Abstract: A light source driving circuit and a communication device for display system are provided. The communication device includes a control unit and at least one string light source driving circuit. The control unit includes an output interface for transmitting control commands or data and a data reading back input interface. Each string light source driving circuit includes a plurality of light source driving circuits, and each light source driving circuit interface includes a serial input interface, a serial output interface, parallel interfaces, and at least one current output interface. The serial input interface and serial output interface of the plurality of light source driving circuits are cascaded with each other as a first channel of the control commands or data transmission. The parallel interfaces of each driving circuit in the plurality of driving circuits are coupled with each other as a second channel of the control commands and data transmission.

Abstract: Disclosed is a power conversion circuit for quick response and a switching power supply, wherein an error compensation signal is obtained according to a sampled signal representing an output feedback signal or an average current through the inductor. A PWM control signal is generated according to the error compensation signal, a ramp signal, and a proportional signal, and is used to control switching operations of a main power switch transistor, the proportional signal is proportional to an input voltage or/and an output voltage, thus the system can quickly respond to transient change of the input voltage or the output signal and provide stable output. Output voltage information or/and input voltage information can be fed back to a control loop, thus the system can quickly obtain a switching duty cycle which allows the system to operate in a state close to steady, and dynamic response speed of the system is fast.

Abstract: Disclosed is a high-efficiency flyback converter and a control method thereof. The flyback converter comprises: a transformer; a first switch transistor and a second switch transistor; a resonant capacitor; a control circuit, for controlling the second switch transistor to be turned on for a first time before the first switch transistor is turned on during a switching cycle, controlling the second switch transistor to maintain turn-off state during a first time stage, to control energy transmission between primary and secondary sides to include two time stages during a switching cycle, the first time stage lasts for a set time period during a freewheeling process. The present disclosure allows the main switch transistor to realize zero-voltage turn-on, thus reducing conduction loss of the primary and the secondary sides, reducing ripples of an output voltage and a current of the secondary side, and being beneficial to improving operating efficiency.

Abstract: Disclosed is a soft switch control circuit and a flyback converter, comprising a primary edge part and a secondary edge part, and obtaining a trigger pulse signal according to a pre-turning on signal of a main switch transistor before the main switch transistor is turned on. The trigger pulse signal is transmitted to the secondary edge part by an isolation module to control the switch at a secondary edge circuit to conduct, to reduce source-drain voltage of the main switch circuit of the primary edge, to make the main switch transistor to turn on when the source-drain voltage is near zero voltage. The switch of the secondary edge circuit is a synchronous rectifying switch transistor or a discharge switch transistor connected at two ends of the synchronous rectifying switch transistor.

Abstract: Disclosed is a protection circuit of a flyback converter and a control method. The protection circuit comprises: an active discharge module, connected to at least one end of a first capacitor in a resonance circuit of the flyback converter to provide a discharge path, and controlling turning-on and turning-off of the discharge path according to the discharge enable signal; in a normal work state, the discharge path is disconnected, the first capacitor works as a resonance capacitor; before the flyback converter is restarted, the discharge path is turned on for a predetermined time period to release charges of the first capacitor, a resonance current after the flyback converter is restarted is reduced to a safe work current of the second switch transistor. Charges stored in the first capacitor can be discharged to release before the flyback converter is restarted to reduce the resonance current and enhance system stability and security.

Abstract: Disclosed is a protection circuit of a flyback converter and a control method. The protection circuit comprises: an active discharge module, for providing a discharge path between a first current terminal and a second current terminal of a switch transistor in a resonance circuit, and controlling turning-on and turning-off of the discharge path according to a discharge enable signal; in the normal work state of the flyback converter, the discharge path is disconnected, the resonance circuit works, before the flyback converter is restarted, the discharge path is turned on for a predetermined time period to release charges stored in the resonance circuit, and the resonance current after the flyback converter is restarted is reduced to the safe work current of the second switch transistor. The resonance current is discharged before the flyback converter is restarted, thus reducing the resonance current and enhancing system stability and security.

Abstract: A supply circuit and a switched mode power supply (SMPS) are provided. The supply circuit includes a first capacitor, a second capacitor, and a charging-discharging control circuit; the first capacitor includes a first terminal connected to a switching node, and a second terminal for providing a first supply voltage; the second capacitor includes a first terminal connected to a reference ground or a first potential terminal under control of the charging-discharging control circuit, and a second terminal for providing a second supply voltage; and according to a charging-discharging enable signal, the charging-discharging control circuit charges the second capacitor in a first time period and discharges the second capacitor in a second time period.

Abstract: A light source driving circuit and a communication device for display system are provided. The communication device includes a control unit and at least one string light source driving circuit. The control unit includes an output interface for transmitting control commands or data and a data reading back input interface. Each string light source driving circuit includes a plurality of light source driving circuits, and each light source driving circuit interface includes a serial input interface, a serial output interface, parallel interfaces, and at least one current output interface. The serial input interface and serial output interface of the plurality of light source driving circuits are cascaded with each other as a first channel of the control commands or data transmission. The parallel interfaces of each driving circuit in the plurality of driving circuits are coupled with each other as a second channel of the control commands and data transmission.

Abstract: A light source driving circuit and a communication device for a display system are provided. The communication device includes a control unit and at least one string light source driving circuit. The control unit includes an output interface for transmitting the control commands or data and a reading back data input interface. Each string light source driving circuit includes a plurality of light source driving circuits. The control unit transmits the control commands or data to the first light source driving circuit of each string light source driving circuit through the output interface. The first driving circuit takes out the commands or data required at the current stage after receiving the control command or data, and then repackages the commands or data of the remaining driving circuits, and transmits the repackaged data packet through the serial output interface and the parallel interfaces or the parallel interfaces.

Abstract: A control circuit and control method for a switched capacitor converter (SCC) are provided. An adjustment circuit makes adjustment with a small pull-down current, such that two terminal voltages of a flying capacitor are consistent with an output voltage. Before the SCC works formally for voltage conversion, the two terminal voltages of the flying capacitor are the same as the output voltage.

Abstract: An X-capacitor discharge method applied to a switched-mode power supply, wherein the switched-mode power supply comprises an X-capacitor, a rectifier circuit and a switching circuit; the X-capacitor discharge method comprises: arranging a first diode, wherein an anode of the first diode is connected to a first end of the X-capacitor, and a cathode of the first diode is configured as a first node; when it is detected that a voltage of the first node is higher than a first voltage threshold, pulling down the first node through a first sampling current, and performing a timing; and if a time for which the voltage of the first node continues to be higher than the first voltage threshold reaches a first threshold time, pulling down the first node through a first pull-down current. An X-capacitor discharge circuit applied to the switched-mode power supply is provided.

Abstract: A dimming method and a dimming circuit for driving LED load are provided. The dimming circuit includes a power stage circuit, and the power stage circuit includes a power switch transistor. After the power stage circuit enters the DCM working mode, it obtains a first integral value according to the inductance current in a switch period of the power switch transistor, and obtains second time according to the first integral value and a duty cycle of a PWM dimming signal; when the switch period reaches the second time, the power switch transistor is controlled to be turned on to start the next switch period; a first upper limit voltage is set to a fixed voltage; the power switch transistor is controlled to be turned off when a sampling signal of the inductance current representing the inductance current of the power stage circuit reaches the first upper limit voltage.

Abstract: A flyback switching circuit and control method thereof is disclosed, by setting a reference value greater than zero configured for controlling a turn-off time of a first transistor of the flyback switching circuit, a drain-source voltage of a main power transistor of the flyback switching circuit is consistent with the reference value greater than zero before the main power transistor is turned on, so that a turn-on power consumption of the main power transistor is reduced and a system efficiency is improved.

Abstract: Disclosed is an LED driver circuit, a multi-wire communication device and a method for an LED display system. The device comprises a controller providing at least one of a configuration data packet, a brightness data packet, and a display data packet; the LED driver circuits, wherein the LED driver circuits are cascaded to provide a first data channel using first data ports and second data ports, the LED driver circuits are connected in parallel to provide a second data channel using third data ports. The device relays an enable signal or an address data packet stage by stage using the first data channel, transmit at least one of the configuration data packet, the brightness data packet and the display data packet in parallel using the second data channel. The number of the cascaded LED driver circuits can be infinite, the number of data wires is reduced, data rate is increased.