Phototherapy instrument and LED lamp driving circuit thereof

Abstract

The utility model discloses a phototherapy instrument and an LED lamp driving circuit thereof. The LED lamp driving circuit comprises a control module, a driving module, a sampling module and a monitoring module. The control module outputs a PWM control signal to the driving module, the driving module drives the LED lamp to be turned on, and the monitoring module collects a first voltage value through the sampling module and sends the first voltage value to the control module, so that the control module adjusts the PWM control signal. According to the technical scheme, flexible control over the brightness of the LED lamp is achieved through PWM control signal adjustment, the LED lamp is suitable for different phototherapy application scenes, the working state of the LED lamp can be continuously collected and fed back through cooperative work of the sampling module and the monitoring module, and the stability of voltage is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of physical therapy devices, in particular to a light therapy device and an LED lamp driving circuit thereof. Background Art

[0002] Existing electronic devices, especially those like phototherapy devices, often require controlling the brightness of LED lights or the operating status of other loads. These devices require precise control of voltage and current, especially in unstable power supply environments or with complex load characteristics. Voltage fluctuations or excessive current can affect device stability and even damage components. Furthermore, with increasing market demand for consumer products like phototherapy devices, the industry's requirements for circuit design are gradually increasing, requiring not only a wide range of applications but also low cost and high reliability.

[0003] Traditional circuit designs often struggle to achieve both stability and flexibility, resulting in complex and costly circuit designs. Furthermore, existing solutions can easily cause equipment failures or safety hazards when faced with issues like unstable voltage or excessive current, reducing product reliability in practical applications. Therefore, a control circuit with simultaneous voltage and current monitoring and automatic adjustment capabilities is urgently needed to ensure stable and safe performance in diverse operating environments. Utility Model Content

[0004] The embodiment of the present utility model provides a light therapy device and an LED lamp driving circuit thereof to solve the above-mentioned technical problems.

[0005] A first aspect of an embodiment of the present invention provides an LED lamp driving circuit for a phototherapy device, comprising: a control module, a driving module, a sampling module, and a monitoring module;

[0006] The output end of the control module is connected to the input end of the driving module, the output end of the driving module is connected to one end of the sampling module, the other end of the sampling module is connected to the LED lamp module, the two input ends of the monitoring module are respectively connected to the two ends of the sampling module, and the output end of the monitoring module is connected to the first input end of the control module;

[0007] The control module outputs a PWM control signal to the driving module, and the driving module drives the LED lamp to light up. The monitoring module collects a first voltage value through the sampling module and sends the first voltage value to the control module, so that the control module adjusts the PWM control signal.

[0008] Optionally, the driving module further includes a detection end, and the detection end of the driving module is connected to the second input end of the control module;

[0009] The control module obtains a second voltage value of the detection terminal of the driving module to adjust the PWM control signal.

[0010] Optionally, the driving module includes a first operational amplifier, a first filtering module, and a first feedback module, the input end of the first filtering module is the first input end of the driving module, and the output end of the first filtering module is connected to the non-inverting input end of the first operational amplifier;

[0011] The input end of the first feedback module is connected to the output end of the first operational amplifier, the first output end of the first feedback module is connected to the inverting input end of the first operational amplifier, and the second output end of the first feedback module is the detection end of the driving module.

[0012] Optionally, the first filtering module includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, an eleventh capacitor and a twelfth capacitor, one end of the eleventh resistor is the input end of the first filtering module, the other end of the eleventh resistor is respectively connected to one end of the eleventh capacitor and one end of the twelfth resistor, the other end of the eleventh capacitor is grounded, the other end of the twelfth resistor is connected to one end of the thirteenth resistor, the other end of the thirteenth resistor and one end of the twelfth capacitor are connected together as the output end of the first filtering module, and the other end of the twelfth capacitor is grounded.

[0013] Optionally, the first feedback module includes a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor and a thirteenth capacitor, one end of the fourteenth resistor, one end of the fifteenth resistor and one end of the thirteenth capacitor are commonly connected as the second output end of the first feedback module, the other end of the fourteenth resistor and one end of the sixteenth resistor are commonly connected as the input end of the first feedback module, the other end of the sixteenth resistor and one end of the seventeenth resistor are commonly connected as the first output end of the first feedback module, and the other end of the thirteenth capacitor, the other end of the fifteenth resistor and the other end of the seventeenth resistor are commonly connected to ground.

[0014] Optionally, the monitoring module includes a second filtering module, a third filtering module, a fourth filtering module, a second feedback module and a second operational amplifier, one end of the second filtering module is the first input end of the monitoring module, the other end of the second filtering module is respectively connected to the inverting input end of the second operational amplifier and the output end of the second feedback module, one end of the third filtering module is the second input end of the monitoring module, the other end of the third filtering module is connected to the non-inverting input end of the second operational amplifier, the output end of the second operational amplifier is respectively connected to the input end of the second feedback module and one end of the fourth filtering module, and the other end of the fourth filtering module is the output end of the monitoring module.

[0015] Optionally, the second filtering module includes a first resistor, a second resistor, and a first capacitor, one end of the first resistor is one end of the second filtering module, the other end of the first resistor is respectively connected to one end of the first capacitor and one end of the second resistor, the other end of the second resistor is the other end of the second filtering module, and the other end of the first capacitor is grounded;

[0016] The third filtering module includes a third resistor, a fourth resistor, a fifth resistor and a second capacitor, one end of the third resistor is one end of the third filtering module, the other end of the third resistor is respectively connected to one end of the second capacitor and one end of the fourth resistor, the other end of the fourth resistor and one end of the fifth resistor are commonly connected to the other end of the third filtering module, the other end of the second capacitor is grounded, and the other end of the fifth resistor is grounded.

[0017] Optionally, the second feedback module includes a sixth resistor and a third capacitor, one end of the sixth resistor and one end of the third capacitor are commonly connected as an input end of the second feedback module, and the other end of the sixth resistor and the other end of the third capacitor are commonly connected as an output end of the second feedback module;

[0018] The fourth filtering module includes a seventh resistor, an eighth resistor and a fourth capacitor. One end of the seventh resistor and one end of the eighth resistor are connected together as one end of the fourth filtering module, the other end of the eighth resistor and one end of the fourth capacitor are connected together as the other end of the fourth filtering module, the other end of the fourth capacitor is grounded, and the other end of the seventh resistor is grounded.

[0019] A second aspect of an embodiment of the present invention provides a light therapy device, comprising: the LED lamp driving circuit and LED lamp module described in the first aspect.

[0020] The technical effects of the embodiments of this utility model are as follows: PWM control signal adjustment enables flexible control of LED lamp brightness, suitable for different phototherapy application scenarios. The collaborative operation of the sampling module and the monitoring module can continuously collect and provide feedback on the operating status of the LED lamp, ensuring voltage stability. This circuit structure is simple, flexible, and low-cost, suitable for products such as phototherapy devices that require LED lamp driving, and has broad application prospects. In addition, this solution achieves efficient and low-cost LED lamp driving while ensuring circuit stability and safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0022] Figure 1 This is a first structural diagram of an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0023] Figure 2 This is a second structural diagram of an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0024] Figure 3 This is a structural diagram of a driving module in an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0025] Figure 4 This is a circuit diagram of a driving module in an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0026] Figure 5 This is a structural diagram of a monitoring module in an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0027] Figure 6 This is a circuit diagram of a monitoring module in an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0028] Figure 7 This is a circuit diagram of a control module in an LED lamp driving circuit provided by the first embodiment of the present utility model;

[0029] In the figure: 10, LED lamp driving circuit; 20, LED lamp module; 101, control module; 102, driving module; 103, sampling module; 104, monitoring module; 121, first operational amplifier; 122, first filtering module; 123, first feedback module; 141, second filtering module; 142, third filtering module; 143, fourth filtering module; 144, second feedback module; 145, second operational amplifier. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] It should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to make the disclosure thorough and complete and to fully convey the scope of the present invention to those skilled in the art. In the drawings, the dimensions and relative dimensions of layers and regions may be exaggerated for clarity. Like reference numerals denote like elements throughout.

[0032] It should be understood that when an element or layer is referred to as being "on," "adjacent to," "connected to," or "coupled to" another element or layer, it may be directly on, adjacent to, connected to, or coupled to the other element or layer, or there may be intervening elements or layers. Conversely, when an element is referred to as being "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, or part from another element, component, region, layer, or part. Therefore, without departing from the teachings of the present invention, the first element, component, region, layer, or part discussed below may be represented as a second element, component, region, layer, or part.

[0033] Spatially relative terms such as "under," "beneath," "below," "under," "above," "above," etc., may be used herein for convenience of description to describe the relationship of one element or feature shown in the figures to other elements or features. It should be understood that the spatially relative terms are intended to include different orientations of the device in use and operation in addition to the orientations shown in the figures. For example, if the device in the drawings is flipped, then the elements or features described as "under" or "beneath" or "beneath" the other elements will be oriented as "over" the other elements or features. Thus, the exemplary terms "under" and "under" may include both the upper and lower orientations. The device may be oriented otherwise (rotated 90 degrees or in other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0034] The purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present invention. When used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0035] In order to fully understand the present invention, the following description will provide detailed structures and steps to illustrate the technical solutions proposed by the present invention. The preferred embodiments of the present invention are described in detail below. However, in addition to these detailed descriptions, the present invention may also have other implementation methods.

[0036] Example 1

[0037] The first embodiment of the present invention provides a LED lamp driving circuit for a light therapy device, such as Figure 1 As shown, it includes: a control module 101, a driving module 102, a sampling module 103 and a monitoring module 104;

[0038] The output end of the control module 101 is connected to the input end of the driving module 102, the output end of the driving module 102 is connected to one end of the sampling module 103, the other end of the sampling module 103 is connected to the LED lamp module, the two input ends of the monitoring module 104 are respectively connected to the two ends of the sampling module 103, and the output end of the monitoring module 104 is connected to the first input end of the control module 101;

[0039] The control module 101 outputs a PWM control signal to the driving module 102, and the driving module 102 drives the LED lamp to light up. The monitoring module 104 collects the first voltage value through the sampling module 103 and sends the first voltage value to the control module 101, so that the control module 101 adjusts the PWM control signal.

[0040] The LED light driver circuit of the phototherapy device consists of four main modules: a control module 101, a driver module 102, a sampling module 103, and a monitoring module 104. Each module performs different functions and roles within the overall circuit. The control module 101 generates a PWM (pulse width modulation) control signal and adjusts the current output by the driver module 102 by adjusting the duty cycle of the PWM control signal, thereby controlling the brightness of the LED light. After receiving voltage information feedback from the monitoring module 104, the control module 101 automatically adjusts the PWM control signal to maintain stable brightness or to turn off the LED light. The driver module 102 receives the PWM control signal from the control module 101 and converts it into a driving current, directly driving the LED light. The sampling module 103 collects the voltage output from the driver module 102 to the LED light module 20. Simultaneously, the voltage signal from the sampling module 103 is transmitted to the monitoring module 104 for feedback on the system's operating status. The monitoring module 104 receives the voltage data transmitted by the sampling module 103, processes the collected voltage value, and outputs a feedback signal to the control module 101. The control module 101 adjusts the PWM control signal according to the feedback signal, thereby maintaining a stable brightness of the LED lamp or performing a extinguishing operation.

[0041] The technical effect of this embodiment is that: through PWM control signal adjustment, flexible control of the brightness of the LED lamp is achieved, which is suitable for different phototherapy application scenarios. Through the collaborative work of the sampling module and the monitoring module, the working status of the LED lamp can be continuously collected and fed back to ensure the stability of the voltage. When a voltage abnormality is detected, the system can automatically execute protection measures, such as adjusting the PWM control signal or turning off the LED lamp to avoid equipment damage, thereby improving the reliability and safety of the system. The circuit structure is simple, flexible, and low-cost. It is suitable for products such as phototherapy devices that require LED lamp driving and has broad application prospects. In addition, this solution realizes efficient and low-cost LED lamp driving while ensuring the stability and safety of the circuit.

[0042] As an embodiment, the control module 101 maintains the LED lamp module in a lighting state when it detects that the first voltage value is within the preset voltage range; and controls the LED lamp module to be extinguished when it detects that the first voltage value is not within the preset voltage range.

[0043] When this circuit begins operation, the control module 101 generates and outputs a PWM control signal to the driver module 102. The driver module 102 adjusts the output current according to the duty cycle of the PWM control signal to illuminate the LED lamp module 20, causing the LED lamp module 20 to begin operating and emit light. The sampling module 103 collects the voltage signal output from the driver module 102 to the LED lamp module 20 in real time and transmits the collected voltage value to the monitoring module 104. The monitoring module 104 feeds the collected voltage value back to the control module 101 for comparison with a preset voltage range. If the control module 101 detects that the collected voltage value is within the preset voltage range, it indicates that the LED lamp module 20 is operating normally. The control module 101 continues to output the PWM control signal, maintaining the output of the driver module 102, and the LED lamp module 20 continues to illuminate stably. If the control module 101 detects that the collected voltage value is outside the preset voltage range (e.g., the voltage is too high or too low), it determines that the LED lamp module 20 is operating abnormally. At this time, the control module 101 will immediately stop outputting the PWM control signal, the output current of the driving module 102 will stop, and the LED lamp module 20 will be turned off.

[0044] The technical effect of this embodiment is to ensure that the LED lamp module does not continue to operate under abnormal voltage, thereby avoiding damage or unsafe conditions caused by overvoltage or undervoltage.

[0045] As an implementation method, Figure 2 As shown, the driving module 102 further includes a detection end, and the detection end of the driving module 102 is connected to the second input end of the control module 101;

[0046] The control module 101 obtains a second voltage value of the detection terminal of the driving module 102 to adjust the PWM control signal.

[0047] This embodiment adds a detection terminal of the driver module 102 connected to the second input terminal of the control module 101, forming a closed-loop feedback control system. This allows the control module 101 to not only monitor the voltage of the LED lamp module 20 via the sampling module 103 but also directly obtain voltage information from the driver circuit via the detection terminal of the driver module 102, thereby more accurately adjusting the PWM control signal output. The control module 101 generates a PWM control signal at its output terminal and transmits this control signal to the input terminal of the driver module 102. The driver module 102 adjusts the output current based on the PWM control signal from the control module 101, illuminating the LED lamp module 20. At this point, the output voltage of the driver module 102 varies according to the duty cycle of the PWM control signal, providing the corresponding driving voltage to the LED lamp module 20. The driver module 102 also has a detection terminal for real-time acquisition of changes in the output voltage of the driver module 102. Based on the voltage value detected by the driver module 102 and the actual voltage signal obtained from the monitoring module 104, the control module 101 determines whether the driving voltage is within a preset range. The control module 101 compares the second voltage value detected from the driver module 102 with a preset voltage range. If the driving voltage deviates, the control module 101 automatically adjusts the duty cycle of the PWM control signal it outputs to correct the current and voltage output by the driver module 102. For example, if the second voltage value is detected to be too high, the control module 101 will reduce the duty cycle of the PWM control signal, thereby reducing the output current of the driver module 102 and preventing the LED lamp module 20 from being overbright or damaged. Conversely, if the second voltage value is detected to be too low, the control module 101 will increase the duty cycle of the PWM control signal to increase the output current and ensure the normal brightness of the LED lamp module 20. The driver module 102 continuously feeds back the actual output voltage to the control module 101, and the control module 101 dynamically adjusts the duty cycle of the PWM control signal based on the feedback signal to ensure that the driving voltage always remains within a reasonable range. This forms a real-time closed-loop control system. If, during the closed-loop control process, it is detected that the voltage of the driver module 102 exceeds a preset range (eg, overvoltage or undervoltage), the control module 101 will quickly correct it by adjusting the PWM control signal to ensure the stability and safety of the LED lamp.

[0048] The technical benefit of this embodiment is that, by adding a detection terminal to the driver module, the control module can directly obtain information about the driver module's actual output voltage and adjust the PWM control signal accordingly. This dual monitoring mechanism improves the accuracy of voltage control. Real-time adjustment of the PWM control signal ensures that the LED lamp module maintains a stable voltage output under various operating conditions, effectively preventing brightness instability caused by voltage fluctuations.

[0049] As an implementation method, Figure 3As shown, the driving module 102 includes a first operational amplifier 121, a first filtering module 122 and a first feedback module 123. The input end of the first filtering module 122 is the input end of the driving module 102, and the output end of the first filtering module 122 is connected to the non-inverting input end of the first operational amplifier 121.

[0050] The input end of the first feedback module 123 is connected to the output end of the first operational amplifier 121 , the first output end of the first feedback module 123 is connected to the inverting input end of the first operational amplifier 121 , and the second output end of the first feedback module 123 is the detection end of the driving module 102 .

[0051] Among them, the first filtering module 122 receives the PWM control signal or other control signal from the control module 101. This module filters the input PWM control signal through a filtering circuit composed of components such as resistors and capacitors, smoothes the signal waveform, removes high-frequency noise, and makes the signal more stable and suitable for subsequent circuits. The output end of the filtered signal is connected to the non-inverting input end of the first operational amplifier 121 to provide a stable input signal. The first operational amplifier 121 receives the filtered stable signal, performs voltage amplification according to the input signal, and amplifies the input adjustment signal to the required driving voltage or current for driving the LED lamp module 20 to light up. The first feedback module 123 obtains the voltage or current signal output by the first operational amplifier 121, and feeds back the output signal of the first operational amplifier 121 to the inverting input end of the first operational amplifier 121 to form a negative feedback control loop. This process ensures that the first operational amplifier 121 can adjust and stabilize the output signal to prevent the output voltage from being too high or too low. The second output terminal of the first feedback module 123 serves as a detection terminal of the driving module 102 and is connected to the second input terminal of the control module 101 , for providing real-time output voltage information of the driving module 102 and feeding it back to the control module 101 .

[0052] The technical effect of this embodiment is that, through the interaction of the first filter module, the first operational amplifier, and the first feedback module, a stable and efficient LED lamp driving system is formed. The first filter module filters the input signal, the first operational amplifier provides sufficient driving voltage, and the first feedback module implements closed-loop control through a negative feedback mechanism and real-time detection terminal feedback, ensuring precise brightness control of the LED lamp module and system safety and stability.

[0053] As an example, Figure 4As shown, the first filtering module 122 includes an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, an eleventh capacitor C11 and a twelfth capacitor C12, one end of the eleventh resistor R11 is the input end of the first filtering module 122, the other end of the eleventh resistor R11 is respectively connected to one end of the eleventh capacitor C11 and one end of the twelfth resistor R12, the other end of the eleventh capacitor C11 is grounded, the other end of the twelfth resistor R12 is connected to one end of the thirteenth resistor R13, the other end of the thirteenth resistor R13 and one end of the twelfth capacitor C12 are commonly connected as the output end of the first filtering module 122, and the other end of the twelfth capacitor C12 is grounded.

[0054] Among them, the eleventh resistor R11 receives the PWM control signal from the control module 101. The PWM control signal will carry high-frequency components and noise during the transmission process. The eleventh resistor R11 and the eleventh capacitor C11 together form a first-order RC low-pass filter, which preliminarily filters out the high-frequency noise in the input signal, suppresses the high-frequency components, plays a role in signal smoothing, and provides a filtered signal source for subsequent circuits. The twelfth resistor R12 further performs current limiting processing on the signal. The thirteenth resistor R13 and the twelfth capacitor C12 together form a second-order RC low-pass filter. The twelfth capacitor C12 short-circuits the high-frequency signal to ground, allowing the low-frequency signal to pass smoothly, further attenuating the high-frequency noise. The signal after two-stage filtering is finally output from the connection point of the twelfth capacitor C12 and the thirteenth resistor R13, becoming a filtered smooth signal, and sent to the first operational amplifier U2 for subsequent processing.

[0055] The technical benefit of this embodiment lies in: through a two-stage RC low-pass filtering design, the module effectively filters out high-frequency noise and interference from the input signal, ensuring high signal purity during transmission. The high-frequency components of the input signal are limited, preventing them from affecting the subsequent LED driving and control processes. The filtered signal is smoother and more stable, effectively preventing problems such as flickering and uneven brightness in the LED lights.

[0056] As an example, Figure 4 As shown, the first feedback module 123 includes a fourteenth resistor R14, a fifteenth resistor R15, a sixteenth resistor R16, a seventeenth resistor R17, and a thirteenth capacitor C13. One end of the fourteenth resistor R14, one end of the fifteenth resistor R15, and one end of the thirteenth capacitor C13 are commonly connected to form a second output end of the first feedback module 123. The other end of the fourteenth resistor R14 and one end of the sixteenth resistor R16 are commonly connected to form an input end of the first feedback module 123. The other end of the sixteenth resistor R16 and one end of the seventeenth resistor R17 are commonly connected to form a first output end of the first feedback module 123. The other end of the thirteenth capacitor C13, the other end of the fifteenth resistor R15, and the other end of the seventeenth resistor R17 are commonly connected to ground.

[0057] Among them, the fourteenth resistor R14 limits the current of the feedback signal from the driver module 102, and at the same time forms a voltage divider network with the fifteenth resistor R15 to transmit the signal to the control module 101. The fourteenth resistor R14 is mainly used to adjust the level of the feedback signal to ensure that the feedback signal is suitable for subsequent processing and detection. Through the resistance characteristics of the fourteenth resistor R14, the signal can be effectively shunted to prevent excessive feedback signals from directly entering the control module 101 or the first operational amplifier U2. The sixteenth resistor R16 and the fourteenth resistor R14 jointly receive the feedback signal and transmit the signal to the inverting input terminal of the first operational amplifier 121. The seventeenth resistor R17 and the sixteenth resistor R16 constitute part of the negative feedback path. The seventeenth resistor R17 further limits the current of the feedback signal to ensure stable operation of the feedback loop. The thirteenth capacitor C13 forms a filter circuit, which is mainly used to filter out high-frequency noise from the feedback signal to ensure that the signal is interference-free. The control module 101 and the first operational amplifier U2 can receive a more stable feedback signal to ensure the signal quality and reliability of the entire circuit.

[0058] The technical effect of this embodiment is that: through the combination of the fourteenth resistor, the fifteenth resistor, the sixteenth resistor, the seventeenth resistor and the thirteenth capacitor, a precise negative feedback and signal detection mechanism is formed, which can not only effectively filter the signal, but also transmit the feedback signal to the first operational amplifier and the control module, thereby ensuring stable and efficient operation of the system.

[0059] As an example, Figure 4 As shown, the sampling module 103 includes an eighteenth resistor R18 and a sixteenth capacitor C16. One end of the eighteenth resistor R18 and one end of the sixteenth capacitor C16 are connected together to form one end of the sampling module 103. One end of the eighteenth resistor R18 and the other end of the sixteenth capacitor C16 are connected together to form the other end of the sampling module 103.

[0060] The eighteenth resistor R18 acts as a sampling resistor, measuring the current flowing through it and converting it into a voltage signal, which is then passed to subsequent circuits for processing. The sixteenth capacitor C16 is connected in parallel with the eighteenth resistor R18 to smooth voltage fluctuations and provide voltage stabilization.

[0061] Furthermore, one end of the sampling module 103 is also connected to one end of the fourteenth capacitor C14, one end of the fifteenth capacitor C15 and the anode of the LED lamp D1 respectively, the other end of the fourteenth capacitor C14 and the other end of the fifteenth capacitor C15 are connected to the ground, and the cathode of the LED lamp D1 is grounded.

[0062] The fourteenth capacitor C1 and the fifteenth capacitor C15 are used to stabilize the voltage of the LED lamp D1 .

[0063] As an implementation method, Figure 5 As shown, the monitoring module 104 includes a second filter module 141, a third filter module 142, a fourth filter module 143, a second feedback module 144 and a second operational amplifier 145. One end of the second filter module 141 is the first input end of the monitoring module 104, and the other end of the second filter module 141 is respectively connected to the inverting input end of the second operational amplifier 145 and the output end of the second feedback module 144. One end of the third filter module 142 is the second input end of the monitoring module 104, and the other end of the third filter module 142 is connected to the non-inverting input end of the second operational amplifier 145. The output end of the second operational amplifier 145 is respectively connected to the input end of the second feedback module 144 and one end of the fourth filter module 143. The other end of the fourth filter module 143 is the output end of the monitoring module 104.

[0064] The second filtering module 141 receives a feedback signal or a voltage detection signal and filters the input signal, primarily removing high-frequency noise and transient interference from the signal, thereby outputting a stable low-frequency signal. The third filtering module 142 receives a feedback signal source or a voltage detection signal. Similar to the second filtering module 141, this module primarily filters the input signal. The second operational amplifier 145 receives the filtered signal and processes it as an input signal. Meanwhile, its non-inverting input terminal is connected to the output terminal of the third filtering module 142, providing a reference signal. The second operational amplifier 145 performs differential processing on the input inverted and non-inverted signals, outputting an amplified signal reflecting the signal difference. The second feedback module 144 forms a feedback loop for adjusting the gain and stability of the second operational amplifier 145. By providing feedback on the output signal of the second operational amplifier 145, the second feedback module 144 controls the output stability of the second operational amplifier 145.

[0065] The technical effect of this embodiment is that through the coordinated work of the second filtering module, the third filtering module, the fourth filtering module, the second feedback module and the second operational amplifier, an efficient and accurate signal monitoring and feedback control system is formed, which can effectively filter out noise, amplify weak signal changes, and provide a stable output signal. It is suitable for application circuits with high requirements on signal stability and accuracy, such as precise control and monitoring in LED drive circuits.

[0066] As an example, Figure 6As shown, the second filtering module 141 includes a first resistor R1, a second resistor R2 and a first capacitor C1, one end of the first resistor R1 is one end of the second filtering module 141, the other end of the first resistor R1 is respectively connected to one end of the first capacitor C1 and one end of the second resistor R2, the other end of the second resistor R2 is the other end of the second filtering module 141, and the other end of the first capacitor C1 is grounded.

[0067] The first resistor R1 receives the sampled signal and connects to the first capacitor C1, forming an RC low-pass filter circuit. This circuit primarily limits current and, in combination with the capacitor, performs primary filtering of the signal, reducing high-frequency components. The second resistor R2 further limits and filters the input signal, passing the filtered signal to subsequent circuits.

[0068] The technical advantage of this embodiment is that the combination of the first resistor, the second resistor, and the first capacitor forms an effective RC low-pass filter circuit, effectively filtering out high-frequency noise and interference from the input signal, ensuring signal smoothness and stability, and enhancing the system's anti-interference capability. The filtered signal can be more accurately processed by subsequent circuits, making it suitable for applications requiring signal stability and strong anti-interference capabilities.

[0069] As an example, Figure 6 As shown, the third filtering module 142 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5 and a second capacitor C2. One end of the third resistor R3 is one end of the third filtering module 142, and the other end of the third resistor R3 is respectively connected to one end of the second capacitor C2 and one end of the fourth resistor R4. The other end of the fourth resistor R4 and one end of the fifth resistor R5 are commonly connected to the other end of the third filtering module 142. The other end of the second capacitor C2 is grounded, and the other end of the fifth resistor R5 is grounded.

[0070] The third resistor R3 and the second capacitor C2 together form a first-order RC low-pass filter, which initially filters out high-frequency noise and spike interference in the input signal. The fourth resistor R4 limits and processes the signal after the initial filtering. The fifth resistor R5 further limits the current to ensure signal stability.

[0071] The technical effect of this embodiment is that an RC low-pass filter circuit is formed by the combination of the third resistor, the fourth resistor, the fifth resistor and the second capacitor, which can effectively filter out high-frequency noise in the input signal and ensure the smoothness and stability of the signal.

[0072] As an example, Figure 6As shown, the second feedback module 144 includes a sixth resistor R6 and a third capacitor C3, one end of the sixth resistor R6 and one end of the third capacitor C3 are commonly connected as the input end of the second feedback module 144, and the other end of the sixth resistor R6 and the other end of the third capacitor C3 are commonly connected as the output end of the second feedback module 144.

[0073] The sixth resistor R6 receives the output signal from the second operational amplifier U3. Its primary function is to limit the feedback current, adjust the strength of the feedback signal, and ensure that the signal is stably fed back to the input terminal, thereby adjusting the gain of the second operational amplifier U3. The third capacitor C3 is connected in series with the sixth resistor R6 to form another part of the feedback loop.

[0074] The technical effect of this embodiment is that the output stability of the operational amplifier is ensured by regulating and filtering the feedback signal, thereby enabling the second operational amplifier to obtain a stable feedback signal, thereby maintaining the accuracy and stability of its output.

[0075] As an example, Figure 6 As shown, the fourth filtering module 143 includes a seventh resistor R7, an eighth resistor R8 and a fourth capacitor C4. One end of the seventh resistor R7 and one end of the eighth resistor R8 are connected together as one end of the fourth filtering module 143, the other end of the eighth resistor R8 and one end of the fourth capacitor C4 are connected together as the other end of the fourth filtering module 143, the other end of the fourth capacitor C4 is grounded, and the other end of the seventh resistor R7 is grounded.

[0076] The eighth resistor R8 is connected in series with the seventh resistor R7 and, together with the fourth capacitor C4, forms part of an RC filter circuit. The eighth resistor R8 and the fourth capacitor C4 work together to further attenuate high-frequency noise in the signal. The primary function of the fourth capacitor C4 is to present a low impedance at high frequencies, short-circuiting the high-frequency components to ground, thereby filtering out high-frequency noise in the signal.

[0077] The technical effect of this embodiment is that an effective first-order RC low-pass filter circuit is formed by the combination of the seventh resistor, the eighth resistor and the fourth capacitor, which can effectively filter out high-frequency noise in the signal and ensure the smoothness and stability of the signal.

[0078] As an implementation method, Figure 7 As shown, the control module 101 is the first chip U1. Figure 4 、 Figure 6 as well as Figure 7 The working process of this embodiment is described as follows:

[0079] When the circuit starts working, the 12th pin (PA6) of the first chip U1 is controlled by PWM1. The relative duty cycle is adjusted by software to synchronously output a corresponding pulse to the non-inverting input terminal of the operational amplifier (point A voltage). At this time, the RC filter circuit composed of the eleventh resistor R11, the twelfth resistor R12, the thirteenth resistor R13, the eleventh capacitor C11 and the twelfth capacitor C12 enters the non-inverting input terminal of the first operational amplifier U2. After the non-inverting operational amplification, the corresponding voltage is output. At this time, the LED lamp D1 lights up; the 16th pin (PB2) of the first chip U1 is synchronized, and after detecting the voltage value corresponding to point B, the feedback signal is synchronously given to the first chip U1 to adjust the PWM1 output duty cycle of the first chip U1's pin 12, so as to output the stable voltage value required by the LED lamp D1 after passing through the first operational amplifier U2, so that the LED lamp D1 can be kept lit normally. When the LED lamp D1 is normally lit, the voltage values ​​at points C and D are sampled through the sampling resistor R18, and are input to the non-inverting input and inverting input of the differential operational amplifier U3 through the filter circuit consisting of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the first capacitor C1, and the second capacitor C2. After differential amplification, the corresponding voltage value (the voltage at point F) is output, and the RC filter circuit consisting of the seventh resistor R7 and the fourth capacitor C4 is used to perform AD detection through the 15th pin (PB1) of the first chip U1. When the AD sampling value meets the set parameter value, the LED lamp D1 remains on; when the AD sampling value is too large and exceeds the set value, the system is directly shut down and the LED lamp D1 is extinguished, ensuring the safety of the entire system circuit.

[0080] Among them, the voltage calculation formula at each point is:

[0081] 1. Point A voltage: The default input voltage is UIN_A.

[0082] 2. Voltage at point B: VOUT_B = VOUT_C ​​× (R15 / (R14+R15)).

[0083] 3. Voltage at point C: VOUT_C ​​= VIN_A × (1 + R17 / R16).

[0084] 4. D = voltage at point E: VOUT_D = VOUT_C ​​× (R / (R18 + R)), where VF is the forward voltage of the LED lamp, IF is the forward current, and R = VF / IF.

[0085] 5. Set R3 = R4, R5 = R6, and the voltage at point F is: VOUT_F = R6 / R3 × (VOUT_C ​​- VOUT_D).

[0086] Example 2

[0087] The second embodiment provides a light therapy device, including the LED lamp driving circuit and LED lamp module provided in the first embodiment.

[0088] The phototherapy device provided in the second embodiment adopts the LED lamp driving circuit provided in the first embodiment. This circuit is powered by a single power supply and includes an operational amplifier, a capacitor, a resistor, an LED lamp and a single-chip microcomputer. Through the single-chip microcomputer control, voltage ADC acquisition and differential sampling, an interaction is formed to control the normal lighting of the load LED lamp. This circuit can be used to collect both AC voltage and DC voltage. It has a wide effective bandwidth, low cost, and flexible configuration. It is suitable for the application of related products such as phototherapy devices. The use of this circuit can better solve the problems of unstable voltage and excessive current in the current circuit, which lead to unstable product performance or damage to related devices and products. This circuit ensures the performance stability and safety of the product during use.

[0089] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the scope of protection of the present invention.

Claims

1. A LED lamp driving circuit for a phototherapy device, characterized in that: include: Control module, drive module, sampling module and monitoring module; The output end of the control module is connected to the input end of the driving module, the output end of the driving module is connected to one end of the sampling module, the other end of the sampling module is connected to the LED lamp module, the two input ends of the monitoring module are respectively connected to the two ends of the sampling module, and the output end of the monitoring module is connected to the first input end of the control module; The control module outputs a PWM control signal to the driving module, and the driving module drives the LED lamp to light up. The monitoring module collects a first voltage value through the sampling module and sends the first voltage value to the control module, so that the control module adjusts the PWM control signal.

2. The LED lamp driving circuit according to claim 1, wherein: The driving module further includes a detection end, and the detection end of the driving module is connected to the second input end of the control module; The control module obtains a second voltage value of the detection terminal of the driving module to adjust the PWM control signal.

3. The LED lamp driving circuit according to claim 2, wherein: The driving module includes a first operational amplifier, a first filtering module and a first feedback module, the input end of the first filtering module is the input end of the driving module, and the output end of the first filtering module is connected to the non-inverting input end of the first operational amplifier; The input end of the first feedback module is connected to the output end of the first operational amplifier, the first output end of the first feedback module is connected to the inverting input end of the first operational amplifier, and the second output end of the first feedback module is the detection end of the driving module.

4. The LED lamp driving circuit according to claim 3, wherein: The first filtering module includes an eleventh resistor, a twelfth resistor, a thirteenth resistor, an eleventh capacitor and a twelfth capacitor. One end of the eleventh resistor is the input end of the first filtering module, the other end of the eleventh resistor is respectively connected to one end of the eleventh capacitor and one end of the twelfth resistor, the other end of the eleventh capacitor is grounded, the other end of the twelfth resistor is connected to one end of the thirteenth resistor, the other end of the thirteenth resistor and one end of the twelfth capacitor are connected together as the output end of the first filtering module, and the other end of the twelfth capacitor is grounded.

5. The LED lamp driving circuit according to claim 3, wherein: The first feedback module includes a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor and a thirteenth capacitor. One end of the fourteenth resistor, one end of the fifteenth resistor and one end of the thirteenth capacitor are commonly connected to the second output end of the first feedback module, the other end of the fourteenth resistor and one end of the sixteenth resistor are commonly connected to the input end of the first feedback module, the other end of the sixteenth resistor and one end of the seventeenth resistor are commonly connected to the first output end of the first feedback module, and the other end of the thirteenth capacitor, the other end of the fifteenth resistor and the other end of the seventeenth resistor are commonly connected to ground.

6. The LED lamp driving circuit according to any one of claims 1 to 5, characterized in that: The monitoring module includes a second filtering module, a third filtering module, a fourth filtering module, a second feedback module and a second operational amplifier. One end of the second filtering module is the first input end of the monitoring module, and the other end of the second filtering module is respectively connected to the inverting input end of the second operational amplifier and the output end of the second feedback module. One end of the third filtering module is the second input end of the monitoring module, and the other end of the third filtering module is connected to the non-inverting input end of the second operational amplifier. The output end of the second operational amplifier is respectively connected to the input end of the second feedback module and one end of the fourth filtering module. The other end of the fourth filtering module is the output end of the monitoring module.

7. The LED lamp driving circuit according to claim 6, wherein: The second filtering module includes a first resistor, a second resistor and a first capacitor, one end of the first resistor is one end of the second filtering module, the other end of the first resistor is respectively connected to one end of the first capacitor and one end of the second resistor, the other end of the second resistor is the other end of the second filtering module, and the other end of the first capacitor is grounded.

8. The LED lamp driving circuit according to claim 6, wherein: The third filtering module includes a third resistor, a fourth resistor, a fifth resistor and a second capacitor, one end of the third resistor is one end of the third filtering module, the other end of the third resistor is respectively connected to one end of the second capacitor and one end of the fourth resistor, the other end of the fourth resistor and one end of the fifth resistor are commonly connected to the other end of the third filtering module, the other end of the second capacitor is grounded, and the other end of the fifth resistor is grounded.

9. The LED lamp driving circuit according to claim 6, wherein: The second feedback module includes a sixth resistor and a third capacitor, one end of the sixth resistor and one end of the third capacitor are connected together as an input end of the second feedback module, and the other end of the sixth resistor and the other end of the third capacitor are connected together as an output end of the second feedback module; The fourth filtering module includes a seventh resistor, an eighth resistor and a fourth capacitor. One end of the seventh resistor and one end of the eighth resistor are connected together as one end of the fourth filtering module, the other end of the eighth resistor and one end of the fourth capacitor are connected together as the other end of the fourth filtering module, the other end of the fourth capacitor is grounded, and the other end of the seventh resistor is grounded.

10. A light therapy device, characterized in that: The light therapy device includes the LED lamp driving circuit according to any one of claims 1 to 9.

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