Constant power circuit of color temperature adjustable lamp

Abstract

The utility model discloses a constant power circuit of a color temperature adjustable lamp. The constant power circuit comprises a constant current drive circuit, a control circuit, a switch circuit and a light source circuit. According to the utility model, the switching of color temperature is realized by controlling the on-off of the MOS tube Q1 and the MOS tube Q2 through the switch member SW1, switching signals of the optocoupler module OP1 and the optocoupler module OP2 are provided through the switch member SW1, so that the pin 4 and the pin 5 of the control chip U3 collect corresponding color temperature signals, and then the control chip U3 outputs a corresponding PWM dimming signal AD1 to the driving module U1 according to the setting of an internal program. And the driving module U1 outputs corresponding current according to the received PWM dimming signal AD1, so that the corresponding current is output under different color temperatures, and the constant power of the different color temperatures is realized.

Description

Technical Field

[0001] The utility model belongs to the technical field of constant power circuits of color temperature adjustable lamps, and in particular relates to a constant power circuit of color temperature adjustable lamps. Background Art

[0002] As LED light source technology continues to mature, in order to reduce the supplier's product inventory integration and the variability of customer color temperature selection, the demand for color temperature adjustment of lighting products has become imminent. Indoor lamps, light sources and outdoor lamps all have the need to adjust color temperature. However, since the LED driver adopts a constant current solution, the change in color temperature will cause the LED voltage to change, so that the power of the whole lamp cannot be kept consistent. Therefore, general color-adjusting lighting products cannot achieve constant power.

[0003] It is found in the use of existing color-adjusting lighting products that the power of the middle color temperature is lower than that of the other two levels. For products exported to Europe, due to the requirements of ERP, the low power of the middle color temperature will cause the whole lamp to fail to meet the power specified by ERP at different color temperatures. Therefore, there is an urgent need for a constant power circuit for adjustable color temperature lamps to achieve constant power at different color temperatures. Utility Model Content

[0004] The purpose of the utility model is to provide a constant power circuit of a color temperature adjustable lamp to solve the problems raised in the above background technology. The utility model provides a constant power circuit of a color temperature adjustable lamp, which has the characteristic of being able to achieve constant power at different color temperatures.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a constant power circuit of an adjustable color temperature lamp, comprising a constant current drive circuit, a control circuit, a switch circuit and a light source circuit, wherein the constant current drive circuit comprises a drive module U1 with PWM dimming and a 12V auxiliary power supply for powering the control circuit and the light source circuit; the control circuit comprises a control chip U3 for receiving a color temperature signal and outputting a PWM dimming signal AD1, and an optical coupler module OP1 and an optical coupler module OP2 for driving the output isolated from the auxiliary power supply; the light source circuit comprises a low color temperature LED1 and a high color temperature LED2; the switch circuit comprises a MOS tube Q2 for controlling the on and off of the low color temperature LED1, a MOS tube Q1 for controlling the on and off of the high color temperature LED2, and a switch element SW1 for controlling the MOS tube Q1 and the MOS tube Q2.

[0006] Further in the utility model, the constant current drive circuit also includes a signal amplifier Q3, wherein the B pin of the signal amplifier Q3 is connected to the 3 pin of the control chip U3, the C pin of the signal amplifier Q3 is connected to one end of the resistor R11, the other end of the resistor R11 is connected to the 5 pin of the drive module U1, and the E pin of the signal amplifier Q3 is connected to the 6 pin of the drive module U1.

[0007] Further in the utility model, the control circuit also includes a linear power supply chip U2, wherein pin 1 of the linear power supply chip U2 is connected to pin 7 of the driving module U1, pin 3 of the linear power supply chip U2 is connected to pin 6 of the driving module U1, pin 2 of the linear power supply chip U2 is connected to pin 1 of the control chip U3, and pin 4 of the linear power supply chip U2 is connected to pin 2 of the control chip U3.

[0008] In the present invention, a resistor R9 is further connected between pin 4 of the control chip U3 and pin 1 of the control chip U3 , and a resistor R10 is connected between pin 5 of the control chip U3 and pin 1 of the control chip U3 .

[0009] Further in the utility model, pin 1 of the optocoupler module OP1 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to pin 4 of the control chip U3, pin 2 of the optocoupler module OP1 is connected to the resistor R6, the other end of the resistor R6 is connected to pin 3 of the switch element SW1, pin 1 of the optocoupler module OP2 is connected to the resistor R7, the other end of the resistor R7 is connected to pin 5 of the control chip U3, pin 2 of the optocoupler module OP2 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to pin 1 of the switch element SW1, pin 4 of the optocoupler module OP1 and pin 4 of the optocoupler module OP2 are both connected to pin 2 of the control chip U3, and pin 3 of the optocoupler module OP1 and pin 3 of the optocoupler module OP2 are both connected to pin 4 of the drive module U1.

[0010] Further in the utility model, the cathode terminal of the low color temperature LED1 is connected to the D pole of the MOS tube Q2, the G pole of the MOS tube Q2 is connected to the 3rd pin of the switch element SW1, the cathode terminal of the high color temperature LED2 is connected to the D pole of the MOS tube Q1, the G pole of the MOS tube Q1 is connected to the 1st pin of the switch element SW1, and the S pole of the MOS tube Q1, the S pole of the MOS tube Q2 and the 2nd pin of the switch element SW1 are all connected to the 4th pin of the driving module U1.

[0011] Further in the utility model, the G pole of the MOS tube Q2 is also connected to the resistor R1, the resistor R3, the Zener diode D1 and one end of the capacitor C1 respectively, the G pole of the MOS tube Q1 is also connected to the resistor R2, the resistor R4, the Zener diode D2 and one end of the capacitor C2 respectively, the other ends of the resistor R1 and the resistor R2 are respectively connected to the 3rd pin of the driving module U1, and the other ends of the resistor R3, the Zener diode D1, the capacitor C1, the resistor R4, the Zener diode D2 and the capacitor C2 are respectively connected to the 4th pin of the driving module U1.

[0012] In the present invention, the method for realizing a constant power circuit of a color temperature adjustable lamp further comprises the following steps:

[0013] (i) When the switch SW1 is turned to pin 1, pins 1 and 2 of the switch SW1 are connected. At this time, MOS tube Q1 is not conducting, MOS tube Q2 is conducting, and low color temperature LED 1 is lit; the optocoupler module OP1 is conducting, pin 1 of the optocoupler module OP1 is a low-level signal, the optocoupler module OP2 is not conducting, and pin 1 of the optocoupler module OP2 is a high-level signal; after pins 4 and 5 of the control chip U3 collect the signal, the corresponding PWM dimming signal AD1 is output through pin 3 to pin 5 of the driving module U1, and the control chip U3 controls the output current of pin 3 according to the received PWM dimming signal AD1;

[0014] (ii) When the switch SW1 is turned to the empty position, the MOS tube Q1 is turned on, the MOS tube Q2 is turned on, and the low color temperature LED1 and the high color temperature LED2 are both lit; the optocoupler module OP1 is turned on, and the pin 1 of the optocoupler module OP1 is a low level signal; the optocoupler module OP2 is turned on, and the pin 1 of the optocoupler module OP2 is a low level signal; after the 4th and 5th pins of the control chip U3 collect the signal, the corresponding PWM dimming signal AD1 is output through the 3rd pin to the 5th pin of the driving module U1, and the control chip U3 controls the output current of the 3rd pin according to the received PWM dimming signal AD1;

[0015] (III) When the switch SW1 is moved to pin 3, pin 3 and pin 2 of the switch SW1 are connected. At this time, MOS tube Q1 is turned on, MOS tube Q2 is not turned on, and the high color temperature LED 2 is lit; the optocoupler module OP1 is not turned on, and pin 1 of the optocoupler module OP1 is a high-level signal; the optocoupler module OP2 is turned on, and pin 1 of the optocoupler module OP2 is a low-level signal; after pins 4 and 5 of the control chip U3 collect the signal, the corresponding PWM dimming signal AD1 is output through pin 3 to pin 5 of the driving module U1, and the control chip U3 controls the output current of pin 3 according to the received PWM dimming signal AD1.

[0016] Compared with the prior art, the beneficial effects of the utility model are:

[0017] 1. The utility model realizes the switching of color temperature by controlling the on and off of MOS tube Q1 and MOS tube Q2 through the switch element SW1. At the same time, the switch element SW1 provides the switching signal of the optical coupling module OP1 and the optical coupling module OP2, so that the 4th and 5th pins of the control chip U3 collect the corresponding color temperature signal. Then the control chip U3 outputs the corresponding PWM dimming signal AD1 to the driving module U1 according to the setting of the internal program. The driving module U1 outputs the corresponding current according to the received PWM dimming signal AD1, and realizes the output of the corresponding current under different color temperatures, thereby realizing the constant power of different color temperatures;

[0018] 2. The utility model realizes the line isolation of the drive output and the auxiliary power supply through the setting of the optical coupling module OP1 and the optical coupling module OP2;

[0019] 3. The utility model can achieve versatility with different drives, different powers and different color temperatures;

[0020] 4. The utility model adopts a single chip microcomputer to control the ratio of the dimming signal, which can achieve high-precision dimming requirements;

[0021] 5. The utility model adopts electronic switch MOS tube Q1 and MOS tube Q2, which can make the dip switch meet the color temperature adjustment of high voltage and large current. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a circuit connection block diagram of the utility model;

[0023] Figure 2 This is a circuit diagram of the constant current drive circuit of the utility model;

[0024] Figure 3 A circuit diagram showing the connection between the control circuit, the switch circuit and the light source circuit of the utility model;

[0025] Figure 4 It is a circuit diagram of the control circuit of the utility model;

[0026] Figure 5 A circuit diagram showing the connection between the switch circuit and the light source circuit of the utility model;

[0027] In the figure: 1. constant current drive circuit; 2. control circuit; 3. switch circuit; 4. light source circuit. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] Example 1

[0030] See also Figure 1-5The utility model provides the following technical solutions: a constant power circuit of an adjustable color temperature lamp, comprising a constant current drive circuit 1, a control circuit 2, a switch circuit 3 and a light source circuit 4, wherein the constant current drive circuit 1 comprises a drive module U1 with PWM dimming and a 12V auxiliary power supply for powering the control circuit 2 and the light source circuit 4; the control circuit 2 comprises a control chip U3 for receiving a color temperature signal and outputting a PWM dimming signal AD1, and an optical coupler module OP1 and an optical coupler module OP2 for driving the output and isolating the auxiliary power supply, and pins 4 and 5 of the control chip U3 are color temperature signal collection pins; the light source circuit 4 comprises a low color temperature LED 1 and a high color temperature LED 2; the switch circuit comprises a MOS tube Q2 for controlling the on and off of the low color temperature LED 1, a MOS tube Q1 for controlling the on and off of the high color temperature LED 2, and a switch element SW1 for controlling the MOS tube Q1 and the MOS tube Q2, and the switch element SW1 is a three-speed dial switch.

[0031] By adopting the above technical solution, the utility model controls the on and off of the MOS tube Q1 and the MOS tube Q2 through the switch element SW1 to achieve the switching of the color temperature. At the same time, the switch element SW1 also provides the switching signals of the optical coupling module OP1 and the optical coupling module OP2, so that the 4th and 5th pins of the control chip U3 collect the corresponding color temperature signals, and then the control chip U3 outputs the corresponding PWM dimming signal AD1 to the driving module U1 according to the setting of the internal program. The driving module U1 outputs the corresponding current according to the received PWM dimming signal AD1, and realizes the output of the corresponding current under different color temperatures, thereby realizing the constant power of different color temperatures; the utility model adopts the electronic switch MOS tube Q1 and the MOS tube Q2, so that the dip switch can meet the color temperature adjustment of high voltage and large current.

[0032] Specifically, the constant current driving circuit 1 also includes a signal amplifier Q3, wherein the B pin of the signal amplifier Q3 is connected to the 3 pin of the control chip U3, the C pin of the signal amplifier Q3 is connected to one end of the resistor R11, the other end of the resistor R11 is connected to the 5 pin of the driving module U1, and the E pin of the signal amplifier Q3 is connected to the 6 pin of the driving module U1.

[0033] By adopting the above technical solution, the 5V PWM signal of the control chip U3 is converted into a 12V PWM signal.

[0034] Specifically, the control circuit 2 also includes a linear power supply chip U2, wherein pin 1 of the linear power supply chip U2 is connected to pin 7 of the driving module U1, pin 3 of the linear power supply chip U2 is connected to pin 6 of the driving module U1, pin 2 of the linear power supply chip U2 is connected to pin 1 of the control chip U3, and pin 4 of the linear power supply chip U2 is connected to pin 2 of the control chip U3.

[0035] By adopting the above technical solution, the 12V power supply is converted into a 5V power supply to power the control chip U3.

[0036] Specifically, a resistor R9 is connected between pin 4 of the control chip U3 and pin 1 of the control chip U3 , and a resistor R10 is connected between pin 5 of the control chip U3 and pin 1 of the control chip U3 .

[0037] By adopting the above technical solution, as a pull-up resistor, a pull-up level signal is provided for pins 4 and 5 of the control chip U3.

[0038] Specifically, pin 1 of the optocoupler module OP1 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to pin 4 of the control chip U3, pin 2 of the optocoupler module OP1 is connected to the resistor R6, the other end of the resistor R6 is connected to pin 3 of the switch element SW1, pin 1 of the optocoupler module OP2 is connected to the resistor R7, the other end of the resistor R7 is connected to pin 5 of the control chip U3, pin 2 of the optocoupler module OP2 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to pin 1 of the switch element SW1, pin 4 of the optocoupler module OP1 and pin 4 of the optocoupler module OP2 are both connected to pin 2 of the control chip U3, and pin 3 of the optocoupler module OP1 and pin 3 of the optocoupler module OP2 are both connected to pin 4 of the drive module U1.

[0039] By adopting the above technical solution, line isolation between the drive output and the auxiliary power supply is achieved through the optical coupling module OP1 and the optical coupling module OP2.

[0040] Specifically, the cathode terminal of the low color temperature LED1 is connected to the D pole of the MOS tube Q2, the G pole of the MOS tube Q2 is connected to the 3rd pin of the switch element SW1, the cathode terminal of the high color temperature LED2 is connected to the D pole of the MOS tube Q1, the G pole of the MOS tube Q1 is connected to the 1st pin of the switch element SW1, and the S pole of the MOS tube Q1, the S pole of the MOS tube Q2 and the 2nd pin of the switch element SW1 are all connected to the 4th pin of the driving module U1.

[0041] By adopting the above technical solution, the switching of the color temperature is achieved by controlling the on and off of the MOS transistor Q1 and the MOS transistor Q2 through the switch element SW1.

[0042] Example 2

[0043] The difference between this embodiment and Embodiment 1 is that: specifically, the G pole of the MOS tube Q2 is also connected to the resistor R1, the resistor R3, the voltage-stabilizing diode D1 and one end of the capacitor C1 respectively, the other end of the resistor R1 is connected to the 3rd pin of the driving module U1, and the other ends of the resistor R3, the voltage-stabilizing diode D1 and the capacitor C1 are respectively connected to the 4th pin of the driving module U1.

[0044] By adopting the above technical solution, after the voltage between the 3rd and 4th pins of the driving module U1 is divided by the resistors R1 and R3, a power supply signal close to the MOS tube Q2 is generated at both ends of the resistor R3. The capacitor C1 is a filter capacitor, and the diode D1 is a voltage regulator diode, which clamps the voltage of the resistor R3 within the operating voltage range of the MOS tube Q2.

[0045] Specifically, the G pole of the MOS tube Q1 is also connected to the resistor R2, the resistor R4, the voltage-stabilizing diode D2 and one end of the capacitor C2 respectively, the other end of the resistor R2 is connected to the 3rd pin of the driving module U1, and the other ends of the resistor R4, the voltage-stabilizing diode D2 and the capacitor C2 are respectively connected to the 4th pin of the driving module U1.

[0046] By adopting the above technical solution, the voltage between the 3rd and 4th pins of the driving module U1 is divided by the resistors R2 and R4, and a power supply signal close to the MOS tube Q1 is generated at both ends of the resistor R4. The capacitor C2 is a filter capacitor, and the diode D2 is a voltage regulator diode, which clamps the voltage of the resistor R4 within the operating voltage range of the MOS tube Q1.

[0047] Example 3

[0048] Furthermore, the method for realizing a constant power circuit of a color temperature adjustable lamp described in the utility model comprises the following steps:

[0049] (i) When the switch SW1 is turned to pin 1, pins 1 and 2 of the switch SW1 are connected. At this time, MOS tube Q1 is not conducting, MOS tube Q2 is conducting, and low color temperature LED 1 is lit; the optocoupler module OP1 is conducting, pin 1 of the optocoupler module OP1 is a low-level signal, the optocoupler module OP2 is not conducting, and pin 1 of the optocoupler module OP2 is a high-level signal; after pins 4 and 5 of the control chip U3 collect the signal, the corresponding PWM dimming signal AD1 is output through pin 3 to pin 5 of the driving module U1, and the control chip U3 controls the output current of pin 3 according to the received PWM dimming signal AD1;

[0050] (ii) When the switch SW1 is turned to the empty position, the MOS tube Q1 is turned on, the MOS tube Q2 is turned on, and the low color temperature LED1 and the high color temperature LED2 are both lit; the optocoupler module OP1 is turned on, and the pin 1 of the optocoupler module OP1 is a low level signal; the optocoupler module OP2 is turned on, and the pin 1 of the optocoupler module OP2 is a low level signal; after the 4th and 5th pins of the control chip U3 collect the signal, the corresponding PWM dimming signal AD1 is output through the 3rd pin to the 5th pin of the driving module U1, and the control chip U3 controls the output current of the 3rd pin according to the received PWM dimming signal AD1;

[0051] (III) When the switch SW1 is moved to pin 3, pin 3 and pin 2 of the switch SW1 are connected. At this time, MOS tube Q1 is turned on, MOS tube Q2 is not turned on, and the high color temperature LED 2 is lit; the optocoupler module OP1 is not turned on, and pin 1 of the optocoupler module OP1 is a high-level signal; the optocoupler module OP2 is turned on, and pin 1 of the optocoupler module OP2 is a low-level signal; after pins 4 and 5 of the control chip U3 collect the signal, the corresponding PWM dimming signal AD1 is output through pin 3 to pin 5 of the driving module U1, and the control chip U3 controls the output current of pin 3 according to the received PWM dimming signal AD1.

[0052] In the utility model, the driving module U1 adopts the SS-100NL-E260BH type of Songsheng; the signal amplifier Q3 adopts the MMBT3904LT type; the linear power supply chip U2 adopts the LM7805 type three-terminal voltage regulator; the control chip U3 adopts the AS7130 type single-chip microcomputer; the optical coupling module OP1 and the optical coupling module OP2 both adopt the EL817C type.

[0053] In summary, the utility model controls the on and off of the MOS tube Q1 and the MOS tube Q2 through the switch element SW1 to achieve the switching of the color temperature, and also provides the switching signals of the optical coupling module OP1 and the optical coupling module OP2 through the switch element SW1, so that the 4th and 5th pins of the control chip U3 collect the corresponding color temperature signals, and then the control chip U3 outputs the corresponding PWM dimming signal AD1 to the driving module U1 according to the setting of the internal program, and the driving module U1 outputs the corresponding current according to the received PWM dimming signal AD1, so as to output the corresponding current under different color temperatures, thereby achieving constant power of different color temperatures; the utility model realizes the line isolation of the driving output and the auxiliary power supply through the setting of the optical coupling module OP1 and the optical coupling module OP2; the utility model can realize the versatility of different drives, different powers and different color temperatures; the utility model adopts a single chip microcomputer to control the ratio of the dimming signal, so as to achieve high-precision dimming requirements.

[0054] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A constant power circuit for a color temperature adjustable lamp, characterized in that: It includes a constant current drive circuit, a control circuit, a switch circuit and a light source circuit, wherein: The constant current driving circuit includes a driving module U1 with PWM dimming and 12V auxiliary power supply for powering the control circuit and the light source circuit; The control circuit includes a control chip U3 for receiving a color temperature signal and outputting a PWM dimming signal AD1, and an optical coupling module OP1 and an optical coupling module OP2 for driving the output to be isolated from an auxiliary power supply; The light source circuit includes a low color temperature LED 1 and a high color temperature LED 2; The switch circuit includes a MOS transistor Q2 for controlling the on and off of the low color temperature LED 1 , a MOS transistor Q1 for controlling the on and off of the high color temperature LED 2 , and a switch element SW1 for controlling the MOS transistor Q1 and the MOS transistor Q2 .

2. The constant power circuit of a color temperature adjustable lamp according to claim 1, characterized in that: The constant current driving circuit also includes a signal amplifier Q3, wherein the B pin of the signal amplifier Q3 is connected to the 3 pin of the control chip U3, the C pin of the signal amplifier Q3 is connected to one end of the resistor R11, the other end of the resistor R11 is connected to the 5 pin of the driving module U1, and the E pin of the signal amplifier Q3 is connected to the 6 pin of the driving module U1.

3. The constant power circuit of a color temperature adjustable lamp according to claim 1, characterized in that: The control circuit also includes a linear power supply chip U2, wherein pin 1 of the linear power supply chip U2 is connected to pin 7 of the driving module U1, pin 3 of the linear power supply chip U2 is connected to pin 6 of the driving module U1, pin 2 of the linear power supply chip U2 is connected to pin 1 of the control chip U3, and pin 4 of the linear power supply chip U2 is connected to pin 2 of the control chip U3.

4. The constant power circuit of a color temperature adjustable lamp according to claim 1, characterized in that: A resistor R9 is connected between the pin 4 of the control chip U3 and the pin 1 of the control chip U3 , and a resistor R10 is connected between the pin 5 of the control chip U3 and the pin 1 of the control chip U3 .

5. The constant power circuit of a color temperature adjustable lamp according to claim 1, characterized in that: Pin 1 of the optocoupler module OP1 is connected to one end of the resistor R8, the other end of the resistor R8 is connected to pin 4 of the control chip U3, pin 2 of the optocoupler module OP1 is connected to the resistor R6, the other end of the resistor R6 is connected to pin 3 of the switch element SW1, pin 1 of the optocoupler module OP2 is connected to the resistor R7, the other end of the resistor R7 is connected to pin 5 of the control chip U3, pin 2 of the optocoupler module OP2 is connected to one end of the resistor R5, the other end of the resistor R5 is connected to pin 1 of the switch element SW1, pin 4 of the optocoupler module OP1 and pin 4 of the optocoupler module OP2 are both connected to pin 2 of the control chip U3, and pin 3 of the optocoupler module OP1 and pin 3 of the optocoupler module OP2 are both connected to pin 4 of the drive module U1.

6. The constant power circuit of a color temperature adjustable lamp according to claim 1, characterized in that: The cathode terminal of the low color temperature LED1 is connected to the D pole of the MOS tube Q2, the G pole of the MOS tube Q2 is connected to the 3rd pin of the switch element SW1, the cathode terminal of the high color temperature LED2 is connected to the D pole of the MOS tube Q1, the G pole of the MOS tube Q1 is connected to the 1st pin of the switch element SW1, and the S pole of the MOS tube Q1, the S pole of the MOS tube Q2 and the 2nd pin of the switch element SW1 are all connected to the 4th pin of the driving module U1.

7. The constant power circuit of a color temperature adjustable lamp according to claim 6, characterized in that: The G pole of the MOS tube Q2 is also connected to the resistor R1, the resistor R3, the zener diode D1 and one end of the capacitor C1 respectively, the G pole of the MOS tube Q1 is also connected to the resistor R2, the resistor R4, the zener diode D2 and one end of the capacitor C2 respectively, the other ends of the resistor R1 and the resistor R2 are respectively connected to the 3rd pin of the driving module U1, and the other ends of the resistor R3, the zener diode D1, the capacitor C1, the resistor R4, the zener diode D2 and the capacitor C2 are respectively connected to the 4th pin of the driving module U1.

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