Multi-mode backlight control circuit based on touch sensing

Abstract

The utility model relates to the technical field of lighting or switch control improvement, in particular to a multi-mode backlight lamp control circuit based on touch sensing, which comprises the following steps: after a power supply is input, supplying power to a touch sensing circuit, an LED (light-emitting diode) driving circuit and a side light-emitting lamp circuit through a power supply and a communication circuit; data exchange between the touch sensing circuit and the range hood system is completed; after a touch signal is collected by the touch sensing circuit, a control command is transmitted to the range hood system and the LED driving circuit; after the range hood system receives the control command, the function of the range hood is controlled according to the control command; and after receiving the control command, the LED driving circuit completes on-off control of the side light-emitting lamp circuit according to the control command. According to the utility model, the touch PAD is designed and integrated on the touch chip U1, the response speed is fast, the occupied area is small, the cost is low, and the service life is long.

Description

Technical Field

[0001] This utility model relates to the field of lighting or switch control improvement technology, specifically a multi-mode backlight control circuit based on touch sensing. Background Technology

[0002] Currently, push-button switches are often added to lighting or switch control products for operation. These products are characterized by their simple structure, ease of understanding and use, but their mechanical design limits their lifespan. Furthermore, mechanical wear over time leads to increased failure rates and higher maintenance costs for users. To extend the lifespan of push-button switches, the industry common practice is to optimize the selection of button materials, such as using wear-resistant materials for button caps or improving the internal structure to reduce friction between moving parts. However, while these measures alleviate the problem to some extent, they do not fundamentally solve it, and the improved buttons still suffer from issues such as slow response and poor tactile feedback. Summary of the Invention

[0003] The purpose of this invention is to provide a multi-mode backlight control circuit based on touch sensing to solve the problems mentioned in the prior art.

[0004] To achieve the above objectives, this utility model provides the following technical solution: a multi-mode backlight control circuit based on touch sensing, the circuit comprising:

[0005] After power input, the power supply and communication circuit supplies power to the touch sensing circuit, LED driver circuit, and side-emitting lamp circuit. The power supply and communication circuit consists of connector CN1, TVS diode D1, capacitors C1, C2, C3, C4, C7, C8, electrolytic capacitor EC1, voltage divider resistors R1 and R2, current limiting resistors R3 and R4, rectifier diodes D2 and D3, power supply VCC_5V, and power supply VCC_12V; and completes data exchange between the touch sensing circuit and the range hood system.

[0006] The touch sensing circuit consists of connector P1, touch chip U1, touch sensors TK1, TK2, TK3, TK4, and TK5, capacitors C10 and C11, resistors R14, R15, R16, R18, R20, R26, and R27, LED driver chip U2, LED1 at touch sensor TK1, LED2 at touch sensor TK2, LED3 at touch sensor TK3, LED4 at touch sensor TK4, LED5 at touch sensor TK5, and power supply VCC_5V. After the touch sensing circuit collects the touch signal, it transmits the control command to the range hood system and the LED driver circuit. After receiving the control command, the range hood system controls the range hood's lighting function, constant suction function, low fan speed function, high fan speed function, and on / off function according to the control command.

[0007] The LED driving circuit consists of an LED driver chip U2, resistors R30 and R31, capacitors C12 and C13, and a power supply VCC_5V. Resistors R30, R31, C12, and C13 are connected in parallel to the LED driver chip U2. The side-emitting lamp circuit includes an LED array; 40 side-emitting lamps are connected in parallel to form the LED array and are then connected to the LED driver chip U2. This parallel connection means that each lamp has its own independent path to the power supply, allowing each lamp to be controlled independently. If one lamp malfunctions, it will not affect the operation of the other lamps. When the LED driver chip U2 receives an IIC signal from the touch chip U1, it controls the LED array to turn on and off according to the signal. After receiving a control command, the LED driver circuit controls the switching of the side-emitting lamp circuit accordingly.

[0008] According to the above scheme, connector CN1 includes 8 pins, namely pins 1, 2, 3, 4, 5, 6, 7, and 8; pin 1 of connector CN1 is connected to power supply VCC_12V; pin 2 of connector CN1 is connected to ground; pin 3 of connector CN1 is connected to TXD in series with current-limiting resistor R3; pin 4 of connector CN1 is connected to RXD in series with current-limiting resistor R4; pin 5 of connector CN1 is connected in parallel with electrolytic capacitor EC1, with one end connected to power supply VCC_5V and the other end connected to ground; pins 6, 7, and 8 of connector CN1 are connected to ground; TXD represents the communication interface for transmitting data, and RXD represents the communication interface for receiving data.

[0009] The anode of rectifier diode D2 is connected to RXD, and the cathode is connected to ground; the anode of rectifier diode D3 is connected to TXD, and the cathode is connected to ground; capacitors C7 and C8 are connected in parallel, with one end connected to TXD and the other end connected to ground; capacitors C8 and C7 are connected in parallel, with one end connected to RXD and the other end connected to ground; voltage divider resistors R1 and R2 are connected in parallel, with one end connected to TXD and the other end connected to power supply VCC_5V; voltage divider resistors R2 and R1 are connected in parallel, with one end connected to RXD and the other end connected to power supply VCC_5V.

[0010] The capacitors C1, C2, C3, C4 and TVS diode D1 are connected in parallel. After the TVS diode D1 is connected in parallel with capacitors C1, C2, C3 and C4, the anode is connected to the power supply VCC_5V and the cathode is connected to the ground wire.

[0011] According to the above scheme, the power supply and communication circuit includes a power supply circuit and a communication circuit;

[0012] The power supply circuit, after receiving the power supply, uses a TVS diode D1 for transient voltage suppression to prevent damage to subsequent circuits from instantaneous high voltage. Electrolytic capacitors EC1, C1, C2, C3, and C4 are used for filtering to eliminate high-frequency noise and obtain a stable DC voltage to supply power to the power supply and communication circuits. The power supply is then filtered by capacitors C7 and C8 before supplying power to the touch sensing circuit, LED driver circuit, and side-emitting lamp circuit.

[0013] The communication circuit, after receiving power, generates a stable voltage through voltage divider resistors R1 and R2; TXD, after adjusting the voltage through rectifier diode D2, transmits visible light to indicate the data transmission status; RXD, after adjusting the voltage through rectifier diode D3, uses resistors R3 and R4 to complete the detection signal and protection circuit.

[0014] According to the above scheme, the connector P1 includes 4 pins, namely pins 1, 2, 3 and 4;

[0015] Pin 1 of connector P1 is connected to power supply VCC_5V; pin 2 of connector P1 is connected to touch chip U1; pin 3 of connector P1 is connected to touch chip U1; pin 4 of connector P1 is connected to ground.

[0016] The capacitors C10 and C11 are connected in parallel with the touch chip U1, with one end connected to the power supply VCC_5V and the other end connected to the ground wire; one end of the resistor R26 is connected in series with the touch chip U1 and the other end is connected in series with the LED driver chip U2; one end of the resistor R27 is connected in series with the touch chip U1 and the other end is connected in series with the LED driver chip U2; the touch sensor TK1 is connected to the touch chip U1 after being connected in series with the resistor R14; the touch sensor TK2 is connected to the touch chip U1 after being connected in series with the resistor R15; the touch sensor TK3 is connected to the touch chip U1 after being connected in series with the resistor R16; the touch sensor TK4 is connected to the touch chip U1 after being connected in series with the resistor R18; the touch sensor TK5 is connected to the touch chip U1 after being connected in series with the resistor R20; the indicator lights LED1 at touch sensor TK1, LED2 at touch sensor TK2, LED3 at touch sensor TK3, LED4 at touch sensor TK4, and LED5 at touch sensor TK5 are connected to the touch chip U1.

[0017] According to the above scheme, the touch sensor TK5 and the resistor R20 are combined to form an RC network. When the touch sensor TK5 collects the touch signal, it generates a change in the level signal. After the touch chip U1 senses the change in the level signal from the touch sensor TK5, it makes the display light LED5 at the touch sensor TK5 turn on and sends an IIC signal to the LED driver chip and a UART signal to the range hood system.

[0018] After receiving the signal, the LED driver chip controls the light display of the side-emitting lamp circuit; after receiving the signal, the range hood system starts.

[0019] When the range hood system is started, the touch sensor TK1 collects the touch signal. The touch sensor TK1 and the resistor R14 combine to form an RC network to generate a change in the level signal. The touch chip U1 senses the change in the level signal, causing the indicator LED1 at the touch sensor TK1 to become constantly lit. It also sends a UART signal to the range hood system. After receiving the signal, the range hood system starts the range hood lighting function.

[0020] When the LED1 indicator light at the touch sensor TK1 is constantly on and the range hood lighting function is turned on, the touch sensor TK1 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal, it causes the LED1 indicator light at the touch sensor TK1 to change from a constantly on state to a flashing state, and sends a UART signal to the range hood system to turn off the range hood lighting function.

[0021] When the LED1 indicator light at the touch sensor TK1 is flashing and the range hood lighting function is off, the touch sensor TK1 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal, it causes the LED1 indicator light at the touch sensor TK1 to change from flashing to constant light and sends a UART signal to the range hood system to turn on the range hood lighting function.

[0022] When the LED1 indicator light at the touch sensor TK1 is flashing and the range hood lighting function is off, if the touch sensor TK1 does not collect a touch signal within 30 seconds and the touch chip U1 does not sense a change in the level signal, the LED1 indicator light at the touch sensor TK1 will change from flashing to breathing and send a UART signal to the range hood system to keep the range hood lighting function off.

[0023] The process of touch sensors TK2, TK3 and TK4 acquiring touch signals is the same as that of touch sensor TK1.

[0024] After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK2 and resistor R15, it controls the change of the display light LED2 at touch sensor TK2 and sends a UART signal to the range hood system to control the opening and closing of the constant suction function of the range hood.

[0025] After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK3 and resistor R16, it controls the change of the display light LED3 at touch sensor TK3 and sends a UART signal to the range hood system to control the opening and closing of the range hood's low-power function.

[0026] After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK4 and resistor R18, it controls the change of the display light LED4 at touch sensor TK4 and sends a UART signal to the range hood system to control the opening and closing of the range hood's high-power function.

[0027] When the range hood system is started, the touch sensor TK5 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal from the touch sensor TK5, it causes the indicator LED5 at the touch sensor TK5 to change from a constantly lit state to a turned-off state, and sends an IIC signal to the LED driver chip and a UART signal to the range hood system. After receiving the signal, the LED driver chip controls the side-emitting lamp circuit to turn off the light. After receiving the signal, the range hood system turns off.

[0028] Compared with the prior art, the beneficial effects of this utility model are:

[0029] 1. This utility model has a long service life, occupies a small area, and has a wide range of applications;

[0030] 2. This utility model uses a side-emitting lamp, which makes the brightness of the touch display area uniform and the display effect better;

[0031] 3. This utility model integrates the touch PAD design onto the touch chip U1, resulting in fast response speed, low cost, and long lifespan. Attached Figure Description

[0032] Figure 1 This is a flowchart of a multi-mode backlight control circuit based on touch sensing according to this utility model;

[0033] Figure 2 This is a schematic diagram of the power supply and communication circuit of a multi-mode backlight control circuit based on touch sensing according to this utility model.

[0034] Figure 3 This is a schematic diagram of a touch sensing circuit for a multi-mode backlight control circuit based on touch sensing according to this utility model.

[0035] Figure 4 This is a schematic diagram of an LED driver circuit for a multi-mode backlight control circuit based on touch sensing, according to this utility model. Detailed Implementation

[0036] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0037] like Figures 1-4 As shown in the embodiment of this utility model, a multi-mode backlight control circuit based on touch sensing is provided. The circuit includes a power supply and communication circuit, an LED driving circuit, a touch sensing circuit, a side-emitting lamp circuit, and a range hood system.

[0038] After power input, the power supply and communication circuit supplies power to the touch sensing circuit, LED driver circuit, and side-emitting lamp circuit. The power supply and communication circuit consists of connector CN1, TVS diode D1, capacitors C1, C2, C3, C4, C7, C8, electrolytic capacitor EC1, voltage divider resistors R1 and R2, current limiting resistors R3 and R4, rectifier diodes D2 and D3, power supply VCC_5V, and power supply VCC_12V; and completes data exchange between the touch sensing circuit and the range hood system.

[0039] The touch sensing circuit consists of connector P1, touch chip U1, touch sensors TK1, TK2, TK3, TK4, and TK5, capacitors C10 and C11, resistors R14, R15, R16, R18, R20, R26, and R27, LED driver chip U2, LED1 at touch sensor TK1, LED2 at touch sensor TK2, LED3 at touch sensor TK3, LED4 at touch sensor TK4, LED5 at touch sensor TK5, and power supply VCC_5V. After the touch sensing circuit collects the touch signal, it transmits the control command to the range hood system and the LED driver circuit. After receiving the control command, the range hood system controls the range hood's lighting function, constant suction function, low fan speed function, high fan speed function, and on / off function according to the control command.

[0040] The LED driving circuit consists of an LED driver chip U2, resistors R30 and R31, capacitors C12 and C13, and a power supply VCC_5V. Resistors R30, R31, C12, and C13 are connected in parallel to the LED driver chip U2. The side-emitting lamp circuit includes an LED array; 40 side-emitting lamps are connected in parallel to form an LED array and are connected to the LED driver chip U2. When the LED driver chip U2 receives an IIC signal from the touch chip U1, it controls the LED array to turn on and off according to the signal. After receiving a control command, the LED driver circuit controls the switching of the side-emitting lamp circuit accordingly.

[0041] The connector CN1 includes 8 pins, designated as pins 1, 2, 3, 4, 5, 6, 7, and 8. Pin 1 of connector CN1 is connected to the power supply VCC_12V; pin 2 of connector CN1 is connected to ground; pin 3 of connector CN1 is connected in series with current-limiting resistor R3 and then connected to TXD; pin 4 of connector CN1 is connected in series with current-limiting resistor R4 and then connected to RXD; pin 5 of connector CN1 is connected in parallel with electrolytic capacitor EC1, with one end connected to the power supply VCC_5V and the other end connected to ground; pins 6, 7, and 8 of connector CN1 are connected to ground; TXD represents the communication interface for transmitting data, and RXD represents the communication interface for receiving data.

[0042] The anode of rectifier diode D2 is connected to RXD, and the cathode is connected to ground; the anode of rectifier diode D3 is connected to TXD, and the cathode is connected to ground; capacitors C7 and C8 are connected in parallel, with one end connected to TXD and the other end connected to ground; capacitors C8 and C7 are connected in parallel, with one end connected to RXD and the other end connected to ground; voltage divider resistors R1 and R2 are connected in parallel, with one end connected to TXD and the other end connected to power supply VCC_5V; voltage divider resistors R2 and R1 are connected in parallel, with one end connected to RXD and the other end connected to power supply VCC_5V.

[0043] The capacitors C1, C2, C3, C4 and TVS diode D1 are connected in parallel. After the TVS diode D1 is connected in parallel with capacitors C1, C2, C3 and C4, the anode is connected to the power supply VCC_5V and the cathode is connected to the ground wire.

[0044] The connector P1 includes four pins, namely pins 1, 2, 3 and 4.

[0045] Pin 1 of connector P1 is connected to power supply VCC_5V; pin 2 of connector P1 is connected to touch chip U1; pin 3 of connector P1 is connected to touch chip U1; pin 4 of connector P1 is connected to ground.

[0046] The capacitors C10 and C11 are connected in parallel with the touch chip U1, with one end connected to the power supply VCC_5V and the other end connected to the ground wire; one end of the resistor R26 is connected in series with the touch chip U1 and the other end is connected in series with the LED driver chip U2; one end of the resistor R27 is connected in series with the touch chip U1 and the other end is connected in series with the LED driver chip U2; the touch sensor TK1 is connected to the touch chip U1 after being connected in series with the resistor R14; the touch sensor TK2 is connected to the touch chip U1 after being connected in series with the resistor R15; the touch sensor TK3 is connected to the touch chip U1 after being connected in series with the resistor R16; the touch sensor TK4 is connected to the touch chip U1 after being connected in series with the resistor R18; the touch sensor TK5 is connected to the touch chip U1 after being connected in series with the resistor R20; the indicator lights LED1 at touch sensor TK1, LED2 at touch sensor TK2, LED3 at touch sensor TK3, LED4 at touch sensor TK4, and LED5 at touch sensor TK5 are connected to the touch chip U1.

[0047] The working principle of this utility model is: a multi-mode backlight control circuit based on touch sensing, the method comprising:

[0048] After the input power is applied, transient voltage is suppressed by TVS diode D1. Transient voltage suppression by TVS diode D1 prevents damage to subsequent circuits caused by instantaneous high voltage. Electrolytic capacitors EC1, C1, C2, C3, and C4 are used for filtering to eliminate high-frequency noise and obtain a stable DC voltage to supply power to the power supply and communication circuit. The power supply is then filtered by capacitors C7 and C8 before supplying power to the touch sensing circuit, LED driver circuit, and side-emitting lamp circuit.

[0049] After the input power is applied, the voltage is divided by voltage divider resistors R1 and R2 to generate a stable voltage. TXD, after adjusting the voltage through rectifier diode D2, transmits visible light to indicate the data transmission status. RXD, after adjusting the voltage through rectifier diode D3, uses resistors R3 and R4 to complete the detection signal and protection circuit.

[0050] Touch sensor TK5 and resistor R20 are combined to form an RC network. When touch sensor TK5 collects a touch signal, it generates a change in the level signal. After the touch chip U1 senses the change in the level signal from touch sensor TK5, it makes the indicator LED5 at touch sensor TK5 turn on and sends an IIC signal to the LED driver chip and a UART signal to the range hood system.

[0051] After receiving the signal, the LED driver chip controls the light display of the side light-emitting circuit; after receiving the signal, the range hood system starts.

[0052] When the range hood system is started, the touch sensor TK1 collects the touch signal. The touch sensor TK1 and the resistor R14 combine to form an RC network to generate a change in the level signal. The touch chip U1 senses the change in the level signal, causing the indicator LED1 at the touch sensor TK1 to become constantly lit. It also sends a UART signal to the range hood system. After receiving the signal, the range hood system starts the range hood lighting function.

[0053] When the LED1 indicator light at the touch sensor TK1 is constantly on and the range hood lighting function is turned on, the touch sensor TK1 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal, it causes the LED1 indicator light at the touch sensor TK1 to change from a constantly on state to a flashing state, and sends a UART signal to the range hood system to turn off the range hood lighting function.

[0054] When the LED1 indicator light at the touch sensor TK1 is flashing and the range hood lighting function is off, the touch sensor TK1 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal, it causes the LED1 indicator light at the touch sensor TK1 to change from flashing to constant light and sends a UART signal to the range hood system to turn on the range hood lighting function.

[0055] When the LED1 indicator light at the touch sensor TK1 is flashing and the range hood lighting function is off, if the touch sensor TK1 does not collect a touch signal within 30 seconds, the touch chip U1 does not sense a change in the level signal, causing the LED1 indicator light at the touch sensor TK1 to change from flashing to breathing mode, and sends a UART signal to the range hood system to keep the range hood lighting function off.

[0056] The process for touch sensors TK2, TK3, and TK4 to acquire touch signals is the same as that for touch sensor TK1.

[0057] After the touch chip U1 senses the change in the level signal generated by the RC network formed by the touch sensor TK2 and the resistor R15, it controls the change of the indicator LED2 at the touch sensor TK2 and sends a UART signal to the range hood system to control the opening and closing of the constant suction function of the range hood.

[0058] After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK3 and resistor R16, it controls the change of the display light LED3 at touch sensor TK3 and sends a UART signal to the range hood system to control the opening and closing of the range hood's low-power function.

[0059] After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK4 and resistor R18, it controls the change of the display light LED4 at touch sensor TK4 and sends a UART signal to the range hood system to control the opening and closing of the range hood's high-power function.

[0060] When the range hood system is started, the touch sensor TK5 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal from the touch sensor TK5, it causes the indicator LED5 at the touch sensor TK5 to change from a constantly lit state to a turned-off state, and sends an IIC signal to the LED driver chip and a UART signal to the range hood system. After receiving the signal, the LED driver chip controls the light circuit on the LED driver side to turn off the light. After receiving the signal, the range hood system turns off.

[0061] When the LED driver chip U2 receives the IIC signal sent by the touch chip U1, it controls the LED array to turn on and off according to the signal.

[0062] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A multi-mode backlight control circuit based on touch sensing, characterized in that, The circuit includes: After power input, the power supply and communication circuit supplies power to the touch sensing circuit, LED driver circuit, and side-emitting lamp circuit. The power supply and communication circuit consists of connector CN1, TVS diode D1, capacitors C1, C2, C3, C4, C7, C8, electrolytic capacitor EC1, voltage divider resistors R1 and R2, current limiting resistors R3 and R4, rectifier diodes D2 and D3, power supply VCC_5V, and power supply VCC_12V; and completes data exchange between the touch sensing circuit and the range hood system. The touch sensing circuit consists of connector P1, touch chip U1, touch sensors TK1, TK2, TK3, TK4, and TK5, capacitors C10 and C11, resistors R14, R15, R16, R18, R20, R26, and R27, LED driver chip U2, LED1 at touch sensor TK1, LED2 at touch sensor TK2, LED3 at touch sensor TK3, LED4 at touch sensor TK4, LED5 at touch sensor TK5, and power supply VCC_5V. After the touch sensing circuit collects the touch signal, it transmits the control command to the range hood system and the LED driver circuit. After receiving the control command, the range hood system controls the range hood's lighting function, constant suction function, low fan speed function, high fan speed function, and on / off function according to the control command. The LED driving circuit consists of an LED driver chip U2, resistors R30 and R31, capacitors C12 and C13, and a power supply VCC_5V. Resistors R30, R31, C12, and C13 are connected in parallel to the LED driver chip U2. The side-emitting lamp circuit includes an LED array. Forty side-emitting lamps are connected in parallel to form an LED array and are connected to the LED driver chip U2. When the LED driver chip U2 receives an IIC signal from the touch chip U1, it controls the LED array to turn on and off according to the signal. After receiving a control command, the LED driver circuit controls the switching of the side-emitting lamp circuit according to the control command.

2. The multi-mode backlight control circuit based on touch sensing according to claim 1, characterized in that: The connector CN1 includes 8 pins, designated as pins 1, 2, 3, 4, 5, 6, 7, and 8. Pin 1 of connector CN1 is connected to the power supply VCC_12V; pin 2 of connector CN1 is connected to ground; pin 3 of connector CN1 is connected in series with current-limiting resistor R3 and then connected to TXD; pin 4 of connector CN1 is connected in series with current-limiting resistor R4 and then connected to RXD; pin 5 of connector CN1 is connected in parallel with electrolytic capacitor EC1, with one end connected to the power supply VCC_5V and the other end connected to ground; pins 6, 7, and 8 of connector CN1 are connected to ground; TXD represents the communication interface for transmitting data, and RXD represents the communication interface for receiving data. The anode of rectifier diode D2 is connected to RXD, and the cathode is connected to ground; the anode of rectifier diode D3 is connected to TXD, and the cathode is connected to ground; capacitors C7 and C8 are connected in parallel, with one end connected to TXD and the other end connected to ground; capacitors C8 and C7 are connected in parallel, with one end connected to RXD and the other end connected to ground; voltage divider resistors R1 and R2 are connected in parallel, with one end connected to TXD and the other end connected to power supply VCC_5V; voltage divider resistors R2 and R1 are connected in parallel, with one end connected to RXD and the other end connected to power supply VCC_5V. The capacitors C1, C2, C3, C4 and TVS diode D1 are connected in parallel. After the TVS diode D1 is connected in parallel with capacitors C1, C2, C3 and C4, the anode is connected to the power supply VCC_5V and the cathode is connected to the ground wire.

3. The multi-mode backlight control circuit based on touch sensing according to claim 2, characterized in that: The power supply and communication circuit includes a power supply circuit and a communication circuit; The power supply circuit, after receiving the power supply, uses TVS diode D1 for transient voltage suppression; it uses electrolytic capacitor EC1, capacitor C1, capacitor C2, capacitor C3 and capacitor C4 for filtering to eliminate high-frequency noise and obtain a stable DC voltage to supply power to the power supply and communication circuit; the power supply is then filtered by capacitor C7 and capacitor C8 before supplying power to the touch sensing circuit, LED driver circuit and side-emitting lamp circuit. The communication circuit, after receiving power, generates a stable voltage through voltage divider resistors R1 and R2; TXD, after adjusting the voltage through rectifier diode D2, transmits visible light to indicate the data transmission status; RXD, after adjusting the voltage through rectifier diode D3, uses resistors R3 and R4 to complete the detection signal and protection circuit.

4. The multi-mode backlight control circuit based on touch sensing according to claim 1, characterized in that: The connector P1 includes four pins, namely pins 1, 2, 3 and 4. Pin 1 of connector P1 is connected to power supply VCC_5V; pin 2 of connector P1 is connected to touch chip U1; pin 3 of connector P1 is connected to touch chip U1; pin 4 of connector P1 is connected to ground. Capacitors C10 and C11 are connected in parallel with the touch chip U1, with one end connected to the power supply VCC_5V and the other end connected to ground. Resistor R26 is connected in series with the touch chip U1 at one end and with the LED driver chip U2 at the other end. Resistor R27 is connected in series with the touch chip U1 at one end and with the LED driver chip U2 at the other end. Touch sensor TK1 is connected to the touch chip U1 after being connected in series with resistor R14. Touch sensor TK2 is connected to the touch chip U1 after being connected in series with resistor R15. Touch sensor TK3 is connected to the touch chip U1 after being connected in series with resistor R16. Touch sensor TK4 is connected to the touch chip U1 after being connected in series with resistor R18. The touch sensor TK5 is connected to the touch chip U1 via a series resistor R20. The LED1 at touch sensor TK1, the LED2 at touch sensor TK2, the LED3 at touch sensor TK3, the LED4 at touch sensor TK4, and the LED5 at touch sensor TK5 are connected to the touch chip U1.

5. A multi-mode backlight control circuit based on touch sensing according to claim 1, characterized in that: The touch sensor TK5 and resistor R20 are combined to form an RC network. When the touch sensor TK5 collects a touch signal, it generates a change in the level signal. After the touch chip U1 senses the change in the level signal from the touch sensor TK5, it makes the display light LED5 at the touch sensor TK5 turn on and sends an IIC signal to the LED driver chip and a UART signal to the range hood system. After receiving the signal, the LED driver chip controls the light display of the side-emitting lamp circuit; after receiving the signal, the range hood system starts. When the range hood system is started, the touch sensor TK1 collects the touch signal, and the touch sensor TK1 and the resistor R14 are combined to form an RC network to generate a change in the level signal; When the touch chip U1 senses a change in the level signal, the LED1 indicator light at the touch sensor TK1 becomes constantly lit. And send a UART signal to the range hood system; after receiving the signal, the range hood system starts the range hood lighting function; When the LED1 indicator light at the touch sensor TK1 is constantly on and the range hood lighting function is turned on, the touch sensor TK1 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal, it causes the LED1 indicator light at the touch sensor TK1 to change from a constantly on state to a flashing state, and sends a UART signal to the range hood system to turn off the range hood lighting function. When the LED1 indicator light at the touch sensor TK1 is flashing and the range hood lighting function is off, the touch sensor TK1 collects the touch signal and generates a change in the level signal. After the touch chip U1 senses the change in the level signal, it causes the LED1 indicator light at the touch sensor TK1 to change from flashing to constant light and sends a UART signal to the range hood system to turn on the range hood lighting function. When the LED1 indicator light at the touch sensor TK1 is flashing and the range hood lighting function is off, if the touch sensor TK1 does not collect a touch signal within 30 seconds and the touch chip U1 does not sense a change in the level signal, the LED1 indicator light at the touch sensor TK1 will change from flashing to breathing and send a UART signal to the range hood system to keep the range hood lighting function off. The process of touch sensors TK2, TK3 and TK4 acquiring touch signals is the same as that of touch sensor TK1. After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK2 and resistor R15, it controls the change of the display light LED2 at touch sensor TK2 and sends a UART signal to the range hood system to control the opening and closing of the constant suction function of the range hood. After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK3 and resistor R16, it controls the change of the display light LED3 at touch sensor TK3 and sends a UART signal to the range hood system to control the opening and closing of the range hood's low-power function. After the touch chip U1 senses the change in the level signal generated by the RC network composed of touch sensor TK4 and resistor R18, it controls the change of the display light LED4 at touch sensor TK4 and sends a UART signal to the range hood system to control the opening and closing of the range hood's high-power function. When the range hood system is started, the touch sensor TK5 collects the touch signal and generates a change in the level signal; After the touch chip U1 senses the change in the level signal from the touch sensor TK5, it causes the LED5 indicator light at the touch sensor TK5 to change from a constantly lit state to an off state, and sends an IIC signal to the LED driver chip and a UART signal to the range hood system. After receiving the signal, the LED driver chip controls the side-emitting lamp circuit to turn off the light. After receiving the signal, the range hood system turns off the range hood system.

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