Liquid crystal screen driving circuit

Abstract

The utility model discloses a liquid crystal screen driving circuit, and aims to provide stable driving and backlight support for a liquid crystal screen. The circuit comprises a core board processor, an LVDS communication interface, an ESD protection circuit, a liquid crystal backlight driving circuit, a liquid crystal driving voltage conversion circuit, a charge pump circuit and a liquid crystal screen socket. The core board processor transmits image data and clock signals to the liquid crystal screen socket through the LVDS interface, the anti-static capacity is improved through the ESD protection circuit, and stable operation of the system is guaranteed. The liquid crystal backlight driving circuit provides backlight current and brightness adjusting functions, and the liquid crystal driving voltage conversion circuit is responsible for converting an input power supply into driving voltage required by a liquid crystal screen. The charge pump circuit generates positive and negative bias voltages, and the display effect is optimized. According to the utility model, the optimized design improves the efficiency and compatibility of the drive circuit, adapts to various liquid crystal screen models, and enhances the reliability and adaptability of a liquid crystal display system.

Description

TECHNICAL FIELD

[0001] The utility model relates to a liquid crystal screen drive circuit, be applicable to the liquid crystal screen drive of LVDS interface, can adjust voltage according to the different demand of liquid crystal screen, compatible with a variety of LVDS interface's liquid crystal screen, mainly applied to the field of liquid crystal screen drive. BACKGROUND

[0002] With the rapid development of science and technology, liquid crystal display technology has been widely used in various electronic devices, especially in automobiles, consumer electronics and industrial equipment. Vehicle-mounted devices gradually shift from traditional mechanical instruments to modern electronic displays, driving the growth of demand for large-size liquid crystal screens. The rise of new energy vehicles has accelerated this trend, and vehicle-mounted displays have become an important part of information interaction and entertainment systems.

[0003] However, the normal operation of liquid crystal screens depends on multiple different voltages and stable current supply. Due to unstable power supply voltage and mismatched current, liquid crystal screens may not display normally or be damaged. This situation is particularly evident in high-temperature, low-temperature or complex electromagnetic environments, posing a challenge to the reliability of liquid crystal display systems. In addition, traditional voltage conversion schemes often require additional conversion chips, not only increasing the complexity of the system, but also increasing production costs.

[0004] Therefore, it is particularly important to develop an efficient, stable and compatible driving circuit for a variety of liquid crystal screens. SUMMARY

[0005] In view of the problems existing in the prior art, the utility model provides a liquid crystal screen drive circuit, which can flexibly adjust the supply voltage and current according to the requirements of different models of liquid crystal screens, ensuring the stability and reliability of the liquid crystal screen under various working conditions. This not only improves the adaptability of the liquid crystal display system, but also reduces maintenance costs and improves user experience.

[0006] In order to realize the above-mentioned purpose, the technical scheme of the utility model is: a liquid crystal screen driving circuit, including core board treater, LVDS communication interface, ESD protection circuit, liquid crystal backlight driving circuit, liquid crystal drive voltage conversion circuit, charge pump circuit and liquid crystal screen socket, the core board treater is connected with the liquid crystal screen socket through the LVDS communication interface data line and clock line, is used for transmitting image data signal and clock signal, the ESD protection circuit is connected with the LVDS communication interface, is used for preventing electrostatic discharge and surge voltage from damaging liquid crystal screen and core board treater;The liquid crystal backlight driving circuit is connected with the LED + port and LED - port of the liquid crystal screen socket, and receives the PWM signal provided by the core board treater, is used for providing stable voltage and current for liquid crystal screen backlight, and adjusts the brightness of liquid crystal screen backlight;The liquid crystal drive voltage conversion circuit is connected with the liquid crystal screen socket, and is used for converting the input power voltage into the drive voltage AVDD required for the working of liquid crystal screen;The charge pump circuit is connected with the liquid crystal drive voltage conversion circuit and the liquid crystal screen socket, and is used for providing the forward bias voltage VGH and the negative bias voltage VGL for the liquid crystal screen.

[0007] The liquid crystal screen driving circuit of the utility model successfully overcomes the problem of liquid crystal screen burning and damage caused by voltage mismatch, improves the stable power supply of liquid crystal screen under different working conditions, and enhances the stability and reliability.

[0008] In addition, the utility model has the function of preventing electrostatic discharge from damaging the liquid crystal screen, provides stable current for the backlight of the liquid crystal screen, and supports multiple different working voltages. By isolating the liquid crystal screen from the processor through the TVS tube, additional protection is provided for the liquid crystal screen. The TVS tube can absorb instantaneous high-energy pulses to prevent irreversible damage to the liquid crystal screen and the processor caused by electrostatic discharge or surge impact.

[0009] The TPS61165 high-brightness white LED driver can provide stable current for the liquid crystal screen under different working conditions, ensure uniform brightness of the backlight LED lamp, and achieve good visual effect. At the same time, the duty cycle of the PWM wave is adjusted to control the output voltage and current, and the brightness of the liquid crystal screen is controlled. The LM2733 boost converter provides stable voltage AVDD for the liquid crystal drive, ensuring efficient and stable operation of the liquid crystal screen.

[0010] The charge pump technology is introduced to generate the VGH and VGL voltages required by the liquid crystal screen, and compared with the traditional voltage conversion chip, the design complexity and production cost of the circuit board are significantly reduced. In addition, the charge pump can quickly respond to different load changes and continuously output stable voltage, thereby greatly improving the overall reliability of the system.

[0011] In summary, the liquid crystal screen driving circuit of the utility model has remarkable advantages in improving the liquid crystal display performance, reducing the maintenance cost and enhancing the system reliability, and shows wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 The circuit structure diagram of the utility model is shown in the figure;

[0013] Figure 2 The LVDS communication interface and the ESD protection circuit of the utility model are shown in the figure;

[0014] Figure 3 The principle diagram of the liquid crystal backlight driving circuit of the utility model is shown in the figure;

[0015] Figure 4 The principle diagram of the liquid crystal driving voltage conversion circuit of the utility model is shown in the figure;

[0016] Figure 5 The working principle diagram of the charge pump circuit of the utility model is shown in the figure. DETAILED DESCRIPTION

[0017] In order to more clearly understand the utility model, the utility model is described in detail in combination with the drawings and examples.

[0018] As Figure 1 shown, the utility model provides a kind of liquid crystal screen driving circuit, including core board processor, LVDS communication interface, ESD protection circuit, liquid crystal backlight driving circuit, liquid crystal driving voltage conversion circuit, charge pump boost circuit and liquid crystal screen socket XS7.

[0019] Core board processor is responsible for data transmission and signal processing, is connected with liquid crystal screen socket XS7 by the data line and clock line of LVDS communication interface, for transmitting image data signal and clock signal to drive liquid crystal screen to show content.Equipped ESD protection circuit can effectively prevent electrostatic discharge and surge voltage from damaging liquid crystal screen and core board processor, thereby enhancing the anti-static ability of system, ensure the stability of circuit operation.

[0020] The liquid crystal backlight driving circuit is powered by 5V voltage, connected with LED+ and LED- ports of the liquid crystal screen socket XS7, and receives the PWM signal input provided by the core board processor. The circuit provides stable voltage and current for the liquid crystal screen backlight matrix, ensures the uniformity of the backlight, and realizes precise control of the brightness.

[0021] The liquid crystal driving voltage conversion circuit is also driven by 5V voltage, connected with the AVDD port of the liquid crystal screen socket XS7 and the charge pump voltage boosting circuit through the connecting line, and provides the required driving voltage AVDD for the liquid crystal screen. The charge pump voltage boosting circuit is connected with the VGH and VGL ports in the liquid crystal screen socket XS7 respectively, used for generating the bias voltage VGH and VGL required for driving the liquid crystal screen. These voltages are transmitted to the driving unit of the liquid crystal screen through the liquid crystal screen socket XS7, ensuring the normal display performance of the liquid crystal screen.

[0022] Figure 2 The connection diagram of the LVDS communication interface and its ESD protection circuit is shown in the figure, including the data line and clock line of the LVDS communication interface, and ESD protection devices U1, U2 and U3, used for improving the stability and safety of data transmission. The specific connection of the LVDS communication interface data line and clock line and the ESD protection circuit is as follows: the data line LVDS_D0_N is connected with the 7th and 4th pins of the ESD protection device U1, the data line LVDS_D0_P is connected with the 6th and 5th pins of the ESD protection device U1, the data line LVDS_D1_N is connected with the 10th and 1st pins of the ESD protection device U2, the data line LVDS_D1_P is connected with the 9th and 2nd pins of the ESD protection device U2, the data line LVDS_D2_N is connected with the 7th and 4th pins of the ESD protection device U2, the data line LVDS_D2_P is connected with the 6th and 5th pins of the ESD protection device U2, the data line LVDS_CLK_N is connected with the 10th and 1st pins of the ESD protection device U3, the data line LVDS_CLK_P is connected with the 9th and 2nd pins of the ESD protection device U3, the data line LVDS_D3_N is connected with the 7th and 4th pins of the ESD protection device U3, the data line LVDS_D3_P is connected with the 6th and 5th pins of the ESD protection device U3, and the 8th pins of the ESD protection devices U1, U2 and U3 are grounded GND.

[0023] LVDS is a low-swing differential signaling technology that enables high-speed signal transmission of hundreds of Mbps over differential PCB traces or balanced cables, while its low voltage swing and low current drive output have the advantages of low noise and low power consumption. Since LVDS signal belongs to high-speed signal, its integrity needs to be concerned to avoid signal distortion in the transmission process. In order to ensure signal quality, impedance matching of source end and load end needs to be considered in PCB design to reduce reflection and crosstalk, thereby improving the integrity of high-speed signal and the stability of circuit. The model of ESD protection devices U1, U2 and U3 is UBQ10A05L04HI, which is a ultra-low capacitance TVS array specially designed for high-speed data interface. This series of products are designed to protect sensitive components connected to high-speed data and transmission lines, and can effectively prevent overvoltage caused by electrostatic discharge (ESD), cable discharge event (CDE) and electrical fast transient (EFT). The typical capacitance between I / O pins is only 0.3 pF, which can be applied to circuits with frequency exceeding 3 GHz while maintaining signal strength unaffected. This design supports wiring directly through the device, thus simplifying PCB layout design and improving wiring flexibility. With its small size, low capacitance and high ESD protection characteristics, this series of products have become an ideal solution for high-speed circuit applications such as HDMI, UDI, Display Port, MDDI, Serial ATA and Infiniband.

[0024] As Figure 3As shown, the liquid crystal backlight drive circuit is connected as follows: 5.0V_LVDS (5V power supply) is connected to one end of the magnetic bead L13, the other end of the magnetic bead L13 is connected to the inductor L14, the capacitor C176, the capacitor C175 and the VIN (6-pin) of the chip N8, the other end of the capacitor C176 and the capacitor C175 is grounded GND; the BL_PWM_LVDS signal output by the core processor is connected to one end of the resistor R198, the other end of the resistor R198 is connected to the resistor R199 and the CTRL (5-pin) of the chip N8, the other end of the resistor R199 is grounded GND, the COMP (2-pin) of the chip N8 is connected to one end of the capacitor C297, the other end of the capacitor C297 is grounded GND, the EP (7-pin) of the chip N8 and the GND (3-pin) are grounded GND together; the SW (4-pin) of the chip N8 is connected to the anode of the diode VD1 and the other end of the inductor L14, the FB (1-pin) of the chip N8 is connected to the resistor R195 and one end of the resistor R90, the cathode of the diode VD1 is connected to the other end of the resistor R195, the capacitor C173, one end of the capacitor C174, the cathode of the diode VD6, LED+ and the test point TP8; the other end of the capacitor C173 and the capacitor C174 is grounded GND; the other end of the resistor R90 is connected to the resistor R197, the resistor R91, one end of the resistor R333, the anode of the diode VD6, LED- and the test point TP9; the other end of the resistor R197, the resistor R91 and the resistor R333 is grounded together.

[0025] The liquid crystal backlight drive circuit adopts 5V power supply. The power supply 5V_LVDS is connected to the 6-pin VIN of the LED driver chip N8 through the magnetic bead L13 and the filter capacitors C175 and C176 to provide the required electrical energy for the chip boost conversion. The core board provides a group of PWM signals, which are divided by resistors R198 and R199 and then connected to the 5-pin CTRL of the LED driver chip N8. By adjusting the duty cycle of the PWM signal, the output voltage of the boost circuit is controlled, thereby changing the current flowing through the backlight of the liquid crystal screen and realizing the adjustment of the screen brightness. At the output end, the 4-pin SW of the LED driver chip N8 is connected to the anode of the diode VD1, and the diode realizes the function of one-way conduction, and its cathode is connected to the feedback resistors R195 and R90 and the 1-pin FB of the LED driver chip N8. The output voltage value of the LED driver chip N8 can be adjusted by dividing through R90. The cathode of the diode VD1 is also connected to the filter capacitors C173 and C174 at the output end, and further connected to the voltage stabilizing tube VD6 to prevent damage to external devices caused by excessive voltage. The LED+ and LED- at the output end are the interfaces of the backlight of the liquid crystal screen. By adjusting the resistance values of R91, R197 and R333, the division ratio and the current value of the backlight can be changed. The backlight current value directly affects the screen brightness, so the brightness control is realized by adjusting the current.

[0026] The model of the LED driver chip N8 in the liquid crystal backlight driving circuit is TPS61165DRVR, which is a high-brightness white light LED driver specially designed for small and medium-sized LCD bias power supply and white LED backlight power supply. TPS61165DRVR works at a switching frequency of up to 1 MHz, has an internal 400 mA switching current limit, can provide a lower output voltage ripple, and allows the use of smaller inductors in low-power applications. By matching appropriate resistors and capacitors, the output voltage and current of TPS61165DRVR can be adjusted to meet the specific needs of liquid crystal screen backlight driving. In this way, high-efficiency and stable power supply support can be provided for the backlight LED of the liquid crystal screen, meeting the requirements of small LCD backlight applications.

[0027] In the liquid crystal backlight driving circuit, the feedback resistor is composed of a voltage dividing circuit formed by R195, R90, R197, R91 and R333. In the case where the liquid crystal screen is not connected, since the resistance values of R197, R91 and R333 are negligible compared to R195 and R90, the feedback voltage can be calculated through R195 and R90. Given that the feedback voltage of TPS61165DRVR is V FB = 200 mV, and the resistance values of R195 and R90 are 220 K and 2.4 K respectively, the calculation formula of the output voltage V OUT is: V OUT = [(R195 + R90) / R90] * V FB , and by substituting the parameters, the output voltage V OUT is 18.5 V. When the liquid crystal screen is connected, the feedback resistor network includes R195, R90, R197, R91 and R333, and the parallel resistance of R197, R91 and R333 can be denoted as R0. At this time, the current flowing through the liquid crystal screen is represented by the sum of the currents flowing through R197, R91 and R333, denoted as I0; and the current flowing through R195 and R90 is denoted as I1. According to the characteristics of the circuit, the calculation formula of I1 is: I1 = [V FB - (I0 * R0)] / R90, and thus the expression of the output voltage V OUT is: V OUT = (R195 + R90) * I1. Through the above formula, the output voltage value when the liquid crystal screen reaches the maximum brightness (i.e. the maximum current provided by the backlight circuit) can be calculated. In addition, by adjusting the duty cycle of the input PWM wave, the brightness of the backlight lamp can be finely adjusted to meet different brightness requirements and ensure stable operation of the liquid crystal screen.

[0028] The liquid crystal drive voltage conversion circuit and the charge pump circuit are as follows Figure 4The specific circuit connection is shown as follows: one end of 5.0V_LVDS (5V power supply) is connected with inductor L5, the other end of inductor L5 is connected with capacitor C34, capacitor C35, inductor L4, one end of resistor R11 and VIN (5 pin) of chip N5, the other end of capacitor C34 and capacitor C35 is connected with ground GND, the other end of resistor R11 is connected with SHDN (4 pin) of chip N5; the other end of inductor L4 is connected with SW (1 pin) of chip N5, one end of resistor R17 and anode of diode VD9, the other end of resistor R17 is connected with capacitor C20 and one end of capacitor C36; cathode of diode VD9 is connected with resistor R16, capacitor C27, capacitor C35, resistor R20, capacitor C28, 12V6_LVDS and test point TP5, and is connected with AVDD through resistor R19; FB (3 pin) of chip N5 is connected with resistor R14, one end of resistor R15 and the other end of capacitor C27, GND (2 pin) of chip N5 is connected with resistor R15 and the other end of capacitor C35 and then connected with ground GND; the other end of resistor R14 is connected with the other end of resistor R16; the other end of capacitor C20 is connected with pin 3 of triode VT1, pin 1 of triode VT1 is connected with the other end of resistor R20; pin 2 of triode VT1 is connected with capacitor C31 and one end of resistor R22, the other end of capacitor C31 is connected with ground GND, the other end of resistor R22 is connected with cathode of diode VD3, resistor R29, one end of capacitor C32, 22V_LVDS and test point TP6, and is connected with VGH through resistor R21, anode of diode VD3, resistor R28 and the other end of capacitor C32 are connected with ground GND; the other end of capacitor C36 is connected with pin 3 of triode VT2, pin 2 of triode VT2 is connected with ground GND; pin 1 of triode VT2 is connected with capacitor C37 and one end of resistor R32, the other end of capacitor C37 is connected with ground GND, the other end of resistor R32 is connected with anode of diode VD5, resistor R33, one end of capacitor C38, -7V_LVDS and test point TP7, and is connected with VGL through resistor R31, cathode of diode VD5, resistor R33 and the other end of capacitor C38 are connected with ground GND.

[0029] The liquid crystal drive voltage conversion circuit is also powered by the 5V power supply. The power supply 5V_LVDS is connected to the 5-pin VIN of the integrated circuit N5 through the magnetic bead L5 and the filter capacitors C34 and C15. The SW pin of the integrated circuit N5 is an output terminal, connected to one end of the diode VD9 and the feedback resistors R16, R14, and R15. The 3-pin FB of the integrated circuit N5 is a feedback pin, used to adjust the output voltage value. One end is connected to the capacitors C20 and C36 through resistors. This capacitor and the transistors VT1 and VT2 form a Dickson charge pump circuit, which generates a double voltage for the VGH of the liquid crystal screen and a negative voltage for the VGL of the liquid crystal screen. The connected zener diodes VD3 and VD5 prevent the liquid crystal screen from being burned out by excessive voltage.

[0030] The liquid crystal drive voltage conversion circuit takes the LM2733X step-up converter chip N5 and the charge pump circuit as the core part. The LM2733X adjusts the output voltage through the feedback resistors R16, R14, and R15, and according to the formula VOUT=[(R16+R14+R15) / R15]*VFB, the driving voltage AVDD provided for the liquid crystal screen can be obtained. The charge pump circuit is composed of the transistors VT1 and the capacitors C20 and C31, which can generate the driving voltages VGH and VGL required by the liquid crystal screen. This design not only simplifies the circuit and reduces production costs, but also quickly responds and stably outputs voltage, improving the reliability of the entire system. Through the cooperative work of the step-up converter and the charge pump circuit, this liquid crystal drive voltage conversion circuit can flexibly provide the required efficient and stable driving voltage for the liquid crystal screen.

[0031] The working principle of the charge pump circuit is shown in Figure 5 The transistor VT1 is equivalent to two diodes VD1 and VD2 connected in series. The capacitor C20 is a boost capacitor, and the capacitor C31 is an output capacitor. The working principle of the charge pump is to store and transfer energy through capacitors, thereby achieving voltage boosting or reducing. Figure 5 The input voltage V1 is IN The input voltage V1 is SW a high-frequency pulse signal V2. When V SW is at point a, the capacitors C20 and C31 are charged to V1 due to the action of V IN . When V SW is at point b, the voltage of capacitor C20 is V1, and the voltage of V SW is V2. Therefore, the output voltage V OUT is V1+V2. Since capacitors C20 and C31 share charges, the potentials of capacitors C20 and C31 should be (V1+V2+V1) / 2. When V SWAt c point, the capacitor C20 is charged to V1 again, and due to the unidirectional conduction of the diode VD2, the C31 potential is still (V1+V2+V1) / 2; when V SW At d point, the capacitor C20 is charged to V1+V2 again, and the charge sharing occurs again, that is, the C31 potential is pulled up to [(V1+V2)+((V1+V2+V1) / 2)] / 2 again; in this way, the capacitor C31 will eventually be equal to the potential of the capacitor C20, and the voltage boosting effect is achieved. However, this circuit needs to ensure that the output power consumption is lower than the charging speed of the capacitor C31, otherwise it cannot be charged and the voltage boosting effect cannot be achieved, and therefore the load carrying capacity is not strong and it can only be used in low-power circuits. In summary, the charge pump is gradually applied to more fields due to its low cost and simple design.

[0032] The utility model discloses a LVDS communication interface realizes the data communication of core board and display screen, and the voltage and current needed for the working of liquid crystal screen LED backlight matrix are provided through liquid crystal backlight drive circuit, and the voltage needed for the circuit of liquid crystal screen is provided through liquid crystal drive voltage conversion circuit. U1, U2, U3 are placed at the LVDS communication interface, and transient voltage suppressor UBQ10A05L04HI, namely TVS diode, is used to realize the resistance against electrostatic discharge, power surge and other transient overvoltage phenomena. The PWM wave generated by chip N8 and core board realizes the backlight drive of liquid crystal screen. The driving voltage AVDD needed for the working of liquid crystal screen is realized through chip N5. The diel charge pump circuit is formed by triode VT1, VT2 and capacitor C20, C31, C36, C37, and the driving voltage VGH and VGL for liquid crystal screen are provided through voltage stabilizing tube MM3Z24VT1G and MM3Z7V5T1G.

[0033] The utility model is used to CIR - LTE vehicle terminal's MMI, mainly used for video call, map display and other functional field. This utility model relies on M3568-4GF16GLI - T core board to carry out video processing, selects 8 inch's LCD liquid crystal screen TM080TDGP01-00, and the resolution is 1024x768. The core board and liquid crystal screen carry out communication through high -speed communication interface LVDS. Liquid crystal backlight drive is realized with high -frequency voltage -boosting converter TPS61165DRVR, and the output terminal voltage and current are controlled through peripheral resistance capacitor, and the liquid crystal screen backlight brightness is controlled through PWM wave, so that it is enough to meet the working demand of liquid crystal screen, guarantees the stable reliable of liquid crystal screen. Liquid crystal drive voltage conversion circuit adopts LM2733X and dickson charge pump to realize the drive of liquid crystal screen. LM2733X is a kind of high efficiency, low voltage difference voltage -boosting converter, has wide input voltage range (1.6V to 18V), output voltage is high (can reach 34V), the highest efficiency can reach 92% and other characteristics. Dickson voltage pump is a kind of voltage doubler circuit, can be higher voltage to low voltage, compared with other voltage -boosting circuit, dickson voltage pump has higher efficiency and simple circuit structure, the basic principle of this circuit is through capacitor and switch to realize the transfer and accumulation of electric charge, so that the output voltage is doubled constantly, to reach the purpose of voltage -boosting. In summary, the liquid crystal screen drive circuit of the utility model realizes the high -efficient, stable drive to liquid crystal screen through reasonable circuit design and component selection, and has good ESD protection ability simultaneously, ensures the long -term stable operation of circuit.

Claims

1. A liquid crystal display (LCD) screen driving circuit, comprising a core board processor, an LVDS communication interface, an ESD protection circuit, an LCD backlight driving circuit, an LCD driving voltage conversion circuit, a charge pump circuit, and an LCD screen socket, characterized in that: The core board processor is connected with the liquid crystal screen socket through the LVDS communication interface data line and clock line, for transmitting image data signal and clock signal, the ESD protection circuit is connected with the LVDS communication interface, for preventing electrostatic discharge and surge voltage from damaging the liquid crystal screen and the core board processor; the liquid crystal backlight driving circuit is connected with the LED+ port and LED- port of the liquid crystal screen socket, and receives the PWM signal provided by the core board processor, for providing stable voltage and current for the liquid crystal screen backlight, and adjusting the brightness of the liquid crystal screen backlight; the liquid crystal drive voltage conversion circuit is connected with the liquid crystal screen socket, for converting the input power voltage into the drive voltage AVDD required by the liquid crystal screen working; the charge pump circuit is connected with the liquid crystal drive voltage conversion circuit and the liquid crystal screen socket, for providing the positive bias voltage VGH and the negative bias voltage VGL for the liquid crystal screen.

2. The liquid crystal panel driving circuit according to claim 1, wherein The LVDS communication interface is connected with the ESD protection circuit through data line and clock line, and the specific circuit is: the data line LVDS_D0_N is connected with the 7th pin and the 4th pin of the ESD protection device U1, the data line LVDS_D0_P is connected with the 6th pin and the 5th pin of the ESD protection device U1, the data line LVDS_D1_N is connected with the 10th pin and the 1st pin of the ESD protection device U2, the data line LVDS_D1_P is connected with the 9th pin and the 2nd pin of the ESD protection device U2, the data line LVDS_D2_N is connected with the 7th pin and the 4th pin of the ESD protection device U2, the data line LVDS_D2_P is connected with the 6th pin and the 5th pin of the ESD protection device U2, the data line LVDS_CLK_N is connected with the 10th pin and the 1st pin of the ESD protection device U3, the data line LVDS_CLK_P is connected with the 9th pin and the 2nd pin of the ESD protection device U3, the data line LVDS_D3_N is connected with the 7th pin and the 4th pin of the ESD protection device U3, the data line LVDS_D3_P is connected with the 6th pin and the 5th pin of the ESD protection device U3, and the 8th pin of the ESD protection devices U1, U2 and U3 is grounded GND.

3. The liquid crystal panel driving circuit according to claim 1, wherein The specific connection of the liquid crystal backlight driving circuit is: 5.0V_LVDS is connected with one end of the magnetic bead L13, the other end of the magnetic bead L13 is respectively connected with the inductor L14, the capacitor C176, the capacitor C175 and the VIN of the chip N8, the other end of the capacitor C176 and the capacitor C175 is grounded GND; the BL_PWM_LVDS signal output by the core processor is connected with one end of the resistor R198, the other end of the resistor R198 is respectively connected with the resistor R199 and the CTRL of the chip N8, the other end of the resistor R199 is grounded GND, the COMP of the chip N8 is connected with one end of the capacitor C297, the other end of the capacitor C297 is grounded GND, the EP and the GND of the chip N8 are grounded GND together; the SW of the chip N8 is respectively connected with the anode of the diode VD1 and the other end of the inductor L14, the FB of the chip N8 is respectively connected with the resistor R195 and one end of the resistor R90, the cathode of the diode VD1 is connected with the other end of the resistor R195, one end of the capacitor C173, one end of the capacitor C174, the cathode of the diode VD6, LED+ and the test point TP8; the other end of the capacitor C173 and the capacitor C174 is grounded GND; the other end of the resistor R90 is respectively connected with the resistor R197, the resistor R91, one end of the resistor R333, the anode of the diode VD6, LED- and the test point TP9; the other end of the resistor R197, the resistor R91 and the resistor R333 is grounded together.

4. The liquid crystal panel driving circuit according to claim 1, wherein The specific connection of the liquid crystal drive voltage conversion circuit and the charge pump circuit is as follows: one end of 5.0V_LVDS is connected with inductor L5, the other end of inductor L5 is connected with capacitor C34, capacitor C35, inductor L4, one end of resistor R11 and VIN of chip N5 respectively, the other ends of capacitor C34 and capacitor C35 are connected with ground GND together, the other end of resistor R11 is connected with SHDN of chip N5; the other end of inductor L4 is connected with SW of chip N5, one end of resistor R17 and anode of diode VD9 respectively, the other end of resistor R17 is connected with capacitor C20 and one end of capacitor C36 respectively; cathode of diode VD9 is connected with resistor R16, capacitor C27, capacitor C35, resistor R20, capacitor C28, 12V6_LVDS and test point TP5 respectively, and is connected with AVDD through resistor R19; FB of chip N5 is connected with the other end of resistor R14, one end of resistor R15 and the other end of capacitor C27 respectively, GND of chip N5 is connected with the other end of resistor R15 and the other end of capacitor C35 respectively and then connected with ground GND; the other end of resistor R14 is connected with the other end of resistor R16; the other end of capacitor C20 is connected with pin 3 of triode VT1 respectively, pin 1 of triode VT1 is connected with the other end of resistor R20; pin 2 of triode VT1 is connected with capacitor C31 and one end of resistor R22, the other end of capacitor C31 is connected with ground GND, the other end of resistor R22 is connected with cathode of diode VD3, resistor R29, one end of capacitor C32, 22V_LVDS and test point TP6 respectively, and is connected with VGH through resistor R21, anode of diode VD3, resistor R28 and the other end of capacitor C32 are connected with ground GND together; the other end of capacitor C36 is connected with pin 3 of triode VT2 respectively, pin 2 of triode VT2 is connected with ground GND; pin 1 of triode VT2 is connected with capacitor C37 and one end of resistor R32 respectively, the other end of capacitor C37 is connected with ground GND, the other end of resistor R32 is connected with anode of diode VD5, resistor R33, one end of capacitor C38, -7V_LVDS and test point TP7 respectively, and is connected with VGL through resistor R31, cathode of diode VD5, resistor R33 and the other end of capacitor C38 are connected with ground GND together.

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