Patents
Literature
Patsnap Eureka AI that helps you search prior art, draft patents, and assess FTO risks, powered by patent and scientific literature data.

38 results about "Flyback topology" patented technology

The flyback topology is based on a buck-boost topology, with the transformer providing isolation and, if needed, voltage transformation by turns ratio.

Two-Transistor Flyback Topology With Rompower High Efficiency Passive Clamp

A two-transistor flyback topology in which a portion of leakage inductance energy in the transformer is extracted and used to obtain zero voltage switching on both switching elements in any operating conditions, and in which a third low power switch eliminates parasitic oscillations and allows an operation at a determined frequency. In this topology, there are no switching losses and there are no spikes or glitches in any switching node, eliminating the need for snubbers. This topology is an “ideal two transistor flyback topology.”
Owner:ROMPOWER TECHNOLOGY HOLDINGS LLC

Flyback topology micro inverter system and active power control method

The invention discloses an active power control method for a flyback topology micro inverter system, and the method comprises the steps: calculating the load power of a load end through a current sampling module, and carrying out the uniform power distribution of a PV primary side branch when the load power is greater than or equal to the rated power of an inverter system; when the load power is smaller than the rated power of the inverter system, the PV primary side branch is closed step by step according to the load power difference; and when the load power is smaller than the minimum set power sum, one PV primary side branch is kept to operate. When the load power is smaller than the minimum set power, all the PV primary side branches are closed, and when the load power is larger than the minimum set power of the PV primary side branch with the lowest minimum set power, the system is started. According to the invention, multi-path regulation and control can be realized, and the control stability of the system is improved. And uniform distribution control, step-by-step adjustment distribution control, minimum power control and active power control are relatively flexible and efficient, so that the service life of the system is remarkably prolonged, and the reliability of the system is remarkably improved.
Owner:SUZHOU HYPONTECH CO LTD

Flyback topology multipath constant voltage power supply circuit with multiple transformers coupled in series

The utility model provides a flyback topology multipath constant voltage power supply circuit with a plurality of transformers coupled in series, which comprises a flyback topology circuit structure and at least one topology closed-loop circuit structure cascaded with the flyback topology circuit structure through a secondary transformer, the flyback topology circuit structure comprises a primary side closed-loop circuit structure located on the primary side of the main transformer and a secondary side closed-loop circuit structure located on the secondary side of the main transformer, and a first coupling winding on the secondary side of the main transformer is magnetically coupled with a second coupling winding on the primary side of the secondary transformer. And the dotted terminals of the first coupling winding and the second coupling winding are arranged on the same side, so that the defects of traditional multi-group transformer and multi-closed-loop system control are overcome, and a solution with low cost and high performance is provided.
Owner:HANGZHOU YOUTE POWER CO LTD

Electric quantity distribution protection system of mobile phone power adapter

The invention discloses an electric quantity distribution protection system of a mobile phone power adapter, which relates to the technical field of adapter operation monitoring, and comprises the following steps: carrying out intelligent dynamic current distribution and voltage calibration, and responding to voltage fluctuation; predicting an equipment charging curve, matching the dynamic load, and reducing the chemical stress of the battery; based on load dynamic mode topology switching, the flyback topology design is adopted to reduce loss during light load, and the quasi-resonance mode is switched to improve efficiency during heavy load; through hardware multiplexing design, multi-protocol parallel processing is realized, and when wired and wireless charging devices are connected at the same time, the adapter dynamically distributes power; a magnetic core material and a winding structure are optimized; the switching frequency is reduced through a pulse width modulation controller, and modeling is carried out on historical temperature data; and identifying metal foreign matters and outputting alarm information. Through multi-module collaborative optimization, the technical defects of a traditional adapter under complex working conditions are overcome, the user experience is improved, and the equipment safety is guaranteed.
Owner:SHENZHEN SUNNY SHI JI TECH CO LTD

Voltage stabilization control circuit applied to multi-path output flyback topology

The invention discloses a voltage stabilization control circuit applied to multi-path output flyback topology, which relates to the field of multi-path output auxiliary power supply, and comprises a transformer, a primary side driving switch circuit, a feedback control loop and a plurality of groups of secondary side output loops and load simulation circuits, a load simulation circuit composed of a diode, a capacitor and a resistor is introduced into a key secondary output loop, a feedback sampling point is moved to the capacitor, and the time constant of the load simulation circuit is matched with the load time constant of each output loop through fine design. By means of the design, the controller can be intelligently guided to adjust the duty ratio, it is ensured that under all load conditions, output voltages of all paths can be kept above rated values, system downtime is fundamentally avoided, and the reliability of the system is improved. According to the circuit, the reliability and the load adaptability of the power supply are remarkably improved with extremely low cost.
Owner:杭州飞思特电源科技有限公司

Power supply circuit of display system

The utility model provides a power supply circuit of a display system, in a flyback topology circuit of the power supply circuit, an input end of an output unit is connected with a rectification circuit through a transformer and an input unit in sequence, and two output ends of the output unit are respectively used as two output ends of the flyback topology circuit; the input unit and the output unit are both provided with a controller; the two controllers are connected through an isolation optocoupler; the output unit is provided with at least two switch tubes, the switch tubes are controlled by the controller, and the conduction states of the two switch tubes influence the output states of the first output end and the second output end of the output unit; namely, in the output unit, energy transmitted by the flyback topology circuit is balanced by controlling two switching tubes, one-path constant-voltage output and one-path constant-current output are realized, the constant-voltage and constant-current requirements of the LED matrix and the mainboard are met on the basis of not increasing a Buck / Boost circuit, and a power supply circuit is simple and low in cost.
Owner:SHENZHEN KTC TECH CO LTD

Variable load circuit applied to flyback constant current driving and implementation method thereof

The invention belongs to the technical field of flyback constant current driving, and relates to a variable load circuit applied to flyback constant current driving and an implementation method of the variable load circuit. The invention aims to solve the technical contradiction that the existing fixed resistor dummy load cannot give consideration to the LED turn-off function, the high full-load efficiency and the low-load power consumption at the same time. The circuit comprises a flyback topology circuit unit and a variable load circuit unit, the variable load circuit automatically switches impedance according to an output voltage: when the output voltage is lower than a threshold value, the impedance is low, excess energy in a turning-off state is efficiently consumed, and stable turning-off of an LED is ensured; when the output voltage is higher than the threshold, high impedance is presented, and invalid power consumption is remarkably reduced. An additional control circuit is not needed, self-adaptive adjustment is achieved through pure hardware logic, compatibility with an existing flyback topology is high, a fixed resistance dummy load can be directly replaced, the LED adjusting and extinguishing function is guaranteed, meanwhile, the driving full-load efficiency is improved, and the no-load power consumption is reduced.
Owner:SICHUAN HONGRUI ELECTRIC CO LTD

Inverter topology circuit, inverter and photovoltaic power generation system

The invention discloses an inverter topology circuit, an inverter and a photovoltaic power generation system. The inverter topology circuit comprises an input circuit, a forward and reverse excitation circuit and an output circuit, the input circuit comprises a photovoltaic panel and a first capacitor, the forward and reverse excitation circuit comprises a first branch circuit, a second branch circuit and a second capacitor; wherein the first branch is connected with the first capacitor in parallel, the second branch is connected with the first branch in parallel, and the second capacitor is connected with the second branch in parallel; the first branch circuit and the second branch circuit are both forward-flyback topological circuits and are alternately conducted; the output circuit comprises a first switch group, a second switch group and an external load; wherein the first switch group is connected with the second capacitor in parallel, the second switch group is connected with the first switch group in parallel, one end of the external load is connected with the first switch group, and the other end of the external load is connected with the second switch group. By adopting a double-transformer structure and an interleaved parallel forward-flyback topological circuit, the power density is increased, ripples are reduced, and the reliability is improved.
Owner:PIONEER ORIGINAL (SHANGHAI) NEW TECHNOLOGY RESEARCH CO LTD

Flyback topology circuit and circuit board

The embodiment of the invention discloses a flyback topology circuit and a circuit board, and relates to the field of power circuits. The flyback topology circuit provided by the invention comprises a resonant conversion LLC module, a first rectification filtering module, a first load module, a switching module, a flyback module, a second rectification filtering module, a voltage regulation module and a second load module. Based on the circuit structure provided by the invention, when the voltage value of the first working voltage is greater than the voltage value of the second working voltage, the switching module is switched on to enable the second load module to work based on the first working voltage, or when the voltage value of the first working voltage is smaller than or equal to the voltage value of the second working voltage, the switching module is switched off to enable the second load module to work based on the second working voltage. And the second load module works based on the second working voltage. According to the embodiment of the invention, the power conversion efficiency of the flyback topology circuit can be improved, and the flyback topology circuit is simple in structure.
Owner:GUANGZHOU SHIYUAN ELECTRONICS CO LTD +1

Double-transistor flyback topology circuit structure of audio power supply module

The utility model relates to the field of audio power supplies, in particular to a double-transistor flyback topology circuit structure of an audio power supply module, which is characterized by comprising a double-transistor flyback switching circuit and a voltage conversion circuit, and the output end of the double-transistor flyback switching circuit is electrically connected with the input end of the voltage conversion circuit. According to the utility model, the output power and efficiency are improved, the peak voltage and the peak current can be effectively controlled, the ripples at the output end can be reduced, and the circuit is especially suitable for equipment sensitive to the ripples.
Owner:KOBBLE DIGITAL ELECTRONICS

Bridge flyback topology circuit and switching power supply

The present invention provides a power module, a bridge flyback topology circuit and a switching power supply, including: an upper tube and a lower tube are gallium nitride power tubes; the drain of the upper tube is connected to a DC input voltage, the source is connected to the cathode of a first diode, and the gate receives a first drive signal; the first diode, the anode is grounded; the second diode, the cathode is connected to the DC input voltage, the anode is connected to the drain of the lower tube; the source of the lower tube is grounded, and the gate is connected to the second drive signal; an output transformer, the primary winding is connected between the source of the upper tube and the drain of the lower tube, and the secondary winding is connected to the output circuit. The present invention uses the reverse conduction characteristics of cascaded gallium nitride and two high-efficiency diodes to build a bridge circuit, effectively absorbs the energy generated by leakage inductance, has a small size, low cost, and low power consumption; and effectively solves the problems of common-mode interference and standby power consumption.
Owner:DALIAN XINGUAN TECH INC +1

A determination circuit for output power of a flyback topology

The utility model discloses a kind of determination circuits of output power of flyback topology structure, comprising: the detection end of synchronous rectification mos pipe SR end is connected to resistance R1 low end, parallel resistance R2 between detection end and resistance R1, detection end includes diode D1 and bias voltage source V B Diode clamping circuit composed of diode D1 and diode D2, triode Q1 and triode Q2 compose low-connection current mirror, triode Q2 connects dynamic voltage;Low-connection current mirror delivers detection current mirror image to resistance R3;Voltage comparator T1 is based on detection current and resistance R3 output detection signal, rising edge counter J1 determines the rising edge frequency of detection signal, output determination result. Thus, only need to add a resistance on existing drive circuit, can be compared by voltage comparator output detection signal containing rising edge and falling edge, according to this determination switching frequency, realize load determination, device demand is greatly reduced, and detection accuracy is greatly improved.
Owner:ZHUHAI YINGJIXIN SEMICON CO LTD

Full-isolation signal conditioner

The invention discloses a full-isolation signal conditioner which comprises a power supply module, and an input module, a programmable signal configuration module and an output module which are connected with the power supply module, isolation modules are arranged between the input module and the programmable signal configuration module, between the programmable signal configuration module and the output module and between the power supply module; the power supply module comprises an open-loop power supply and a primary side noise feedback module; the open-loop power supply adopts a flyback topological structure; the primary side noise feedback module comprises a noise sampling circuit and a digital controller, and the isolation module comprises at least one independent isolation unit. The structure of the signal isolation conditioner is more flexible and simpler, and an integrated solution of high isolation, low crosstalk and multi-signal type dynamic configuration is realized on the premise of low cost.
Owner:SHANXI XINBOXIANG TECH CO LTD

Winding multiplexing soft switching flyback circuit

The winding multiplexing soft switching flyback circuit comprises an energy storage unit, a main control unit, a switch unit, a VCC power supply soft switching unit, a sampling unit, a high-frequency transformer unit and a rectification output unit. According to the utility model, the second primary winding of the flyback switching power supply is used as the main power winding, the VCC power supply winding and the soft switching auxiliary winding to supply power to the main control unit and realize the soft switching of the main switch, compared with the conventional flyback topology, the flyback topology circuit can realize the ZVS of the main power tube, and can realize the soft switching of the main switch. Meanwhile, a soft switch auxiliary winding does not need to be added, loss is reduced, transformer primary side framework pins can be effectively reduced, and therefore the size of the transformer is reduced.
Owner:MORNSUN GUANGZHOU SCI & TECH

Switching power supply system based on flyback topology

The invention discloses a switching power supply system based on flyback topology, and the system comprises an input protection and rectification module which comprises a fuse F1, an EMI filter circuit, a rectifier bridge D1 and a capacitor C3, and is used for carrying out the overcurrent protection, electromagnetic interference suppression and full-wave rectification of 220V AC signal input, and converting a filtered AC signal into a 300-400V high-voltage DC signal; the flyback power conversion module comprises a PWM (Pulse Width Modulation) controller U1, an MOS (Metal Oxide Semiconductor) tube Q1, a high-frequency transformer T, a resistor R1, a resistor R2, a diode D2 and a capacitor C4, and is used for adjusting the switching duty ratio of the MOS tube Q1 through the PWM controller U1 and controlling the energy storage and release of a primary winding of the high-frequency transformer T1; and the output rectifying and filtering module comprises a diode D3, a capacitor C5 and a filtering module and is used for rectifying and filtering signals output by the secondary side of the transformer. The system solves the problems of large ripple, insufficient power and poor reliability in the prior art.
Owner:NAWEI SEMICONDUCTOR TECHNOLOGY (HEFEI) CO LTD

Transitional USB PD (power delivery) dual port receptacle with smart bypass circuit

A transitional USB receptacle has one USB PD port and one USB-C port (non-PD). The receptacle includes flyback topology for AC / DC conversion, a bypass circuit, a buck converter, and a USB controller that determines the voltage demands of external devices connected to the USB-C and PD ports. The flyback topology uses a transformer with two sets of windings that produce different output voltages. The bypass switch is configured to ensure that only voltage signals under 10V are input to the buck converter, resulting in a different one of the transformer output voltages being input to the buck converter under different load demands. This enables the buck converter to more efficiently produce a 5V at the USB-C port when the USB PD port needs to simultaneously supply either 15V or 20V, and also enables the buck converter to more efficiently produce a 5V or 9V output at the USB PD port.
Owner:EATON INTELLIGENT POWER LTD

Motor driving circuit based on pre-charging and multi-path flyback power supply

A motor driving circuit based on pre-charging and multipath flyback power supplies belongs to the field of motor driving, and comprises high-voltage DC input terminals, a pre-charging buffer unit, a multipath isolation power supply conversion unit and a motor driving unit, the pre-charging buffer unit is connected between the input terminals, current-limiting charging is carried out on a bus capacitor through a pre-charging resistor, and the multipath isolation power supply conversion unit is connected with the motor driving unit. The power-on impact current is suppressed; the multi-path isolation power supply conversion unit adopts flyback topology, bus voltage is converted and isolated into multi-path independent low-voltage direct-current power supplies, a closed-loop voltage stabilizing circuit is configured for at least one path of output, and the motor driving unit obtains driving power from a bus capacitor and obtains a control power supply from the multi-path isolation power supplies, so that efficient and reliable driving of a motor is realized; according to the invention, the problems of high-voltage power-on impact and multi-path isolation power supply are solved, and high reliability, high integration and strong anti-interference capability are realized.
Owner:FUJIAN AISKE NEW ENERGY TECH CO LTD

An OTP balancing protection circuit

The application provides an OTP balance protection circuit, and relates to the field of protection circuits.The OTP balance protection circuit comprises a flyback topology main circuit, a VCC power supply circuit, an OTP protection pin control circuit and an OTP balance control circuit.The utility model discloses a single point detection is realized to many devices balance protection, reduces circuit complexity and cost;the OTP protection point is adaptively adjusted, and the reliability under different input voltages and load conditions is ensured;the insulation problem of cross connection is avoided, and the design is simplified;the OTP function is closed when the load is light, and the risk of false triggering is reduced;the circuit can reliably protect various power devices under different input voltages and different load currents.
Owner:SHENZHEN RUIBIDA TECH

Primary side feedback circuit

The invention provides a primary side feedback circuit which comprises a transformer primary side module, a mirror current source module, an operational amplifier module, a PWM control module, a switch module and a transformer secondary side module, the transformer primary side module is connected with the mirror current source module, and the operational amplifier module is connected with the mirror current source module. The PWM control module is connected with the operational amplification module, the switch module is respectively connected with the transformer primary side module and the PWM control module, and the transformer secondary side module is in coupling connection with the transformer primary side module. According to the characteristic that the voltage on the primary winding of the transformer has correlation with the output voltage after the primary MOS tube is turned off, the constant current source sampling circuit is used for sampling the voltage, and a signal of the voltage is fed back to the PWM controller, so that the MOS tube Q2 is controlled to be turned on, and the purpose of stabilizing the output voltage is achieved; the flyback topology feedback circuit solves the problems that an existing flyback topology feedback circuit is complex in circuit structure, multiple in component and limited in reliability and application environment, the reliability of the circuit is improved, and the use scene of the circuit is expanded.
Owner:SHENZHEN ZHENHUA MICROELECTRONICS

LED backlight driving circuit controlled by N-type MOSFET

The invention discloses an LED backlight driving circuit controlled by an N-type MOSFET. The primary side of a flyback transformer of the driving circuit is connected with a primary side switching tube; a first winding in a secondary side winding of the flyback transformer is connected with a first rectification filter circuit, and the output end of the first rectification filter circuit forms a voltage stabilization output end to supply power to a system mainboard; one end of a second winding in the secondary side winding is connected with the cathode of a protection diode, and the anode of the protection diode is grounded; the drain electrode of the first N-type MOSFET is connected with the other end of the second winding, and the source electrode of the first N-type MOSFET is connected with the positive electrode of the light bar; the grid electrode of the first N-type MOSFET is connected with a grid electrode driving circuit; the power supply end of the PWM control chip is connected with the voltage stabilization output end, the output pin of the PWM control chip is connected with the grid drive circuit, and the feedback pin of the PWM control chip is connected with the current sampling end of the LED light bar. According to the invention, integration of voltage stabilization and constant current output is realized in the single-stage flyback topology.
Owner:TPV ELECTRONICS (FUJIAN) CO LTD

240W-level electric vehicle program control charger circuit

The utility model discloses a 240W grade electric vehicle program control charger circuit, comprising a low pass filter circuit module, a rectifier bridge, an RCD absorption circuit module, a transformer T1, a diode D4, a relay FJ1, a feedback voltage loop module, a feedback current loop module and the like, the 240W grade electric vehicle program control charger circuit uses a chip U10 as a core to form a flyback topology, uses a PQ3230 transformer to isolate output, and uses a relay FJ1 as a relay FJ1. And the relay controls output, and the feedback loop is matched with the voltage loop and the current loop to control the voltage and the current respectively so as to output the desired voltage and the desired current. Compared with the prior art, the charger has the advantages of being small in heat productivity, high in switching speed and capable of working without a fan, has the functions of over-temperature protection, over-power protection and overvoltage and undervoltage protection, and enables the safety of the charger to be greatly improved.
Owner:GUANGZHOU KINGPIN IND CO LTD

PWM controller with fixed turn-off time, control chip and control circuit

The invention relates to the technical field of switching power supply control, and discloses a PWM (Pulse Width Modulation) controller with fixed turn-off time, a control chip and a control circuit, the PWM controller comprises a power supply unit, a band-gap reference unit, an MOS (Metal Oxide Semiconductor) driving unit, a clamping unit, a triangular wave generator, a comparator CMP1, a comparator CMP2, an SR latch and an internal resistor Rn; according to the PWM controller structure, the turn-off time of peripheral MOS transistors driven by the MOS driving unit is fixed in the actual use process, the PWM controller structure is good in forward topology overload consistency when applied to forward topology, the maximum load is slightly influenced by input voltage fluctuation, and the reliability of forward is improved. When the method is applied to flyback topology, current disturbance can be automatically eliminated without slope compensation when the duty ratio exceeds 50%.
Owner:JIANGSU YUANWEI SEMICON TECH CO LTD

Wide-voltage input high-efficiency conversion device based on full-bridge or half-bridge resonance forward and reverse excitation topology and control method

The invention discloses a wide-voltage input high-efficiency conversion device based on full-bridge or half-bridge resonance forward and reverse excitation topology and a control method, which break through the efficiency and adaptability bottlenecks of the traditional wide-voltage conversion device through dual-transformer forward and reverse excitation mode collaborative switching, resonance network soft switching optimization, magnetic circuit air gap design and adaptive frequency control. The device supports 20V-1000V ultra-wide input voltage, the peak efficiency is greater than or equal to 96.5%, and the device has the advantages of high power density, low loss, strong reliability and the like, and can be widely applied to the fields of industrial power supplies, new energy automobiles, aerospace and the like.
Owner:BEIJING BODIAN ELECTRIC CO LTD

AED high-voltage power supply system based on LLC resonant conversion and voltage multiplication integration and control method

PendingCN122890879AMOSFETSoftware engineering
The application discloses an AED high-voltage power supply system and a control method based on LLC resonant conversion and voltage multiplication integration, which comprises a main controller module, an LLC-voltage multiplication power supply module and a switch control module. The main controller module interacts with the LLC-voltage multiplication power supply and the switch control module and receives voltage and current feedback signals. The LLC-voltage multiplication power supply module adopts a topology of cascading a resonant conversion unit and a Cockcroft-Walton voltage multiplier, cooperates with a Core-in-Board planar transformer, and replaces a scheme of a traditional transformer and a flyback topology plus high-voltage rectification. Leakage inductance of the planar transformer is utilized for resonance, and extra resonant inductance of the LLC is removed. In combination with a soft start and a constant-current-constant-voltage phased control strategy, stress of a switch tube is reduced. A resonant cavity transmits energy in a sinusoidal wave, realizes full-process zero-voltage switching (ZVS) of a primary MOSFET, and reduces switch loss. The low-turn primary side (3T) of the planar transformer and the design of the Faraday shielding layer reduce copper loss and EMI electromagnetic interference, improve power conversion efficiency, system integration and defibrillation reliability.
Owner:WEDING TECHNOLOGY (SUZHOU) CO LTD

A power distribution protection system for mobile phone power adapter

The present invention discloses a power distribution protection system for a mobile phone power adapter, which relates to the technical field of adapter operation monitoring. The system includes: performing intelligent dynamic current distribution and voltage calibration to respond to voltage fluctuations; predicting the device charging curve and matching the dynamic load to reduce battery chemical stress; switching the load-based dynamic mode topology, using a flyback topology design to reduce losses under light loads and switching to a quasi-resonant mode to improve efficiency under heavy loads; implementing multi-protocol parallel processing through hardware reuse design, and dynamically distributing power when simultaneously connected to wired and wireless charging devices; optimizing the magnetic core material and winding structure; reducing the switching frequency through a pulse width modulation controller and modeling historical temperature data; and identifying metal foreign objects and outputting alarm information. Through multi-module collaborative optimization, the system addresses the technical shortcomings of traditional adapters under complex working conditions, improving user experience and ensuring device safety.
Owner:SHENZHEN SUNNY SHI JI TECH CO LTD

An 800v high-voltage input dual-tube flyback auxiliary power supply device

PendingCN122339259AMOSFETTransformer
This invention relates to the field of high-voltage power conversion technology, and discloses an 800V high-voltage input dual-transistor flyback auxiliary power supply device. The device includes an input filtering module, a dual-transistor flyback power conversion module, a control and drive module, an output rectification and filtering module, and a protection module. The core of this invention lies in utilizing the clamping characteristics of the dual-transistor flyback topology to precisely limit the voltage stress of the power switching transistors (Q1, Q2) to an 800V input voltage level, thereby achieving a breakthrough by using industrial-grade MOSFETs with a 900V withstand voltage rating, avoiding the need for ultra-high withstand voltage (>1600V) special devices required in single-transistor solutions. Combined with a symmetrical transformer primary winding design, EE-type magnetic core air gap optimization, and an isolated drive scheme, this invention solves the problems of high cost, low efficiency, and complex structure inherent in existing 800V auxiliary power supplies. It features low voltage stress, high conversion efficiency, compact structure, low cost, and high reliability, and can be widely adapted to 800V high-voltage platforms such as new energy vehicles and energy storage systems.
Owner:CHUANGSHENG TECHNOLOGY (SHIYAN) CO LTD

Winding multiplexing flyback circuit

The utility model discloses a winding multiplexing flyback circuit which comprises an energy storage unit, a main control unit, a switch unit, a VCC power supply unit, a sampling unit, a high-frequency transformer unit and a rectification output unit. The second primary winding serves as the main power winding and also serves as the VCC power supply winding to supply power to the main control unit, compared with a conventional flyback topology, one VCC power supply winding can be omitted, the size of a high-frequency transformer framework is reduced, meanwhile, the coil saturation is optimized, and the overall performance of the high-frequency transformer is improved. And meanwhile, the cost of the high-frequency transformer is reduced.
Owner:MORNSUN GUANGZHOU SCI & TECH

Variable load circuit applied to flyback constant current driving and implementation method thereof

The present application belongs to the technical field of flyback constant current driving, and relates to a variable load circuit applied to flyback constant current driving and an implementation method thereof. The present application aims to solve the technical contradiction that the existing fixed resistance dummy load cannot simultaneously consider the LED dimming function and high full-load efficiency and low no-load power consumption. The circuit comprises a flyback topology circuit unit and a variable load circuit unit. The variable load circuit automatically switches impedance according to the output voltage: when the output voltage is lower than the threshold value, low impedance is presented, the excess energy in the dimming state is efficiently consumed, and the LED is ensured to be stably extinguished; when the output voltage is higher than the threshold value, high impedance is presented, and the invalid power consumption is significantly reduced. Without an additional control circuit, adaptive adjustment is realized through pure hardware logic, the compatibility with the existing flyback topology is high, and the fixed resistance dummy load can be directly replaced, so that the LED dimming function is ensured, the driving full-load efficiency is improved, and the no-load power consumption is reduced.
Owner:SICHUAN HONGRUI ELECTRIC CO LTD

A control method of a switching converter

The application discloses a control method of a switching converter, which sequentially enters a bootstrap capacitor pre-charging stage, a narrow pulse mode low-frequency starting stage, a narrow pulse mode volt-second balance frequency increasing stage and a complementary mode volt-second balance frequency increasing stage before entering a stable working state of a clamped asymmetric half-bridge flyback topology; on the one hand, the main power tube and the secondary rectifier tube can realize full-range zero-voltage switching and zero-current switching in the starting process, greatly improving the problems of large primary voltage and current stress and large secondary voltage stress of the existing clamped asymmetric half-bridge flyback topology during power-on starting; on the other hand, the starting speed of the switching converter can be effectively improved, and the smooth switching of the switching converter from soft-start voltage to loop feedback voltage for controlling the working of the switching converter can be ensured, and the current stress peak of the main power tube and the secondary rectifier tube caused by switching can be reduced; therefore, the safety and reliability of the switching converter can be improved.
Owner:MORNSUN GUANGZHOU SCI & TECH

Printer power supply with high overcurrent point

The utility model discloses a printer power supply with a high overcurrent point, which comprises an EMI filtering and rectifying circuit, a PFC control circuit, an LLC control circuit, an output rectifying and filtering circuit and a feedback circuit, and the PFC control circuit is used for boosting to improve the power factor of the power supply. By adopting LLC control, over three times of overcurrent points can be realized, the efficiency is relatively high, the voltage spike of the MOS tube and the diode is relatively small, and the safety is relatively high. Compared with a traditional flyback topology scheme power supply, the size of the whole power supply can be smaller; and the working characteristic of LLC control serving as a soft switch also enables the circuit to have better anti-electromagnetic interference performance. In the EMI filtering and rectifying circuit, the lightning stroke and surge protection effect is achieved through a fuse, a piezoresistor and a thermistor, and the electromagnetic infection resistance is further improved after filtering.
Owner:XIAMEN CITY KELI ELECTRONICS