Dial-up dimming circuit, PCB and small power supply

Abstract

The utility model discloses a dial dimming circuit, a PCB and a small power supply. The circuit comprises an input processing unit, a constant voltage driving unit, an illumination driving unit, a dial unit and an output unit. The input end of the input processing unit is used for being connected with an external power supply device, and the output end of the input processing unit is connected with the constant-voltage driving unit, the illumination driving unit and the output unit. The drain end of the illumination driving unit is respectively connected with the drain end of the constant voltage driving unit and the input end of the output unit, the dial-up unit is respectively connected with the sampling end of the illumination driving unit and the output unit, and the output end of the output unit is used for being connected with an illumination device; the circuit disclosed by the utility model is provided with the dial-up unit, and a user can flexibly adjust the lighting effect of the lighting lamp according to an actual application scene, so that the use experience is improved; the whole circuit is simple in design, a peripheral circuit is simple, the total size of a circuit board is effectively reduced, the size of the driving power supply is further reduced, and the requirements of miniaturized lighting equipment are met.

Description

Technical Field

[0001] This utility model relates to the field of dimming circuit technology, and in particular to a DIP switch dimming circuit, a PCB board, and a small power supply. Background Technology

[0002] In today's modern lighting technology field, dimmable power supplies play a crucial role. In many lighting circuit applications, when users want to apply different power current levels to the load luminaires, they usually manually adjust the DIP switches to ensure that they can switch to the correct level, thereby achieving precise control of the load's output current. However, the DIP switch dimming circuit designs currently on the market are often accompanied by complex peripheral circuits, which not only increases the size of the circuit board but also makes the overall size of the driver power supply larger. This size limitation makes it difficult for these driver power supplies to adapt to modern lighting products with strict requirements for miniaturization. Therefore, existing dimmable power supplies are inadequate in meeting the market's growing demand for miniaturized and high-efficiency lighting equipment.

[0003] It is evident that existing technologies still need improvement and enhancement. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a DIP switch dimming circuit with a simple overall circuit design and simple peripheral circuit, which effectively reduces the overall size of the circuit board and thus reduces the size of the driving power supply.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A DIP switch dimming circuit includes an input processing unit, a constant voltage driving unit, an illumination driving unit, a DIP switch unit, and an output unit. The input terminal of the input processing unit is used to connect to an external power supply device, and the output terminal of the input processing unit is connected to the constant voltage driving unit, the illumination driving unit, and the output unit, respectively. The drain terminal of the constant voltage driving unit is connected to the drain terminal of the illumination driving unit, and the drain terminal of the illumination driving unit is also connected to the input terminal of the output unit. The DIP switch unit is connected to the sampling terminal of the illumination driving unit and the output unit, respectively, and the output terminal of the output unit is used to connect to an illumination device.

[0007] In the aforementioned DIP switch dimming circuit, the input processing unit includes a first connector CN1, a first filter section, a rectifier section, and a second filter section. The first connector CN1 is used to connect to an external power supply device. The first connector CN1 is also connected to the input terminal of the first filter section. The output terminal of the first filter section is connected to the input terminal of the rectifier section. The output terminal of the rectifier section is connected to the power supply terminals of the constant voltage drive unit, the lighting drive unit, and the input terminal of the second filter section, respectively. The output terminal of the second filter section is connected to the output unit.

[0008] In the aforementioned DIP switch dimming circuit, the constant voltage drive unit includes a step-down section, a leakage protection section, and a first control chip U1; the input terminal of the step-down section is connected to the output terminal of the rectifier section, and the output terminal of the step-down section is connected to the VCC pin of the first control chip U1; the pin D of the first control chip U1 is connected to the leakage terminal of the lighting drive unit through the leakage protection section.

[0009] In the aforementioned DIP switch dimming circuit, the constant voltage drive unit further includes a feedback section and a first sampling section; the input terminal of the feedback section is connected to the output terminal of the leakage protection section, and the output terminal of the feedback section is connected to the pin FB of the first control chip U1; one end of the sampling section is connected to the pin CS of the first control chip U1, and the other end of the sampling section is grounded.

[0010] In the aforementioned DIP switch dimming circuit, the lighting driving unit includes a second control chip U2, a first voltage divider, and a second voltage divider; the input terminal of the first voltage divider is connected to the output terminal of the second filter, and the output terminal of the first voltage divider is connected to pin ZCD of the second control chip U2; the output terminal of the rectifier is connected to pin VCC of the second control chip U2 through the second voltage divider; and pin DRAIN of the second control chip U2 is connected to the output terminal of the leakage protection unit and the input terminal of the output unit, respectively.

[0011] In the aforementioned DIP switch dimming circuit, the lighting driving unit further includes a second sampling section and an amplification output section; one end of the amplification output section is connected to the COMP pin of the second control chip U2, and the other end of the amplification output section is grounded; one end of the second sampling section is connected to the CS pin of the second control chip U2, and the other end of the second sampling section is connected to the DIP switch unit.

[0012] In the aforementioned DIP switch dimming circuit, the output unit includes a third voltage divider, a third filter, and a second connector CN2; the input terminal of the third voltage divider is connected to the DRAIN pin of the second control chip U2, and the output terminal of the third voltage divider is connected to the input terminal of the third filter; the output terminal of the second filter is connected to the input terminal of the third filter, and the output terminal of the third filter is connected to the second connector CN2, which is used to connect a lighting fixture; the DIP switch unit is connected to the third voltage divider.

[0013] In the aforementioned DIP switch dimming circuit, the DIP switch unit includes a first DIP switch section and a second DIP switch section. One end of the first DIP switch section and one end of the second DIP switch section are respectively connected to the other end of the second sampling section, and the other ends of the first DIP switch section and the other ends of the second DIP switch section are respectively connected to the third voltage divider section.

[0014] This utility model also provides a PCB board, on which the DIP switch dimming circuit described above is printed.

[0015] This utility model also provides a small power supply, which uses the DIP switch dimming circuit described above to achieve working control.

[0016] Beneficial effects:

[0017] This invention provides a DIP switch dimming circuit. By configuring a DIP switch unit, users can flexibly adjust the lighting effect of the lighting fixture according to the actual application scenario, thereby improving the user experience. By configuring a constant voltage drive unit and a lighting drive unit, it can ensure that the lighting device maintains a stable brightness output even when the external power supply voltage fluctuates, avoiding the phenomenon of flickering brightness, thereby improving the working stability of the lighting device and extending its service life. The entire circuit design is simple, the peripheral circuit is simple, effectively reducing the overall size of the circuit board, and thus reducing the size of the drive power supply to meet the needs of miniaturized lighting equipment. Attached Figure Description

[0018] Figure 1 A circuit block diagram of the DIP switch dimming circuit provided by this utility model;

[0019] Figure 2 The circuit diagram of the DIP switch dimming circuit provided by this utility model;

[0020] Figure 3 A schematic diagram of the structure of the small power supply provided by this utility model.

[0021] Explanation of main component symbols: 1-Input processing unit, 11-First filter section, 12-Rectifier section, 13-Second filter section, 2-Constant voltage drive unit, 21-Voltage step-down section, 22-Leakage protection section, 23-Feedback section, 24-First sampling section, 3-Lighting drive unit, 31-First voltage divider section, 32-Second voltage divider section, 33-Second sampling section, 34-Amplification output section, 4-DIP switch unit, 41-First DIP switch section, 42-Second DIP switch section, 5-Output unit, 51-Third voltage divider section, 52-Third filter section. Detailed Implementation

[0022] This utility model provides a DIP switch dimming circuit, a PCB board, and a small power supply. To make the purpose, technical solution, and effects of this utility model clearer and more explicit, the following describes this utility model in further detail with reference to the accompanying drawings and embodiments.

[0023] In the description of this utility model, it should be understood that the terms "installation" and "connection" should be interpreted broadly, and those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0024] Please see Figure 1 and Figure 2 This utility model provides a DIP switch dimming circuit, including an input processing unit 1, a constant voltage driving unit 2, an illumination driving unit 3, a DIP switch unit 4, and an output unit 5. The input terminal of the input processing unit 1 is used to connect to an external power supply device, and the output terminal of the input processing unit 1 is connected to the constant voltage driving unit 2, the illumination driving unit 3, and the output unit 5, respectively. The drain terminal of the constant voltage driving unit 2 is connected to the drain terminal of the illumination driving unit 3, and the drain terminal of the illumination driving unit 3 is also connected to the input terminal of the output unit 5. The DIP switch unit 4 is connected to the sampling terminal of the illumination driving unit 3 and the output unit 5, respectively, and the output terminal of the output unit 5 is used to connect to an illumination device.

[0025] The DIP switch dimming circuit disclosed in this application allows users to flexibly adjust the lighting effect of the lighting fixture according to the actual application scenario by configuring the DIP switch unit 4, thereby improving the user experience. By configuring the constant voltage drive unit 2 and the lighting drive unit 3, it can ensure that the lighting device maintains a stable brightness output even when the external power supply voltage fluctuates, avoiding the phenomenon of the lighting device flickering, thereby improving the working stability of the lighting device and extending its service life. The entire circuit design is simple, the peripheral circuit is simple, and the overall size of the circuit board is effectively reduced, thereby reducing the size of the drive power supply to meet the needs of miniaturized lighting equipment.

[0026] Further, please refer to Figure 1 and Figure 2The input processing unit 1 includes a first connector CN1, a first filter section 11, a rectifier section 12, and a second filter section 13. The first connector CN1 is used to connect to an external power supply device. The first connector CN1 is also connected to the input terminal of the first filter section 11. The output terminal of the first filter section 11 is connected to the input terminal of the rectifier section 12. The output terminal of the rectifier section 12 is connected to the power supply terminals of the constant voltage drive unit 2 and the lighting drive unit 3, as well as the input terminal of the second filter section 13. The output terminal of the second filter section 13 is connected to the output unit 5.

[0027] In this embodiment, the external power supply device can be AC ​​mains power. The first filter section 11 includes a first excitation coil LF1, a second excitation coil LF2, and a first inductor L1. The rectifier section 12 includes a rectifier bridge BD1. The second filter section 13 includes a first diode D1 and a second capacitor CY2. One end of the first excitation coil LF1 is connected to pin N and pin L of the first connector CN1, respectively. The other end of the first excitation coil LF1 is connected to one end of the second excitation coil LF2. The other end of the second excitation coil LF2 is connected to one end of the first inductor L1. The other end of the first inductor L1 is connected to the input terminal of the rectifier bridge BD1. The output terminal of the rectifier bridge BD1 is connected to the positive terminal of the first diode D1, the power supply terminal of the constant voltage driving unit 2, and the power supply terminal of the lighting driving unit 3, respectively. The negative terminal of the first diode D1 is connected to one end of the second capacitor CY2, and the other end of the second capacitor CY2 is connected to the output unit 5.

[0028] In this embodiment, the combination of the first filter section 11, the rectifier section 12, and the second filter section 13 ensures the purity and stability of the input power supply through layer-by-layer filtering and rectification. Specifically, the first excitation coil LF1 and the second excitation coil LF2 in the first filter section 11 are connected in series, which not only enhances the filtering effect but also effectively reduces electromagnetic interference, providing a guarantee for the stable operation of subsequent circuits. The introduction of the rectifier bridge BD1 converts AC power to DC power. This conversion process is not only efficient but also stable, providing a high-quality DC power supply for the power supply terminals of the constant voltage drive unit 2 and the lighting drive unit 3. In addition, the combination of the first diode D1 and the second capacitor CY2 further smooths the DC power supply, ensuring the stability and purity of the output current, which is crucial for the performance of the lighting drive unit 3.

[0029] Further, please refer to Figure 1 and Figure 2The constant voltage drive unit 2 includes a step-down section 21, a leakage protection section 22, and a first control chip U1; the input terminal of the step-down section 21 is connected to the output terminal of the rectifier section 12, and the output terminal of the step-down section 21 is connected to the VCC pin of the first control chip U1; the pin D of the first control chip U1 is connected to the leakage terminal of the lighting drive unit 3 through the leakage protection section 22.

[0030] Further, please refer to Figure 1 and Figure 2 The constant voltage drive unit 2 further includes a feedback unit 23 and a first sampling unit 24; the input terminal of the feedback unit 23 is connected to the output terminal of the leakage protection unit 22, and the output terminal of the feedback unit 23 is connected to the pin FB of the first control chip U1; one end of the sampling unit is connected to the pin CS of the first control chip U1, and the other end of the sampling unit is grounded.

[0031] In this embodiment, the first control chip U1 is model BP2636. The step-down section 21 includes a transformer LX, a fourth capacitor C4, and a fourth diode D4. The leakage protection section 22 includes a second diode D2 and a leakage current protector LD1. The feedback section 23 includes a tenth resistor R10 and an eleventh resistor R11. The first sampling section 24 includes a fifth resistor R5, a sixth resistor R6, and a seventh resistor R7. The main coil of the transformer LX is connected to the output terminal of the rectifier bridge BD1. The secondary coil of the transformer LX is inductively connected to the main coil of the transformer. The secondary coil of the transformer LX is connected to the VCC pin of the first control chip U1 through the fourth capacitor C4 and the fourth diode D4 connected in series. The positive terminal of the second diode D2 is connected to the main coil of the transformer LX and pin D of the first control chip U1, respectively. The negative terminal of the second diode D2 is connected to one end of the leakage current protector LD. The other end of the leakage current protector LD is connected to the leakage terminal of the lighting drive unit 3 and one end of the eleventh resistor R11, respectively. The other end of the eleventh resistor R11 is connected to pin FB of the first control chip U1 through the tenth resistor R10. One end of the fifth resistor R5, one end of the sixth resistor R6, and one end of the seventh resistor R7 are connected to pin CS of the first control chip U1, respectively. The other ends of the fifth resistor R5, the sixth resistor R6, and the seventh resistor R7 are grounded.

[0032] In this embodiment, the first control chip U1 is a BP2636 model, which is known for its excellent performance and stability, ensuring that the entire circuit maintains optimal performance under various operating conditions. The step-down section 21 utilizes a combination of transformer LX, fourth capacitor C4, and fourth diode D4, which not only reduces the voltage but also ensures the stability of the output voltage, providing reliable power support for the stable operation of the first control chip U1. The leakage protection section 22, through the cooperation of second diode D2 and leakage protector LD1, can detect abnormal leakage in the circuit in a timely manner and quickly cut off the power supply, thereby avoiding potential dangers such as electric shock or fire and improving the safety of the small power supply. The feedback section 23, through the tenth resistor R10 and eleventh resistor R11, realizes real-time monitoring and feedback of the output voltage, ensuring the stability and reliability of the circuit output. The first sampling section 24, through the combination of fifth resistor R5, sixth resistor R6, and seventh resistor R7, realizes accurate sampling and monitoring of the input current, providing key data support for the protection and control of the circuit.

[0033] Further, please refer to Figure 1 and Figure 2 The lighting driving unit 3 includes a second control chip U2, a first voltage divider 31, and a second voltage divider 32. The input terminal of the first voltage divider 31 is connected to the output terminal of the second filter 13, and the output terminal of the first voltage divider 31 is connected to the ZCD pin of the second control chip U2. The output terminal of the rectifier 12 is connected to the VCC pin of the second control chip U2 through the second voltage divider 32. The DRAIN pin of the second control chip U2 is connected to the output terminal of the leakage protection unit 22 and the input terminal of the output unit 5, respectively.

[0034] Further, please refer to Figure 1 and Figure 2 The lighting driving unit 3 further includes a second sampling unit 33 and an amplification output unit 34; one end of the amplification output unit 34 is connected to the COMP pin of the second control chip U2, and the other end of the amplification output unit 34 is grounded; one end of the second sampling unit 33 is connected to the CS pin of the second control chip U2, and the other end of the second sampling unit 33 is connected to the DIP switch unit 4.

[0035] In this embodiment, the second control chip U2 is model SD6924. The first voltage divider 31 includes a sixteenth resistor R16, a fifteenth resistor R15, and a seventeenth resistor R17. The second voltage divider 32 includes a twelfth resistor R12, a thirteenth resistor R13, and a seventh capacitor C7. The second sampling section 33 includes an eighteenth resistor R18. The amplification output section 34 includes a fifth capacitor C5. One end of the sixteenth resistor R16 is connected to the other end of the second capacitor CY2. The other end of the sixteenth resistor R16 is connected to pin ZCD of the second control chip U2 and pin CY2 of the fourteenth resistor R14 via the fifteenth resistor R15. One end of the fourteenth resistor R14 is connected to the ground; one end of the twelfth resistor R12 is connected to the output terminal of the rectifier bridge BD1, and the other end of the twelfth resistor R12 is connected to the pin VCC of the second control chip U2 and one end of the seventh capacitor C7 through the thirteenth resistor R13, and the other end of the seventh capacitor C7 is grounded; one end of the fifth capacitor C5 is connected to the pin COMP of the second control chip U2, and the other end of the fifth capacitor C5 is grounded; one end of the eighteenth resistor R18 is connected to the pin CS of the second control chip U2, and the other end of the eighteenth resistor R18 is connected to the DIP switch unit 4.

[0036] In this embodiment, the circuit effectively processes and optimizes signals through the cooperation of the voltage divider, sampling section, and amplification output section 34, ensuring the stability and reliability of the circuit. Regarding power management, the connection between the twelfth resistor R12 and the output of the rectifier bridge BD1 ensures a stable DC power supply, which is crucial for maintaining normal circuit operation. Furthermore, the use of the SD6924 second control chip U2 not only reflects the pursuit of high-performance components but also the demand for intelligent and automated circuit control. The second control chip U2 possesses multiple functions, such as overcurrent protection and overvoltage protection, effectively improving the safety and reliability of the circuit. The connection between the eighteenth resistor R18 and the DIP switch unit 4 provides the circuit with more configuration options, allowing for flexible adjustments based on different application scenarios, greatly enhancing the circuit's adaptability and flexibility.

[0037] Further, please refer to Figure 1 and Figure 2The output unit 5 includes a third voltage divider 51, a third filter 52, and a second connector CN2. The input terminal of the third voltage divider 51 is connected to the DRAIN pin of the second control chip U2, and the output terminal of the third voltage divider 51 is connected to the input terminal of the third filter 52. The output terminal of the second filter 13 is connected to the input terminal of the third filter 52, and the output terminal of the third filter 52 is connected to the second connector CN2, which is used to connect lighting fixtures. The DIP switch unit 4 is connected to the third voltage divider 51.

[0038] In this embodiment, the third voltage divider 51 includes a fifth diode D5 and a resistor group consisting of multiple resistors connected in parallel; the third filter 52 includes a third excitation coil LF3; the positive terminal of the fifth diode D5 and one end of the resistor group are respectively connected to the DRAIN pin of the second control chip U2; one end of the resistor group is also connected to the DIP switch unit 4; the output terminal of the rectifier bridge BD1, the negative terminal of the fifth diode D5, and the other end of the resistor group are respectively connected to one end of the third excitation coil LF3; the other end of the third excitation coil LF3 is connected to the second connector CN2, which is used to connect lighting fixtures.

[0039] In this embodiment, the third voltage divider 51 is formed by combining the fifth diode D5 with a resistor group consisting of multiple resistors connected in parallel. This not only saves valuable circuit board space but also provides more adjustment possibilities for the circuit. The parallel design of the resistor group allows engineers to flexibly adjust the resistance value according to different working environments and load requirements, thereby optimizing circuit performance. In addition, the positive terminal of the fifth diode D5 and one end of the resistor group are connected to the DRAIN pin of the second control chip U2. This connection method significantly improves the stability of the circuit. During circuit operation, the synergistic work of the diode and the resistor group can effectively protect the second control chip U2 from voltage fluctuations, ensuring the reliability and long-term stable operation of the circuit. Furthermore, by connecting the DIP switch unit 4 to one end of the resistor group, users can easily adjust the circuit parameters according to actual needs, which not only reduces the difficulty of maintenance but also makes the circuit more user-friendly and can meet the lighting needs of different scenarios. Finally, one end of the third excitation coil LF3 is connected to the output terminal of the rectifier bridge BD1, the negative terminal of the fifth diode D5, and the other end of the resistor group. This connection method ensures that the circuit can be seamlessly integrated with various lighting fixtures.

[0040] Further, please refer to Figure 1 and Figure 2The DIP switch unit 4 includes a first DIP switch section 41 and a second DIP switch section 42. One end of the first DIP switch section 41 and one end of the second DIP switch section 42 are respectively connected to the other end of the second sampling section 33. The other end of the first DIP switch section 41 and the other end of the second DIP switch section 42 are respectively connected to the third voltage divider section 51.

[0041] In this embodiment, the first DIP switch 41 includes a first switch S1, and the second DIP switch 42 includes a second switch S2; one end of the first switch S1 and one end of the second switch S2 are respectively connected to the pin CS of the second control chip U2 through the eighteenth resistor R18, the other end of the first switch S1 is connected to the resistor group through two resistors connected in parallel, and the other end of the second switch S2 is connected to the resistor group through two resistors connected in parallel.

[0042] In this embodiment, one end of the first switch S1 and the second switch S2 is connected to the pin CS of the second control chip U2 through the eighteenth resistor R18. This not only helps to reduce current surges and protect the control chip, but also ensures the stability of the circuit when frequently switching states, ensuring long-term stable operation of the circuit. This reduces maintenance costs and failure rates in practical applications. Regarding resistance adjustment, the other ends of the first switch S1 and the second switch S2 are connected to the resistance group through two parallel resistors, making resistance adjustment extremely convenient. Users can change the circuit parameters through simple switching operations according to actual needs without replacing any hardware components. This not only improves the operability of the circuit, but also provides great convenience to users, making circuit adjustment and optimization more efficient.

[0043] This utility model also provides a PCB board, on which the DIP switch dimming circuit described above is printed.

[0044] Please see Figure 3 The present invention also provides a small power supply, wherein the small power supply uses the DIP switch dimming circuit described above to achieve working control.

[0045] It is understood that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of this utility model, and all such substitutions or changes should fall within the protection scope of this utility model.

Claims

1. A dialing dimming circuit, characterized in that, The input processing unit, constant voltage driving unit, lighting driving unit, dial unit and output unit are connected with each other, and the input terminal of the input processing unit is connected with the external power supply device, the output terminal of the input processing unit is connected with the constant voltage driving unit, the lighting driving unit and the output unit, the drain terminal of the constant voltage driving unit is connected with the drain terminal of the lighting driving unit, the drain terminal of the lighting driving unit is also connected with the input terminal of the output unit, the dial unit is connected with the sampling terminal of the lighting driving unit and the output unit, and the output terminal of the output unit is connected with the lighting device.

2. The dialing dimmer circuit according to claim 1, wherein, The input processing unit includes a first plug CN1, a first filter, a rectifier and a second filter, the first plug CN1 is used for connecting the external power supply device, the first plug CN1 is also connected with the input terminal of the first filter, the output terminal of the first filter is connected with the input terminal of the rectifier, the output terminal of the rectifier is connected with the power supply terminal of the constant voltage driving unit, the lighting driving unit and the input terminal of the second filter, and the output terminal of the second filter is connected with the output unit.

3. The dialing dimmer circuit according to claim 2, wherein, The constant voltage driving unit includes a voltage reduction part, a leakage protection part and a first control chip U1, the input terminal of the voltage reduction part is connected with the output terminal of the rectifier, the output terminal of the voltage reduction part is connected with the pin VCC of the first control chip U1, and the pin D of the first control chip U1 is connected with the drain terminal of the lighting driving unit through the leakage protection part.

4. The dialing dimmer circuit according to claim 3, wherein, The constant voltage driving unit also includes a feedback part and a first sampling part, the input terminal of the feedback part is connected with the output terminal of the leakage protection part, the output terminal of the feedback part is connected with the pin FB of the first control chip U1, one end of the sampling part is connected with the pin CS of the first control chip U1, and the other end of the sampling part is grounded.

5. The dialing dimmer circuit according to claim 3, wherein, The lighting driving unit includes a second control chip U2, a first voltage division part and a second voltage division part, the input terminal of the first voltage division part is connected with the output terminal of the second filter, the output terminal of the first voltage division part is connected with the pin ZCD of the second control chip U2, the output terminal of the rectifier is connected with the pin VCC of the second control chip U2 through the second voltage division part, and the pin DRAIN of the second control chip U2 is connected with the output terminal of the leakage protection part and the input terminal of the output unit.

6. The dialing dimmer circuit according to claim 5, wherein, The lighting driving unit also includes a second sampling part and an amplification output part, one end of the amplification output part is connected with the pin COMP of the second control chip U2, the other end of the amplification output part is grounded, one end of the second sampling part is connected with the pin CS of the second control chip U2, and the other end of the second sampling part is connected with the dial unit.

7. The dialing dimmer circuit according to claim 6, wherein, The output unit comprises a third voltage dividing part, a third filter part and a second connector CN2; the input end of the third voltage dividing part is connected with the pin DRAIN of the second control chip U2, and the output end of the third voltage dividing part is connected with the input end of the third filter part; the output end of the second filter part is connected with the input end of the third filter part, the output end of the third filter part is connected with the second connector CN2, and the second connector CN2 is used for connecting a lighting lamp; the code dial unit is connected with the third voltage dividing part.

8. The dialing dimmer circuit according to claim 7, wherein, The code dial unit comprises a first code dial part and a second code dial part, one end of the first code dial part and one end of the second code dial part are respectively connected with the other end of the second sampling part, and the other end of the first code dial part and the other end of the second code dial part are respectively connected with the third voltage dividing part.

9. A PCB board characterized by, The PCB is printed with the code dial dimming circuit as claimed in any one of claims 1-8.

10. A small power supply characterized by comprising: The small power supply realizes work control by using the code dial dimming circuit as claimed in any one of claims 1-8.

Images