An LED light strip overcurrent and overvoltage protection device

Abstract

This invention discloses an overcurrent and overvoltage protection device for LED light strips, including an input power filter circuit, an overvoltage protection circuit, an overcurrent protection circuit, a main control MCU circuit, a PWM drive circuit, an RGBW four-channel power output circuit, a 3.3V auxiliary power supply circuit, and a 10V drive power supply circuit. The input power filter circuit is connected to a 12V DC input to provide a filtered and clean power supply for the entire device. This invention, by independently setting up dedicated sampling circuits for overvoltage and overcurrent protection, combined with high-precision voltage divider resistors and 3.3V Zener diode clamping protection, can accurately acquire voltage and current signals, effectively prevent peak voltage from damaging the MCU sampling pins, avoid protection false triggering and missed triggering problems, and improve protection reliability.

Description

Technical Field

[0001] This invention relates to the field of overcurrent and overvoltage protection technology, and in particular to an overcurrent and overvoltage protection device for LED light strips. Background Technology

[0002] LED strip lights, with their rich colors and flexible dimming capabilities, are widely used in decorative lighting, smart lighting, and other fields. Bluetooth wireless control LED strip light drivers have become mainstream due to their ease of operation. Overcurrent and overvoltage protection circuits, as the core component of such drivers, directly determine the stability of the device and the lifespan of the LED strip lights. They need to achieve real-time detection of input voltage and output current, and quickly shut down the power supply circuit in case of overvoltage or overcurrent, while also coordinating with PWM dimming circuits.

[0003] However, the mainstream overcurrent and overvoltage protection devices for LED strips currently on the market have the following drawbacks during use: they do not clamp the overvoltage and overcurrent sampling signals, which can easily damage the sampling pins of the main control MCU; the sampling resistors have low accuracy, which can easily lead to false triggering or failure to trigger the protection; the MCU's weak current signals directly drive the power transistors, resulting in insufficient driving capability and no freewheeling protection, leading to high power device loss; the input power supply lacks reliable reverse connection protection and wideband filtering design, resulting in large power supply noise and easy damage to devices due to reverse connection; the auxiliary power supply and drive power supply are not designed independently, resulting in large electromagnetic interference between modules; at the same time, the RGBW four-channel power output lacks separate channel filtering, which can easily cause brightness jitter and flickering during dimming. Overall, they are difficult to adapt to the stability and accuracy requirements of the smart lighting field. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies, such as "lack of clamping protection for overvoltage and overcurrent sampling signals, which easily damages the sampling pins of the main control MCU; low accuracy of sampling resistors, which easily leads to false triggering or non-triggering of protection; direct driving of power transistors by weak MCU signals, resulting in insufficient driving capability and lack of freewheeling protection, leading to high power device loss rate; lack of reliable reverse connection protection and wideband filtering design for input power supply, resulting in large power supply noise and easy burnout of devices due to reverse connection; lack of independent design for auxiliary power supply and drive power supply, resulting in large electromagnetic interference between modules; and lack of separate channel filtering for RGBW four-channel power output, which easily causes brightness jitter and flickering during dimming, making it difficult to meet the stability and accuracy requirements of the intelligent lighting field." Therefore, this invention proposes an overcurrent and overvoltage protection device for LED light strips.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An LED light strip overcurrent and overvoltage protection device includes: an input power supply filtering circuit, an overvoltage protection circuit, an overcurrent protection circuit, a main control MCU circuit, a PWM drive circuit, an RGBW four-channel power output circuit, a 3.3V auxiliary power supply circuit, and a 10V drive power supply circuit. The input power filtering circuit is connected to a 12V DC input to provide the whole machine with filtered and clean power supply. The overvoltage protection circuit and the overcurrent protection circuit respectively collect the input voltage and the power output circuit current and output the sampling signal to the main control MCU circuit; The main control MCU circuit receives the sampling signal and outputs the PWM control signal, and shuts down the PWM drive circuit when overvoltage or overcurrent is detected. The PWM drive circuit amplifies the PWM control signal and drives the RGBW four-channel power output circuit. The 3.3V auxiliary power supply circuit provides operating power to the main control MCU circuit, and the 10V drive power supply circuit provides operating power to the PWM drive circuit. The RGBW four-channel power output circuit is connected to the corresponding RGBW channels of the LED light strip to realize the power supply and dimming control of the LED light strip.

[0006] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the overvoltage protection circuit includes voltage divider resistors R31 and R32 and Zener diode DZ2, wherein DZ2 is a 3.3VSOD-123 type Zener diode; One end of R31 is connected to the 12V input positive terminal, and the other end is electrically connected to one end of R32, the cathode of DZ2, and the overvoltage sampling pin of the main control MCU circuit. The other end of R32 and the anode of DZ2 are both grounded, forming a resistor voltage divider sampling circuit. DZ2 provides 3.3V clamp protection for the overvoltage sampling signal.

[0007] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the overcurrent protection circuit includes sampling resistors RCS1, JR1, JR2 and Zener diode DZ4, wherein JR1 and JR2 are 1.5MR type sampling resistors and DZ4 is a 3.3VSOD-123 type Zener diode. JR1, JR2, and RCS1 are connected in series in the main power output circuit to collect the circuit current and form an overcurrent sampling signal. The cathode of DZ4 is connected to the overcurrent sampling signal output terminal, and the anode is grounded to clamp the overcurrent sampling signal at 3.3V. The overcurrent sampling signal output terminal is electrically connected to the overcurrent sampling pin of the main control MCU circuit.

[0008] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the main control MCU circuit includes a PHY6252-BLE Bluetooth MCU chip and a crystal oscillator circuit. The crystal oscillator circuit is an external clock circuit, including an XTL-16MSMD crystal oscillator and external starting capacitors XC1 and XC2. XC1 and XC2 are both 20pF / 25V 0603X7R type capacitors. The two ends of the XTL-16MSMD crystal oscillator are connected to the XTAL16M_O pin and the XTAL16M_I pin of the PHY6252-BLE Bluetooth MCU chip, respectively. One end of XC1 is connected to the XTAL16M_O pin and the other end is grounded. One end of XC2 is connected to the XTAL16M_I pin and the other end is grounded, forming a clock oscillation circuit. The RF pin of the PHY6252-BLE Bluetooth MCU chip is connected to the RF terminal to realize Bluetooth wireless control. Its overvoltage sampling pin and overcurrent sampling pin are electrically connected to the sampling signal output terminals of the overvoltage protection circuit and the overcurrent protection circuit, respectively. The PWM output pin outputs four PWM control signals: PWM-R, PWM-G, PWM-B, and PWM-W.

[0009] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the PWM driving circuit includes at least two EG27324SOP-8 type driving chips, and also includes current limiting resistors R19, R24, R29 and freewheeling diodes D2, D4, D5, wherein D2, D4, D5 are all 1N5819SOD-123 type diodes. The INA and INB pins of the EG27324 driver chip are electrically connected to the PWM control pins of the PHY6252-BLE Bluetooth MCU chip, respectively. Its VDD pin is connected to the output of the 10V drive power supply circuit, and its OCP pin is connected to the sampling signal output of the overcurrent protection circuit. The OUTA and OUTB pins are connected to the gates of the subsequent power transistors through current-limiting resistors. D2, D4, and D5 are connected in parallel between the power output of the EG27324 driver chip and ground to achieve freewheeling discharge.

[0010] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the RGBW four-channel power output circuit includes multiple NCE30150KTO-252 type MOSFETs, current limiting resistors R13, R18, R23, R28 and filter capacitors C13 and C14, wherein C13 and C14 are both 105 / 25V type capacitors; The MOSFETs are arranged in pairs, with upper and lower bridge arms. The drain of the upper bridge arm MOSFET is connected to the 12V input positive terminal, and its source is connected to the drain of the lower bridge arm MOSFET and led out to the corresponding RGBW channel of the LED light strip. The source of the lower bridge arm MOSFET is grounded. The gate of each MOSFET is electrically connected to the corresponding output terminal of the PWM drive circuit. The current limiting resistors R13, R18, R23, and R28 and the filter capacitors C13 and C14 are connected in parallel between the power supply terminal of each channel and ground to achieve filtering and noise reduction.

[0011] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the 3.3V auxiliary power supply circuit includes a voltage regulator chip U2A, filter capacitors C1A, C1B, EC2 and a voltage regulator diode DZ1, wherein C1A and C1B are both 22uF / 25V capacitors, EC2 is an electrolytic capacitor and DZ1 is a 3.3VSOD-123 voltage regulator diode; The VIN pin of U2A is connected to the 12V input positive terminal, the VOUT pin outputs a 3.3V working voltage, and the VSS pin is grounded; C1A, C1B, and EC2 are connected in parallel between the VOUT pin of U2A and ground, and DZ1 is connected in parallel between the 3.3V output terminal and ground, together realizing the stabilization and filtering of the 3.3V voltage.

[0012] As a preferred embodiment of the LED light strip overcurrent and overvoltage protection device of the present invention, the input power filtering circuit includes an electrolytic capacitor EC1, filter capacitors C1, C2, and C12, and reverse connection protection diodes D1, D1A, and D1B. EC1 is an electrolytic capacitor, C1 and C2 are 22uF / 25V capacitors, and C12 is a 10uF / 50V capacitor. The electrolytic capacitor EC1, filter capacitors C1, C2, and C12 are connected in parallel between the 12V input positive terminal and ground. The reverse connection protection diodes D1, D1A, and D1B are connected in series in the 12V input main circuit to achieve input power filtering and reverse connection protection. The 10V drive power supply circuit includes an energy storage inductor L1, feedback resistors R8 and R10. L1, R8, and R10 work together with the auxiliary power supply circuit to achieve a stable 10V voltage output through voltage division sampling.

[0013] Compared with the prior art, the beneficial effects of the present invention are: It features an independent overvoltage and overcurrent sampling circuit, coupled with high-precision voltage divider resistors and 3.3V Zener diode clamping protection. This not only accurately acquires voltage and current signals but also effectively prevents voltage spikes from damaging the MCU sampling pins, avoiding false triggering and missed triggering issues, thus improving protection reliability.

[0014] A dedicated PWM driver chip is added to amplify the control signal, and a freewheeling diode is used to discharge the reverse electromotive force, which solves the problem of insufficient drive of the low-voltage direct-drive power transistor, greatly reduces the loss and burnout risk of power devices such as MOSFETs, and extends the service life of the whole machine.

[0015] The input end integrates multi-stage filter capacitors and multi-tube series reverse connection protection circuit to achieve wideband power supply noise suppression and reliable reverse connection protection, avoid circuit failure caused by voltage fluctuations and power supply reverse connection, and improve the stability of input power supply.

[0016] By designing the 3.3V control power supply and 10V drive power supply separately, electromagnetic interference between modules is reduced; at the same time, the four RGBW outputs are equipped with independent RC filter circuits to effectively eliminate voltage noise, improve dimming jitter and flicker issues, and ensure uniform and stable color and brightness output.

[0017] It is equipped with an external high-precision crystal oscillator and an integrated Bluetooth master controller, which has high clock accuracy and stable wireless communication. It can realize four-channel PWM precise dimming control and adapt to the normal use needs of Bluetooth smart RGBW light strips. Attached Figure Description

[0018] Figure 1 This is an overall circuit diagram of an LED light strip overcurrent and overvoltage protection device proposed in this invention; Figure 2 This invention provides an auxiliary power supply circuit and a booster circuit diagram for an LED light strip overcurrent and overvoltage protection device. Figure 3 This invention provides a boost drive power supply circuit diagram for an LED light strip overcurrent and overvoltage protection device. Figure 4 This invention provides an overcurrent sampling circuit diagram for an LED light strip overcurrent and overvoltage protection device. Figure 5 This invention provides a B / R dual-channel PWM half-bridge drive and power output circuit diagram for an LED light strip overcurrent and overvoltage protection device. Figure 6 This invention provides a circuit diagram of a dual-channel PWM half-bridge drive and power output circuit for an LED light strip overcurrent and overvoltage protection device. Figure 7 This invention provides an overvoltage sampling protection circuit diagram for an LED light strip overcurrent and overvoltage protection device. Detailed Implementation

[0019] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0021] Reference Figures 1-7An LED light strip overcurrent and overvoltage protection device includes an input power filtering circuit, an overvoltage protection circuit, an overcurrent protection circuit, a main control MCU circuit, a PWM drive circuit, an RGBW four-channel power output circuit, a 3.3V auxiliary power supply circuit, and a 10V drive power supply circuit. The input power filtering circuit is connected to a 12V DC input to provide the whole machine with filtered and clean power. The overvoltage protection circuit and the overcurrent protection circuit respectively collect the input voltage and the power output circuit current and output the sampling signal to the main control MCU circuit; The main control MCU circuit receives the sampling signal and outputs the PWM control signal. When overvoltage or overcurrent is detected, the PWM drive circuit is turned off. The PWM drive circuit amplifies the PWM control signal and drives the RGBW four-channel power output circuit; The 3.3V auxiliary power supply circuit provides operating power to the main control MCU circuit, and the 10V drive power supply circuit provides operating power to the PWM drive circuit. The RGBW four-channel power output circuit is connected to the corresponding RGBW channels of the LED light strip to realize the power supply and dimming control of the LED light strip; Each module adopts an independent power supply circuit and signal transmission circuit design to avoid electromagnetic interference and fault transmission between modules. At the same time, the interfaces of each module adopt a standardized design to adapt to the four independent power supply and dimming requirements of RGBWLED light strips, realizing integrated and coordinated control of protection functions and drive dimming functions.

[0022] In this circuit, considering that directly sampling the 12V input voltage during overvoltage sampling would exceed the 3.3V withstand voltage threshold of the main control MCU, and that the sampling signal is prone to voltage spikes, potentially causing damage to the MCU sampling pins, and that low accuracy of the voltage divider resistors would cause sampling ratio deviations, leading to false triggering or failure to trigger the protection, the overvoltage protection circuit includes voltage divider resistors R31 and R32 and a Zener diode DZ2. DZ2 is a 3.3VSOD-123 type Zener diode. One end of R31 is connected to the positive terminal of the 12V input, and the other end is connected to one end of R32. The overvoltage sampling pin of the main control MCU circuit is electrically connected to the cathode of DZ2 and the other end of R32. The anode of DZ2 is grounded, forming a resistor voltage divider sampling circuit. DZ2 provides 3.3V clamp protection for the overvoltage sampling signal. R31 and R32 are high-precision surface mount resistors to ensure the accuracy of the voltage division ratio and stably convert the 12V input voltage into a sampling voltage suitable for the MCU. At the same time, the DZ2 surface mount Zener diode is small in size and has a fast response speed, which can achieve voltage clamping in microseconds, effectively avoiding damage to the MCU by peak voltage.

[0023] Furthermore, considering that the high current sampling of the power output circuit requires low-resistance, high-precision sampling resistors, and that voltage spikes in the sampling signal can damage the sampling pins of the main control MCU, and that the total current of the multi-channel power output needs to be uniformly sampled in the main circuit to achieve overcurrent protection for all channels, the overcurrent protection circuit includes sampling resistors RCS1, JR1, JR2 and Zener diode DZ4. JR1 and JR2 are 1.5MR type sampling resistors, and DZ4 is a 3.3VSOD-123 type Zener diode. JR1, JR2, and RCS1 are connected in series in the main power output circuit to collect the circuit current and form an overcurrent sampling signal. The cathode of DZ4 is connected to the overcurrent sampling signal output terminal, and the anode is grounded to clamp the overcurrent sampling signal at 3.3V. The overcurrent sampling signal output terminal is electrically connected to the overcurrent sampling pin of the main control MCU circuit.

[0024] Furthermore, considering that the main control MCU requires a stable high-frequency clock signal to ensure the accurate execution of calculation and control instructions, and that Bluetooth wireless control requires an external crystal oscillator circuit to achieve a precise radio frequency, and that the absence of an independent start-up capacitor would cause the crystal oscillator to fail to start properly, resulting in the MCU failing to work, the main control MCU circuit includes a PHY6252-BLE Bluetooth MCU chip and a crystal oscillator circuit. The crystal oscillator circuit is an external clock circuit, including an XTL-16MSMD crystal oscillator and external start-up capacitors XC1 and XC2. Both XC1 and XC2 are 20pF / 25V0603X7R type capacitors. The two ends of the XTL-16MSMD crystal oscillator are connected to the XTAL16M_O pin and the XTAL16M_I pin of the PHY6252-BLE Bluetooth MCU chip, respectively. One end of XC1 is connected to the XTAL16M_O pin and the other end is grounded. One end of XC2 is connected to the XTAL16M_I pin and the other end is grounded, forming a clock oscillation circuit. The PHY6252-BLE Bluetooth MCU chip's RF pins are connected to the RF terminal to achieve Bluetooth wireless control. Its overvoltage sampling pin and overcurrent sampling pin are electrically connected to the sampling signal output terminals of the overvoltage protection circuit and overcurrent protection circuit, respectively. The PWM output pin outputs four PWM control signals: PWM-R, PWM-G, PWM-B, and PWM-W.

[0025] Furthermore, considering that the PWM control signal output by the main control MCU is a weak signal with insufficient driving capability, it cannot directly drive high-power MOSFETs. Additionally, the power transistors generate a back electromotive force during switching, which can easily damage the driver chip and the power transistors. Moreover, the software-level overcurrent protection has a slow response speed, failing to provide rapid protection for power devices. Therefore, the PWM drive circuit includes at least two EG27324SOP-8 type driver chips, as well as current-limiting resistors R19, R24, R29 and freewheeling diodes D2, D4, D5. D2, D4, and D5 are all 1N5819SOD-123 type diodes. The INA and IN terminals of the EG27324 driver chip... Pin B is electrically connected to the PWM control pin of the PHY6252-BLE Bluetooth MCU chip. Its VDD pin is connected to the output of the 10V drive power supply circuit, and its OCP pin is connected to the sampling signal output of the overcurrent protection circuit. Pins OUTA and OUTB are connected to the gate of the subsequent power transistors through current-limiting resistors. D2, D4, and D5 are connected in parallel between the power output of the EG27324 driver chip and ground to achieve freewheeling discharge. A single chip can drive the upper and lower power transistors of one bridge arm, and two chips can achieve RGBW four-channel drive. Its built-in overcurrent protection module can directly receive the overcurrent sampling signal through the OCP pin to realize the hardware fast overcurrent shutdown of the driver stage. Furthermore, considering that the RGBW LED light strip requires four independent power supplies and dimming controls, high-power MOSFETs will generate voltage noise during switching, affecting the smoothness of dimming. In addition, the voltage and current withstand capabilities of ordinary power transistors are insufficient and cannot meet the power supply requirements of high-power LED light strips. Therefore, the RGBW four-way power output circuit includes multiple NCE30150KTO-252 type MOSFETs, current limiting resistors R13, R18, R23, R28 and filter capacitors C13 and C14. C13 and C14 are both 105 / 25V type capacitors. The MOSFETs are arranged in pairs, with upper and lower bridge arms. The drain of the upper bridge arm MOSFET is connected to the 12V input positive terminal, and its source is connected to the drain of the lower bridge arm MOSFET and led out to the corresponding RGBW channel of the LED light strip. The source of the lower bridge arm MOSFET is grounded. The gate of each MOSFET is electrically connected to the corresponding output terminal of the PWM drive circuit. Current limiting resistors R13, R18, R23, and R28 and filter capacitors C13 and C14 are connected in parallel between the power supply terminal of each channel and ground to achieve filtering and noise reduction.

[0026] Furthermore, considering that the main control MCU operates at 3.3V, a separate voltage regulator circuit is needed to convert the 12V input voltage to a stable 3.3V low voltage. A single capacitor filter cannot simultaneously filter out high-frequency and low-frequency noise; large voltage fluctuations and ripple can cause MCU calculation errors and control command failures. Therefore, the 3.3V auxiliary power supply circuit includes a voltage regulator chip U2A, filter capacitors C1A, C1B, and EC2, and a Zener diode DZ1. C1A and C1B are both 22uF / 25V capacitors, EC2 is an electrolytic capacitor, and DZ1 is a 3.3VSOD-123 Zener diode. The VIN pin of U2A is connected to the positive terminal of the 12V input, the VOUT pin outputs the 3.3V operating voltage, and the VSS pin is grounded. C1A, C1B, and EC2 are connected in parallel between the VOUT pin of U2A and ground, and DZ1 is connected in parallel between the 3.3V output terminal and ground, jointly achieving voltage regulation and filtering of the 3.3V voltage. Furthermore, considering that the 12V input power supply has problems such as grid noise and voltage fluctuations, which will affect the working stability of each module of the whole machine, and that reverse connection of the power supply will directly burn out the active components in the circuit, causing the whole machine to be scrapped, and that the PWM drive chip requires an independent 10V drive voltage, conventional step-down circuits do not have high-precision feedback sampling, which will lead to a large deviation of the 10V output voltage and affect the working performance of the drive chip, the input power filter circuit includes an electrolytic capacitor EC1, filter capacitors C1, C2, C12 and reverse connection protection diodes D1, D1A, D1B. EC1 is an electrolytic capacitor, C1 and C2 are 22uF / 25V type capacitors, and C12 is a 10uF / 50V type capacitor. The electrolytic capacitor EC1, filter capacitors C1, C2, C12 are connected in parallel between the 12V input positive terminal and ground, and the reverse connection protection diodes D1, D1A, D1B are connected in series in the 12V input main circuit to achieve input power filtering and reverse connection protection. The 10V drive power supply circuit includes an energy storage inductor L1, feedback resistors R8 and R10. L1, R8, and R10 work together with the auxiliary power supply circuit to achieve a stable 10V voltage output through voltage division sampling.

[0027] It is worth noting that the entire device is controlled by a controller. Since the controller is a common device and belongs to the mature technology, its electrical connection relationship and specific circuit structure will not be described in detail here.

[0028] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the technical scope disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention. In the description of the present invention, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," or "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

Claims

1. An overcurrent and overvoltage protection device for LED light strips, characterized in that, include: Input power filtering circuit, overvoltage protection circuit, overcurrent protection circuit, main control MCU circuit, PWM drive circuit, RGBW four-channel power output circuit, 3.3V auxiliary power supply circuit and 10V drive power supply circuit; The input power filtering circuit is connected to a 12V DC input to provide the whole machine with filtered and clean power supply. The overvoltage protection circuit and the overcurrent protection circuit respectively collect the input voltage and the power output circuit current and output the sampling signal to the main control MCU circuit; The main control MCU circuit receives the sampling signal and outputs the PWM control signal, and shuts down the PWM drive circuit when overvoltage or overcurrent is detected. The PWM drive circuit amplifies the PWM control signal and drives the RGBW four-channel power output circuit. The 3.3V auxiliary power supply circuit provides operating power to the main control MCU circuit, and the 10V drive power supply circuit provides operating power to the PWM drive circuit. The RGBW four-channel power output circuit is connected to the corresponding RGBW channels of the LED light strip to realize the power supply and dimming control of the LED light strip.

2. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The overvoltage protection circuit includes voltage divider resistors R31 and R32 and a Zener diode DZ2, wherein DZ2 is a 3.3VSOD-123 type Zener diode; One end of R31 is connected to the 12V input positive terminal, and the other end is electrically connected to one end of R32, the cathode of DZ2, and the overvoltage sampling pin of the main control MCU circuit. The other end of R32 and the anode of DZ2 are both grounded, forming a resistor voltage divider sampling circuit. DZ2 provides 3.3V clamp protection for the overvoltage sampling signal.

3. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The overcurrent protection circuit includes sampling resistors RCS1, JR1, JR2 and Zener diode DZ4, wherein JR1 and JR2 are 1.5MR type sampling resistors and DZ4 is a 3.3VSOD-123 type Zener diode. JR1, JR2, and RCS1 are connected in series in the main power output circuit to collect the circuit current and form an overcurrent sampling signal. The cathode of DZ4 is connected to the overcurrent sampling signal output terminal, and the anode is grounded to clamp the overcurrent sampling signal at 3.3V. The overcurrent sampling signal output terminal is electrically connected to the overcurrent sampling pin of the main control MCU circuit.

4. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The main control MCU circuit includes a PHY6252-BLE Bluetooth MCU chip and a crystal oscillator circuit. The crystal oscillator circuit is an external clock circuit, including an XTL-16MSMD crystal oscillator and external starting capacitors XC1 and XC2. XC1 and XC2 are both 20pF / 25V0603X7R type capacitors. The two ends of the XTL-16MSMD crystal oscillator are connected to the XTAL16M_O pin and the XTAL16M_I pin of the PHY6252-BLE Bluetooth MCU chip, respectively. One end of XC1 is connected to the XTAL16M_O pin and the other end is grounded. One end of XC2 is connected to the XTAL16M_I pin and the other end is grounded, forming a clock oscillation circuit. The RF pin of the PHY6252-BLE Bluetooth MCU chip is connected to the RF terminal to realize Bluetooth wireless control. Its overvoltage sampling pin and overcurrent sampling pin are electrically connected to the sampling signal output terminals of the overvoltage protection circuit and the overcurrent protection circuit, respectively. The PWM output pin outputs four PWM control signals: PWM-R, PWM-G, PWM-B, and PWM-W.

5. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The PWM drive circuit includes at least two EG27324SOP-8 type drive chips, as well as current limiting resistors R19, R24, R29 and freewheeling diodes D2, D4, D5, wherein D2, D4, D5 are all 1N5819SOD-123 type diodes. The INA and INB pins of the EG27324 driver chip are electrically connected to the PWM control pins of the PHY6252-BLE Bluetooth MCU chip, respectively. Its VDD pin is connected to the output of the 10V drive power supply circuit, and its OCP pin is connected to the sampling signal output of the overcurrent protection circuit. The OUTA and OUTB pins are connected to the gates of the subsequent power transistors through current-limiting resistors. D2, D4, and D5 are connected in parallel between the power output of the EG27324 driver chip and ground to achieve freewheeling discharge.

6. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The RGBW four-channel power output circuit includes multiple NCE30150KTO-252 type MOSFETs, current limiting resistors R13, R18, R23, R28 and filter capacitors C13 and C14, wherein C13 and C14 are both 105 / 25V type capacitors; The MOSFETs are arranged in pairs, with upper and lower bridge arms. The drain of the upper bridge arm MOSFET is connected to the 12V input positive terminal, and its source is connected to the drain of the lower bridge arm MOSFET and led out to the corresponding RGBW channel of the LED light strip. The source of the lower bridge arm MOSFET is grounded. The gate of each MOSFET is electrically connected to the corresponding output terminal of the PWM drive circuit. The current limiting resistors R13, R18, R23, and R28 and the filter capacitors C13 and C14 are connected in parallel between the power supply terminal of each channel and ground to achieve filtering and noise reduction.

7. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The 3.3V auxiliary power supply circuit includes a voltage regulator chip U2A, filter capacitors C1A, C1B, EC2 and a Zener diode DZ1. C1A and C1B are both 22uF / 25V capacitors, EC2 is an electrolytic capacitor and DZ1 is a 3.3VSOD-123 Zener diode. The VIN pin of U2A is connected to the 12V input positive terminal, the VOUT pin outputs a 3.3V working voltage, and the VSS pin is grounded; C1A, C1B, and EC2 are connected in parallel between the VOUT pin of U2A and ground, and DZ1 is connected in parallel between the 3.3V output terminal and ground, together realizing the stabilization and filtering of the 3.3V voltage.

8. The LED light strip overcurrent and overvoltage protection device according to claim 1, characterized in that: The input power filtering circuit includes an electrolytic capacitor EC1, filter capacitors C1, C2, and C12, and reverse connection protection diodes D1, D1A, and D1B. EC1 is an electrolytic capacitor, C1 and C2 are 22uF / 25V capacitors, and C12 is a 10uF / 50V capacitor. The electrolytic capacitor EC1, filter capacitors C1, C2, and C12 are connected in parallel between the 12V input positive terminal and ground. The reverse connection protection diodes D1, D1A, and D1B are connected in series in the 12V input main circuit to achieve input power filtering and reverse connection protection. The 10V drive power supply circuit includes an energy storage inductor L1, feedback resistors R8 and R10. L1, R8, and R10 work together with the auxiliary power supply circuit to achieve a stable 10V voltage output through voltage division sampling.

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