LED high-magnification switching power supply driving circuit

Abstract

The invention relates to an LED high-magnification switching power supply driving circuit. The LED high-magnification switching power supply driving circuit comprises a main control module, an input module and an output module, the input module comprises a noise reduction unit and a first rectification unit, the noise reduction unit is electrically connected with the first rectification unit, and the first rectification unit is electrically connected with the main control module; and the output module is electrically connected with the main control module. According to the scheme provided by the invention, the anti-interference performance of the LED switching power supply can be improved, so that the output stability of the LED switching power supply is improved.

Description

Technical Field

[0001] The invention relates to the technical field of circuit design, and in particular to a high-rate switching power supply driving circuit for LEDs. Background Art

[0002] At present, LED lights are widely used, and they have the distinctive characteristics of environmental protection and energy saving. In the relevant technology, LED switching power supply is an important component to drive LED lights, which includes PWM dimming, analog dimming and digital dimming. However, the anti-interference ability of LED switching power supply in this way is poor, which easily leads to unstable power output of LED switching power supply, thus affecting the lighting effect of LED lights. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide an LED high-rate switching power supply driving circuit, which can improve the anti-interference performance of the LED switching power supply, thereby improving the stability of the LED switching power supply output.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The first aspect of the present application provides an LED high-rate switching power supply drive circuit, comprising: a main control module; an input module, the input module comprising a noise reduction unit and a first rectifier unit, the noise reduction unit is electrically connected to the first rectifier unit, and the first rectifier unit is electrically connected to the main control module; an output module, the output module is electrically connected to the main control module.

[0006] The input module includes an interface CN2 and a fuse F1 , and the fuse F1 is electrically connected to the interface CN2 .

[0007] The noise reduction unit includes a thermistor NTC1, a varistor TVR1, a capacitor CX1, a common mode inductor L1, a capacitor CY2 and a capacitor CY3. The first end of the varistor TVR1 is electrically connected to the fuse F1, the second end of the varistor TVR1 is electrically connected to the first end of the thermistor NTC1, the first end of the thermistor NTC1 is also electrically connected to the interface CN2, the second end of the thermistor NTC1 is electrically connected to the first end of the capacitor CX1, the second end of the capacitor CX1 is electrically connected to the common mode inductor L1, the first end of the capacitor CY2 is electrically connected to the common mode inductor L1, the second end of the capacitor CY2 is electrically connected to the first end of the capacitor CY3, and the second end of the capacitor CY3 is grounded.

[0008] The first rectifying unit includes a rectifying bridge tube DB1 and a rectifying bridge tube DB2 , and the rectifying bridge tube DB1 and the rectifying bridge tube DB2 are electrically connected to the common mode inductor L1 , respectively.

[0009] The first rectifier unit also includes a capacitor C15, a capacitor C16 and a capacitor CY1, the first end of the capacitor C15 is electrically connected to the first end of the capacitor C16, the second end of the capacitor C15 is electrically connected to the second end of the capacitor C16, the first end of the capacitor C16 is electrically connected to the rectifier bridge tube DB1, the second end of the capacitor C16 is electrically connected to the rectifier bridge tube DB2, and the first end of the capacitor CY1 is electrically connected to the first end of the capacitor C15.

[0010] The main control module includes a control unit, which includes a chip U3, a resistor R30 and a resistor R31. The first end of the resistor R30 is electrically connected to the rectifier bridge tube DB2, the second end of the resistor R30 is electrically connected to the first end of the resistor R31, and the second end of the resistor R31 is electrically connected to the chip U3.

[0011] The control unit also includes a resistor R24, a resistor R28, a resistor R15 and a capacitor C12, the first end of the resistor R24 ​​is electrically connected to the rectifier bridge tube DB2, the second end of the resistor R24 ​​is electrically connected to the first end of the resistor R28, the second end of the resistor R28 is electrically connected to the first end of the capacitor C12, the second end of the capacitor C12 is electrically connected to the first end of the resistor R15, and the second end of the resistor R15 is electrically connected to the chip U3.

[0012] The control unit further includes a capacitor C13, a first end of the capacitor C13 is electrically connected to the chip U3, and a second end of the capacitor C13 is grounded.

[0013] The control unit further includes a resistor R20 and a resistor R19, a first end of the resistor R20 is electrically connected to the chip U3, a second end of the resistor R20 is electrically connected to a first end of the resistor R19, and a second end of the resistor R19 is grounded.

[0014] The control unit also includes a capacitor C17 and a resistor R23, wherein a first end of the capacitor C17 is electrically connected to a first end of the resistor R23, and a first end of the resistor R23 is also electrically connected to the chip U3, a second end of the capacitor C17 is grounded, and a second end of the resistor R23 is electrically connected to a first end of the resistor R19.

[0015] Compared with the prior art, the present invention has at least the following advantages:

[0016] By setting up the noise reduction unit and the first rectifier unit, the noise reduction unit can filter out interference signals in the AC power grid to prevent crosstalk from affecting the output stability of the switching power supply. After receiving the voltage after the noise reduction unit has filtered out the interference, the first rectifier unit uses its larger heat dissipation area to solve the problem of output instability caused by temperature rise. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below.

[0018] Figure 1 It is a functional module diagram of an LED high-rate switching power supply driving circuit in one embodiment of the present invention;

[0019] Figure 2 FIG. 4 is a circuit diagram of an LED high-rate switching power supply driving circuit in an embodiment of the present invention. DETAILED DESCRIPTION

[0020] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.

[0021] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0022] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, or a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0023] At present, LED lights are widely used, and they have the distinctive characteristics of environmental protection and energy saving. In the relevant technology, LED switching power supply is an important component to drive LED lights, which includes PWM dimming, analog dimming and digital dimming. However, the anti-interference ability of LED switching power supply in this way is poor, which easily leads to unstable power output of LED switching power supply, thus affecting the lighting effect of LED lights.

[0024] In view of the above problems, the embodiments of the present application provide an LED high-rate switching power supply driving circuit, which can improve the anti-interference performance of the LED switching power supply, thereby improving the stability of the LED switching power supply output.

[0025] The technical solution of the embodiments of the present application is described in detail below with reference to the accompanying drawings.

[0026] See also Figure 1 A LED high-rate switching power supply driving circuit includes: a main control module 100, an input module 200 and an output module 300, the input module 200 includes a noise reduction unit and a first rectifier unit, the noise reduction unit is electrically connected to the first rectifier unit, and the first rectifier unit is electrically connected to the main control module 100; the output module 300 is electrically connected to the main control module 100.

[0027] It should be noted that the main control module 100 is used to output PWM duty cycle signals, the input module 200 is used to input 220V AC power, and the output module 300 is used to provide high-rate DC power to drive large LED products. Furthermore, by setting up a noise reduction unit and a first rectifier unit, the noise reduction unit can filter out interference signals in the AC power grid to prevent crosstalk from affecting the output stability of the switching power supply. After the first rectifier unit receives the voltage after the noise reduction unit has filtered out the interference, it uses its larger heat dissipation area to solve the problem of unstable output caused by temperature rise.

[0028] See also Figure 2 In one embodiment, the input module 200 includes an interface CN2 and a fuse F1, and the fuse F1 is electrically connected to the interface CN2.

[0029] It should be noted that the interface CN2 is used to connect an external 220V AC power as the starting voltage of the entire circuit. The live wire of the interface CN2 is connected to the fuse F1, which can be used for fuse protection when a large current appears in the input source to prevent the circuit from burning.

[0030] See also Figure 2 In one embodiment, the noise reduction unit includes a thermistor NTC1, a varistor TVR1, a capacitor CX1, a common mode inductor L1, a capacitor CY2 and a capacitor CY3, a first end of the varistor TVR1 is electrically connected to the fuse F1, a second end of the varistor TVR1 is electrically connected to a first end of the thermistor NTC1, a first end of the thermistor NTC1 is also electrically connected to an interface CN2, a second end of the thermistor NTC1 is electrically connected to a first end of the capacitor CX1, a second end of the capacitor CX1 is electrically connected to the common mode inductor L1, a first end of the capacitor CY2 is electrically connected to the common mode inductor L1, a second end of the capacitor CY2 is electrically connected to a first end of the capacitor CY3, and a second end of the capacitor CY3 is grounded.

[0031] It should be noted that the varistor TVR1 is connected to both ends of the live wire and the neutral wire of the interface CN2 to prevent it from being damaged by high-voltage surges during use in thunderstorms. It can also absorb large currents to protect the subsequent circuits. The thermistor NTC1 is connected to the neutral wire end of the interface CN2. The negative temperature thermistor NTC1 has a large resistance at room temperature, which prevents the LED product from being impacted by the peak voltage of the AC power when it is powered on, and plays a role in current limiting protection. The capacitor CX1 is connected to both ends of the interface CN2 to eliminate differential mode interference in the AC power. The common mode inductor L1 mainly suppresses the AC EMI radiation interference of the interface CN2, and at the same time, it is matched with capacitors CY2 and CY3 to eliminate differential mode interference, so that the LED product can filter out interference signals in the AC power grid through the noise reduction unit at the input end, and prevent crosstalk from affecting the output stability of the switching power supply.

[0032] See also Figure 2 In one embodiment, the first rectifier unit includes a rectifier bridge tube DB1 and a rectifier bridge tube DB2, and the rectifier bridge tube DB1 and the rectifier bridge tube DB2 are electrically connected to the common mode inductor L1 respectively.

[0033] It should be noted that the function of the first rectifier unit is to perform AD-DC conversion and filtering on the voltage after the noise reduction unit reduces the EMI interference signal, and output a smooth DC voltage. Furthermore, the rectifier bridge tube DB1 and the rectifier bridge tube DB2 are designed in parallel, and the power consumption and heat generation are evenly distributed on the two rectifier bridge tubes during operation. At the same time, the heat dissipation area of ​​the components is increased, so that the dual rectifier bridge tubes can exert their ultimate performance, effectively solving the problem of affecting the output stability after the product temperature rises.

[0034] See also Figure 2 In one embodiment, the first rectifier unit further includes a capacitor C15, a capacitor C16 and a capacitor CY1, a first end of the capacitor C15 is electrically connected to a first end of the capacitor C16, a second end of the capacitor C15 is electrically connected to a second end of the capacitor C16, a first end of the capacitor C16 is electrically connected to a rectifier bridge tube DB1, a second end of the capacitor C16 is electrically connected to a rectifier bridge tube DB2, and a first end of the capacitor CY1 is electrically connected to a first end of the capacitor C15.

[0035] It should be noted that capacitors C15 and C16 are connected in parallel to charge and discharge the pulsating voltage and then output a smooth voltage to the subsequent circuit. Capacitor CY1 is established between the grounding point with a higher temperature in the first rectifier unit and the grounding point with a lower temperature in the output module 300, which can reduce the EMC interference generated by the switching power supply, release and filter the high-frequency waves generated by the switching power supply, and effectively improve the stability of the power supply and reduce EMI interference.

[0036] See also Figure 2In one embodiment, the main control module 100 includes a control unit, which includes a chip U3, a resistor R30 and a resistor R31. The first end of the resistor R30 is electrically connected to the rectifier bridge tube DB2, the second end of the resistor R30 is electrically connected to the first end of the resistor R31, and the second end of the resistor R31 is electrically connected to the chip U3.

[0037] It should be noted that the model of the chip U3 may be LZC3106A. The resistors R30 and R31 play a role of current limiting to provide a startup voltage for the built-in circuit for the 1pin of the chip U3.

[0038] See also Figure 2 In one embodiment, the control unit also includes a resistor R24, a resistor R28, a resistor R15 and a capacitor C12, the first end of the resistor R24 ​​is electrically connected to the rectifier bridge tube DB2, the second end of the resistor R24 ​​is electrically connected to the first end of the resistor R28, the second end of the resistor R28 is electrically connected to the first end of the capacitor C12, the second end of the capacitor C12 is electrically connected to the first end of the resistor R15, and the second end of the resistor R15 is electrically connected to the chip U3.

[0039] It should be noted that the voltage output by the first rectifier unit passes through resistors R24, R28, and R15, and then the parallel capacitor C12 is connected to the 3pin of the chip U3, which can detect whether the chip U3 is undervoltage and play the function of input undervoltage protection.

[0040] See also Figure 2 In one embodiment, the control unit further includes a capacitor C13, a first end of the capacitor C13 is electrically connected to the chip U3, and a second end of the capacitor C13 is grounded. Specifically, the control unit further includes a resistor R20 and a resistor R19, a first end of the resistor R20 is electrically connected to the chip U3, a second end of the resistor R20 is electrically connected to a first end of the resistor R19, and a second end of the resistor R19 is grounded.

[0041] It should be noted that the 5pin of chip U3 is connected to capacitor C13 to ground to enable the frequency setting function, and the 4pin of chip U3 is connected through resistor R20 to adjust the operating frequency. At the same time, the external resistor R19 pull-down resistor provides an accurate 2V reference voltage to adjust the output voltage of the built-in converter of chip U3.

[0042] See also Figure 2 In one embodiment, the control unit also includes a capacitor C17 and a resistor R23, the first end of the capacitor C17 is electrically connected to the first end of the resistor R23, the first end of the resistor R23 is also electrically connected to the chip U3, the second end of the capacitor C17 is grounded, and the second end of the resistor R23 is electrically connected to the first end of the resistor R19.

[0043] It should be noted that the output module 300 includes a feedback unit, and the feedback unit includes an optocoupler transmitter U1, and the optocoupler transmitter U1 is electrically connected to the chip U3. Specifically, the 6pin of the chip U3 is connected to the electrical signal emitted by the optocoupler transmitter U1, and at the same time, the external resistor R23, the capacitor C17 and the resistor R19 compare the output with the 1.26V reference voltage of the built-in circuit of the chip U3, so as to realize the real-time feedback output of the switching power supply drive circuit, thereby controlling the output electrical signal of the chip U3.

[0044] Understandable, see Figure 2 In one embodiment, the main control module 100 also includes a transformer unit, and the control unit also includes a resistor R26, a resistor R29 and a capacitor C19, the first end of the resistor R26 is electrically connected to the chip U3, the second end of the resistor R26 is electrically connected to the first end of the capacitor C19, and the second end of the capacitor C19 is electrically connected to the first end of the resistor R29, the transformer unit includes a transformer T1, a diode D5, a resistor R14 and a capacitor C10, the second end of the resistor R29 is electrically connected to the transformer T1, the first end of the diode D5 is electrically connected to the transformer T1, the second end of the diode D5 is electrically connected to the first end of the resistor R14, the second end of the resistor R14 is electrically connected to the first end of the capacitor C10, and the second end of the capacitor C10 is grounded.

[0045] It should be noted that the 7pin external resistor R26, resistor R29 and capacitor C19 of chip U3 are connected to the FB pin of the N3 turn of transformer T1 to feedback voltage. Furthermore, the power supply circuit of chip U3 of the present application is output by the secondary coil of transformer T1, and is limited by resistor R14 after half-wave rectification by diode D5, and then connected to the 9pin of chip U3 after filtering out clutter signals to the ground by capacitor C10. Among them, the VCC supply voltage of chip U3 is about 17.69V.

[0046] Understandable, see Figure 2In another embodiment, the input module 200 further includes a PWM unit, the PWM unit including a MOS tube Q2, a resistor R21, a resistor R22, a transformer T2, a MOS tube Q1, a resistor R11, a resistor R12, a resistor R13, a resistor R18, a capacitor C14 and a diode D6, the MOS tube Q2 is electrically connected to the rectifier bridge tube DB1, the first end of the resistor R21 is electrically connected to the MOS tube Q2, the second end of the resistor R21 is electrically connected to the first end of the resistor R22, the second end of the resistor R22 is electrically connected to the chip U3, the MOS tube Q1 is electrically connected to the MOS tube Q2, the first end of the transformer T2 is electrically connected to the MOS tube Q2, and the second end of the resistor R22 is electrically connected to the chip U3. The first end of the resistor R11 is electrically connected to the first end of the resistor R12, the second end of the resistor R11 is electrically connected to the second end of the resistor R12, the first end of the resistor R13 is electrically connected to the first end of the resistor R12, the first end of the resistor R13 is electrically connected to the MOS tube Q1, the first end of the resistor R18 is electrically connected to the first end of the resistor R13, the second end of the resistor R18 is electrically connected to the chip U3, the first end of the capacitor C14 is electrically connected to the chip U3, and the second end of the capacitor C14 is grounded.

[0047] It should be noted that the first rectifier unit is connected to the PWM unit. Specifically, the MOS tube Q2 is a high-voltage MOS tube, and the MOS tube Q1 is a low-voltage MOS tube. The DC power converted by the first rectifier unit goes to the D pole of the MOS tube Q2, and the G pole of the MOS tube Q2 is connected to the 15pin of the chip U3 through the resistor R22. The S pole of the MOS tube Q2 is connected to the resistor R21 and returns to the G pole of the MOS tube Q2 to form a negative feedback signal. When the built-in circuit of the chip U3 sends a high-end timing signal, the MOS tube Q2 is turned on and connected to the D pole of the MOS tube Q1, and the 14pin of the chip U3 is connected between the MOS tube Q1 and the MOS tube Q2; on the contrary, when the built-in circuit of the chip U3 sends a low-end timing signal from the 12pin, the low-voltage tube of the MOS tube Q1 is turned on. The DC power of the first rectifier unit is given to the transformer T2 through the PWM unit, connected to the N1 turn of the transformer T1, and forms a loop with the capacitor C9. Under the condition that the output of the switching power supply driving circuit is not affected by the temperature rise, the voltage sampling circuit between the transformer unit and the main control unit uses alloy resistors, such as resistors R11, R12, and R13. Alloy resistors are not easily affected by temperature and change their resistance. After the transformer unit circuit is limited by resistor R18 and filtered by capacitor C14, it can accurately sample the current and transmit it back to the 10pin of chip U3 to detect the resonant current and perform overcurrent protection; and the N3 turn of transformer T1 mainly provides VCC voltage and OTP protection for chip U3. In addition, transformer T1 is connected to diode D6 and is connected to the 14pin of chip U3, thereby providing the functions of freewheeling, isolation, and output, so that the function of the main control module 100 can be fully utilized.

[0048] By matching the transformer unit with the MOS tube Q1 and MOS tube Q2 in the PWM unit, an LLC half-bridge resonant control circuit is formed. The high and low-end timing voltage signals output by the chip U3 are given to the PWM unit for operation. The high and low voltage MOS tubes cooperate with the LLC half-bridge resonant control circuit to store energy and charge and discharge the LLC resonant circuit, driving the N1 turn of the transformer T1 to perform current and voltage conversion, so that the primary and secondary of the transformer module have the same frequency input and output, effectively reducing the switching loss of the power supply, thereby improving the output efficiency of the transformer, and greatly improving the working efficiency of the switching power supply.

[0049] Understandable, see Figure 2 In another embodiment, in order to prevent high temperature from damaging the chip U3, the control unit further includes a resistor R25, a resistor R27 and a capacitor C18, a first end of the resistor R25 is electrically connected to a first end of the capacitor C18, a second end of the resistor R25 is electrically connected to the chip U3, a second end of the capacitor C18 is grounded, a first end of the resistor R27 is electrically connected to the capacitor C18, and a second end of the resistor R27 is electrically connected to the chip U3.

[0050] It should be noted that the 8pin of chip U3 is the OTP voltage connection pin, and the 9pin is the VCC voltage connection pin. A resistor R25 is set between them. Resistor R25 is a programmable resistor, and resistor R27 is a thermistor. By setting resistor R25, resistor R27 and capacitor C18, an over-temperature protection circuit is formed. When the LED product is in an abnormal state and the operating temperature soars, the chip U3 will autonomously enter the over-temperature protection function in advance, control the current output to prevent chip U3 from being damaged, and effectively avoid affecting other components.

[0051] Understandable, see Figure 2 In another embodiment, the output module 300 includes a second rectifier unit and an output terminal CN1, the second rectifier unit includes a diode D4, a diode D1, a diode D2, a diode D3, a capacitor C6, a capacitor C4, a capacitor C3, a capacitor C2, a resistor R3, a resistor R2, a resistor R1 and a lamp LED1, the diode D4, the diode D1, the diode D2 and the diode D3 are connected in parallel, the transformer T1 is electrically connected to the diode D4, the diode D1, the diode D2 and the diode D3 respectively, the first end of the capacitor C6 is electrically connected to the diode D4, the second end of the capacitor C6 is electrically connected to the diode D3, the first end of the capacitor C4 is electrically connected to the first end of the capacitor C6, the second end of the capacitor C4 is electrically connected to the second end of the capacitor C6, and the A first end of the capacitor C3 is electrically connected to a first end of the capacitor C4, a second end of the capacitor C3 is electrically connected to a second end of the capacitor C4, a first end of the capacitor C2 is electrically connected to a first end of the capacitor C3, a second end of the capacitor C2 is electrically connected to a second end of the capacitor C3, a first end of the resistor R3 is electrically connected to a first end of the capacitor C2, a second end of the resistor R3 is electrically connected to a second end of the capacitor C2, a first end of the resistor R2 is electrically connected to a first end of the resistor R3, a second end of the resistor R2 is electrically connected to a second end of the resistor R3, a first end of the resistor R1 is electrically connected to a first end of the resistor R2, a second end of the resistor R1 is electrically connected to a first end of the lamp LED1, a second end of the lamp LED1 is grounded, and the first end of the resistor R1 is also electrically connected to the output terminal CN1.

[0052] It should be noted that the second rectifier unit uses 4 parallel diodes D1, diode D2, diode D3, and diode D4 in a unidirectional conductive manner to perform "sinusoidal" AC-DC conversion, and converts the DC power with a phase difference of 180 degrees into a unidirectional smooth DC output through a secondary "AC-DC" conversion, and then outputs a stable high-rate DC voltage after filtering and coupling through capacitors C2, C3, C4, and C6. After the second rectifier unit outputs the voltage, the output fluctuation voltage value is taken through the resistor-capacitor voltage divider circuit, and then the optocoupler transmitter U1 of the feedback unit transmits the optocoupler signal to the control unit for voltage comparison, thereby realizing that the power drive circuit has an automatic adjustment control function, and uses the output fluctuation amplitude to control the timing signal output by the main control module 100. Furthermore, the high-rate voltage is modulated to a 24V voltage through resistors R2 and R3 current limiting and voltage reduction, and is connected to the output terminal CN1 for output. The output terminal CN1 supplies power to the LED device, wherein the output voltage 24V is stepped down by the resistor R1 to supply power to the lamp LED1. Therefore, it can be known from the status of the LED1 indicator that the switching power supply drive circuit outputs a 24V high-rate voltage after power is turned on.

[0053] Through the above settings, the interface CN2 is connected to the AC 220V to provide a starting voltage for the switching power supply drive circuit. First, the interference signal is filtered out to the ground through the noise reduction unit to prevent the crosstalk from affecting the stability of the switching power supply output, and also to resist the pulse interference generated by itself back to the power grid; then the AC is converted into smooth DC through the first rectifier unit, and provided to the control unit and the PWM unit respectively, to provide working voltage for the overall power supply circuit. The control unit outputs the timing electrical signal to the PWM unit, and the PWM unit controls the conduction or cutoff of the high and low voltage MOS tubes through the duty cycle voltage; the PWM unit is connected to the transformer unit, and adopts the LLC half-bridge resonant control circuit to provide a 50% complementary duty cycle for the transformer unit, so that the power supply efficiency is greatly improved; further, the turns ratio of the primary coil and the secondary coil at the input end of the transformer T1 is accurately calculated and designed, and the combination of electromagnetic induction + PWM switch control signal is used to output a "sinusoidal" DC voltage in a positive and negative 180-degree conduction / shutdown mode through the high and low voltage MOS tubes, and transmit it to the second rectifier unit; the second rectifier unit performs a secondary "AC-DC" conversion on the 180-degree phase DC power into a unidirectional smooth DC power, and then obtains a high-rate DC voltage output through capacitor coupling; then the feedback unit takes the output voltage of the secondary rectifier filter circuit, collects and amplifies the voltage signal through the optocoupler transmitter U1, and feeds it back to the control unit for comparison with the reference voltage, so that the control unit adjusts the output timing signal to the PWM unit, thereby controlling the stability of the output terminal CN1.

[0054] The scheme of the present application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of the various embodiments have their own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. Those skilled in the art should also be aware that the actions and modules involved in the specification are not necessarily required for the present application. In addition, it can be understood that the steps in the method of the embodiment of the present application can be adjusted in order, merged and deleted according to actual needs, and the modules in the device of the embodiment of the present application can be merged, divided and deleted according to actual needs.

[0055] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A LED high-rate switching power supply driving circuit, characterized in that: include: Main control module; An input module, the input module comprising a noise reduction unit and a first rectifying unit, the noise reduction unit is electrically connected to the first rectifying unit, and the first rectifying unit is electrically connected to the main control module; An output module is electrically connected to the main control module.

2. The LED high-rate switching power supply driving circuit according to claim 1, characterized in that: The input module includes an interface CN2 and a fuse F1 , and the fuse F1 is electrically connected to the interface CN2 .

3. The LED high-rate switching power supply driving circuit according to claim 2, characterized in that: The noise reduction unit includes a thermistor NTC1, a varistor TVR1, a capacitor CX1, a common mode inductor L1, a capacitor CY2 and a capacitor CY3. The first end of the varistor TVR1 is electrically connected to the fuse F1, the second end of the varistor TVR1 is electrically connected to the first end of the thermistor NTC1, the first end of the thermistor NTC1 is also electrically connected to the interface CN2, the second end of the thermistor NTC1 is electrically connected to the first end of the capacitor CX1, the second end of the capacitor CX1 is electrically connected to the common mode inductor L1, the first end of the capacitor CY2 is electrically connected to the common mode inductor L1, the second end of the capacitor CY2 is electrically connected to the first end of the capacitor CY3, and the second end of the capacitor CY3 is grounded.

4. The LED high-rate switching power supply driving circuit according to claim 3, characterized in that: The first rectifying unit includes a rectifying bridge tube DB1 and a rectifying bridge tube DB2 , and the rectifying bridge tube DB1 and the rectifying bridge tube DB2 are electrically connected to the common mode inductor L1 , respectively.

5. The LED high-rate switching power supply driving circuit according to claim 4, characterized in that: The first rectifier unit also includes a capacitor C15, a capacitor C16 and a capacitor CY1, the first end of the capacitor C15 is electrically connected to the first end of the capacitor C16, the second end of the capacitor C15 is electrically connected to the second end of the capacitor C16, the first end of the capacitor C16 is electrically connected to the rectifier bridge tube DB1, the second end of the capacitor C16 is electrically connected to the rectifier bridge tube DB2, and the first end of the capacitor CY1 is electrically connected to the first end of the capacitor C15.

6. The LED high-rate switching power supply driving circuit according to claim 4, characterized in that: The main control module includes a control unit, which includes a chip U3, a resistor R30 and a resistor R31. The first end of the resistor R30 is electrically connected to the rectifier bridge tube DB2, the second end of the resistor R30 is electrically connected to the first end of the resistor R31, and the second end of the resistor R31 is electrically connected to the chip U3.

7. The LED high-rate switching power supply driving circuit according to claim 6, characterized in that: The control unit also includes a resistor R24, a resistor R28, a resistor R15 and a capacitor C12, the first end of the resistor R24 ​​is electrically connected to the rectifier bridge tube DB2, the second end of the resistor R24 ​​is electrically connected to the first end of the resistor R28, the second end of the resistor R28 is electrically connected to the first end of the capacitor C12, the second end of the capacitor C12 is electrically connected to the first end of the resistor R15, and the second end of the resistor R15 is electrically connected to the chip U3.

8. The LED high-rate switching power supply driving circuit according to claim 6, characterized in that: The control unit further includes a capacitor C13, a first end of the capacitor C13 is electrically connected to the chip U3, and a second end of the capacitor C13 is grounded.

9. The LED high-rate switching power supply driving circuit according to claim 6, characterized in that: The control unit further includes a resistor R20 and a resistor R19, a first end of the resistor R20 is electrically connected to the chip U3, a second end of the resistor R20 is electrically connected to a first end of the resistor R19, and a second end of the resistor R19 is grounded.

10. The LED high-rate switching power supply driving circuit according to claim 9, characterized in that: The control unit also includes a capacitor C17 and a resistor R23, wherein a first end of the capacitor C17 is electrically connected to a first end of the resistor R23, and a first end of the resistor R23 is also electrically connected to the chip U3, a second end of the capacitor C17 is grounded, and a second end of the resistor R23 is electrically connected to a first end of the resistor R19.

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