Screen voltage adaptation circuit and vehicle-mounted central control screen

Abstract

The utility model provides a screen voltage adaptation circuit and a vehicle-mounted central control screen. The circuit comprises an MIPI display central controller, a PWM wave modulation circuit and a high and low voltage output circuit, the PWM wave modulation circuit comprises a first resistor, a second resistor and a switching tube, and the high and low voltage output circuit comprises a power supply chip, a third resistor, a high voltage output circuit, a low voltage output circuit and a feedback circuit. When a signal of a liquid crystal display analog voltage end of the MIPI display central controller is in a low-voltage level, the signal is fed back to the power supply chip through the eighth resistor, so that the power supply chip outputs low-voltage power from the low-voltage output circuit according to feedback information to adapt to a display screen with low working voltage, and the display effect of the MIPI display central controller is improved. When the signal of the liquid crystal display analog voltage end of the MIPI display central controller is a high-voltage level, the power supply chip outputs high voltage from the high-voltage output circuit according to the feedback information so as to adapt to a display screen with high working voltage, so that the same circuit can adapt to different types of central control display screens.

Description

Technical Field

[0001] The present disclosure relates to the technical field of vehicle-mounted display screens, and in particular to a screen voltage adaptation circuit and a vehicle-mounted central control screen. Background Art

[0002] At present, more and more cars are using central control display screens. The setting of the central control display screen can give users a better user experience, and can also provide users with a visual experience to meet users' needs.

[0003] Currently, different types of in-vehicle central control screens use different types of circuit boards, which means that the circuits in each circuit board can only adapt to a single type of central control display screen and cannot adapt to another type of central control display screen. As a result, the circuits in the circuit board have poor adaptability to other types of central control display screens, and cannot guarantee the normal operation of the in-vehicle central control screen.

[0004] Therefore, a circuit is needed to adapt to different types of central control display screens. Utility Model Content

[0005] The purpose of the present disclosure is to overcome the deficiencies in the prior art and to provide a screen voltage adaptation circuit and a vehicle-mounted central control screen that can enable a single circuit to adapt to different types of central control display screens.

[0006] The purpose of this disclosure is achieved through the following technical solutions:

[0007] A screen voltage adaptation circuit, used to adapt to different types of display screens, including:

[0008] MIPI display central controller;

[0009] The PWM wave modulation circuit includes a first resistor, a second resistor, and a switch tube. The first end of the first resistor is used to connect to the pulse width modulation voltage terminal in series. The second end of the first resistor is connected to the control terminal of the switch tube. The first end of the switch tube is respectively connected to the first end of the second resistor and the series voltage terminal of the MIPI display central controller. The second end of the second resistor is connected to the liquid crystal display analog voltage terminal of the MIPI display central controller. The second end of the switch tube is grounded.

[0010] A high and low voltage output circuit is used to output high voltage or low voltage according to the type of display screen, including a power supply chip, a third resistor, a high voltage output circuit, a low voltage output circuit and a feedback circuit. The first end of the third resistor is used to connect to the PWM analog voltage end, the second end of the third resistor is connected to the enable end of the power supply chip, the switching output end of the power supply chip is respectively connected to the input end of the high voltage output circuit and the low voltage output circuit, the output end of the high voltage output circuit is connected to the high voltage end of the MIPI display central controller, and the output end of the low voltage output circuit is connected to the low voltage end of the MIPI display central controller. The feedback circuit includes an eighth resistor and a ninth resistor. The first end of the eighth resistor is respectively connected to the switching output end of the power supply chip and the liquid crystal display analog voltage end of the MIPI display central controller, the second end of the eighth resistor is respectively connected to the feedback end of the power supply chip and the first end of the ninth resistor, and the second end of the ninth resistor is grounded.

[0011] In one embodiment, the low-voltage output circuit includes a first switching diode, a first capacitor, a fourth resistor and a fifth resistor, the control end of the first switching diode is connected to the switching output end of the power supply chip, the upper half end of the first capacitor is connected to the positive end of the first switching diode and the first end of the fourth resistor, the lower half end of the first capacitor is connected to the negative end of the first switching diode, the lower half end of the first capacitor is also grounded, the second end of the fourth resistor is connected to the first end of the fifth resistor, the first end of the fifth resistor is connected to the low-voltage end of the MIPI display central controller, and the second end of the fifth resistor is grounded.

[0012] In one embodiment, the low-voltage output circuit further includes a second capacitor and a Zener diode, the upper half of the second capacitor is respectively connected to the second end of the fourth resistor and the positive end of the Zener diode, and the lower half of the second capacitor is respectively connected to the negative end of the Zener diode and the second end of the fifth resistor.

[0013] In one embodiment, the high-voltage output circuit includes a second switching diode, a third capacitor, a sixth resistor and a seventh resistor. The switching output end of the power supply chip is respectively connected to the control end of the second switching diode, the positive end of the second switching diode and the first end of the eighth resistor, the negative end of the second switching diode is respectively connected to the upper half end of the third capacitor and the first end of the sixth resistor, the lower half end of the third capacitor is grounded, the second end of the sixth resistor is connected to the first end of the seventh resistor, the first end of the seventh resistor is also connected to the high-voltage end of the MIPI display central controller, and the second end of the seventh resistor is grounded.

[0014] In one embodiment, the high and low voltage output circuit further includes a universal diode, a positive end of the universal diode is connected to the output end of the power chip, and a negative end of the universal diode is connected to the positive end of the second switch diode.

[0015] In one embodiment, the feedback circuit further includes a tenth resistor and a fourth capacitor, the first end of the tenth resistor is connected to the first end of the eighth resistor, the second end of the tenth resistor is respectively connected to the upper half end of the fourth capacitor and the liquid crystal display analog voltage end of the MIPI display central controller, and the lower half end of the fourth capacitor is grounded.

[0016] In one embodiment, the high and low voltage output circuit further includes an eleventh resistor, a first end of the eleventh resistor is connected to the second end of the third resistor, and a second end of the eleventh resistor is grounded.

[0017] In one embodiment, the PWM modulation circuit further includes a twelfth resistor, a first end of the twelfth resistor is connected to the first end of the second resistor, and a second end of the twelfth resistor is connected to the series voltage end of the MIPI display central controller.

[0018] In one embodiment, the PWM modulation circuit further includes a fifth capacitor, an upper end of the fifth capacitor is connected to the second end of the twelfth resistor, and a lower end of the fifth capacitor is grounded.

[0019] A vehicle-mounted central control screen comprises a display screen and the screen voltage adaptation circuit described in any one of the above embodiments, wherein the display screen is electrically connected to the power supply end of the screen voltage adaptation circuit.

[0020] Compared with the prior art, the present disclosure has at least the following advantages:

[0021] When the circuit is powered, the central processing unit CPU enables the serial pulse width modulation voltage to turn on the switch tube, so that the PWM modulation circuit is turned on to power the MIPI display central controller. When the signal at the LCD display analog voltage end of the MIPI display central controller is at a low voltage level, the signal is fed back to the power chip through the eighth resistor, so that the power chip outputs low voltage electricity from the low voltage output circuit according to the feedback information to adapt to the display screen with low working voltage. When the signal at the LCD display analog voltage end of the MIPI display central controller is at a high voltage level, the power chip outputs high voltage electricity from the high voltage output circuit according to the feedback information to adapt to the display screen with high working voltage. Therefore, this solution can realize the same circuit to adapt to different types of central control display screens, without the need for a single circuit to adapt to a single type of central control display screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 This is a circuit diagram of a MIPI display central controller in a screen voltage adaptation circuit in one embodiment;

[0024] Figure 2 For Figure 1 The circuit diagram of the PWM modulation circuit connected to the MIPI display central controller is shown;

[0025] Figure 3 For Figure 1 The circuit diagram shown is of the high and low voltage output circuits connected to the MIPI display central controller.

[0026] Figure numerals: 10, screen voltage adaptation circuit; 100, MIPI display central controller; 200, PWM modulation circuit; 300, high and low voltage output circuit; 301, high voltage output circuit; 302, low voltage output circuit; 303, feedback circuit; R173, first resistor; R18, second resistor; R9, third resistor; R102, fourth resistor; R106, fifth resistor; R104, sixth resistor; R107, seventh resistor; R84, eighth resistor; R90, ninth resistor; R108, tenth resistor; R38, eleventh resistor; R171, twelfth resistor; Q17, switch tube; U1, power chip; D7, general diode; D9, first switch diode; D16, second switch diode; C9, first capacitor; C36, second capacitor; C49, third capacitor; C18, fourth capacitor; C51, fifth capacitor; ZD2, voltage regulator diode. DETAILED DESCRIPTION

[0027] To facilitate understanding of the present disclosure, a more comprehensive description of the present disclosure will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present disclosure. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly attached to the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only implementation methods.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. The terms used herein in the specification of this disclosure are intended only to describe specific embodiments and are not intended to limit this disclosure. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] In order to better understand the technical solutions and beneficial effects of the present disclosure, the present disclosure is further described in detail below with reference to specific embodiments:

[0031] See also Figures 1 to 3 , which is a screen voltage adaptation circuit 10 of an embodiment of the present invention, used to adapt to different types of display screens, including a MIPI display central controller 100, a PWM modulation circuit 200 and a high and low voltage output circuit 300.

[0032] like Figure 2 As shown, the PWM modulation circuit 200 includes a first resistor R173, a second resistor R18 and a switch tube Q17. The first end of the first resistor R173 is used to be connected to the pulse width modulation voltage terminal VCOM_PWM3 in series. The second end of the first resistor R173 is connected to the control end of the switch tube Q17. The first end of the switch tube Q17 is respectively connected to the first end of the second resistor R18 and the series voltage terminal VCOM of the MIPI display central controller 100. The second end of the second resistor R18 is connected to the liquid crystal display analog voltage terminal LCD_AVDD of the MIPI display central controller 100. The second end of the switch tube Q17 is grounded. Figure 3As shown, the high and low voltage output circuit 300 is used to output high voltage or low voltage according to the type of display screen, including a power supply chip U1, a third resistor R9, a high voltage output circuit 301, a low voltage output circuit 302 and a feedback circuit 303. The first end of the third resistor R9 is used to connect to the PWM analog voltage terminal AVDD_PWM, the second end of the third resistor R9 is connected to the enable terminal of the power supply chip U1, the switching output terminal of the power supply chip U1 is respectively connected to the input terminal of the high voltage output circuit 301 and the low voltage output circuit 302, and the output terminal of the high voltage output circuit 301 is connected to The high-voltage end VGH of the MIPI display central controller 100 and the output end of the low-voltage output circuit 302 are connected to the low-voltage end VGL of the MIPI display central controller 100. The feedback circuit 303 includes an eighth resistor R84 and a ninth resistor R90. The first end of the eighth resistor R84 is respectively connected to the switching output end of the power chip U1 and the liquid crystal display analog voltage end of the MIPI display central controller 100. The second end of the eighth resistor R84 is respectively connected to the feedback end of the power chip U1 and the first end of the ninth resistor R90. The second end of the ninth resistor R90 is grounded.

[0033] In this embodiment, when the circuit is powered, the central processing unit (CPU) enables the serial pulse width modulation voltage to turn on the switch Q17, so that the PWM modulation circuit 200 is turned on to power the MIPI display central controller 100. When the signal at the liquid crystal display analog voltage terminal of the MIPI display central controller 100 is at a low voltage level, the signal is fed back to the power supply chip U1 through the eighth resistor R84, causing the power supply chip U1 to output low voltage power from the low voltage output circuit 302 based on the feedback information to adapt to the display screen with a low operating voltage. When the signal at the liquid crystal display analog voltage terminal of the MIPI display central controller 100 is at a high voltage level, the power supply chip U1 outputs high voltage power from the high voltage output circuit 301 based on the feedback information to adapt to the display screen with a high operating voltage. This solution allows the same circuit to adapt to different types of central control display screens, eliminating the need for a single circuit to adapt to a single type of central control display screen. Furthermore, the switch Q17 is an NPN transistor with a first terminal as the collector, a second terminal as the emitter, and a control terminal as the base.

[0034] like Figure 3As shown, in one embodiment, the low-voltage output circuit 302 includes a first switching diode D9, a first capacitor C9, a fourth resistor R102 and a fifth resistor R106, the control end of the first switching diode D9 is connected to the switching output end of the power supply chip U1, the upper half end of the first capacitor C9 is connected to the positive end of the first switching diode D9 and the first end of the fourth resistor R102, the lower half end of the first capacitor C9 is connected to the negative end of the first switching diode D9, the lower half end of the first capacitor C9 is also grounded, the second end of the fourth resistor R102 is connected to the first end of the fifth resistor R106, the first end of the fifth resistor R106 is connected to the low-voltage end of the MIPI display central controller 100, and the second end of the fifth resistor R106 is grounded. It is understood that when the power chip U1 receives low-voltage feedback, it turns on the first switching diode D9, and the current passes through the first switching diode D9 and the fourth resistor R102 to output a low-voltage signal to the MIPI display central controller 100. The first capacitor C9 is used to filter the output low voltage and stabilize the voltage between the positive and negative terminals of the first switching diode D9 to prevent voltage fluctuations from damaging circuit components. Furthermore, the low-voltage output circuit 302 also includes a second capacitor C36 and a Zener diode ZD2. The upper half of the second capacitor C36 is connected to the second terminal of the fourth resistor R102 and the positive terminal of the Zener diode ZD2, respectively, and the lower half of the second capacitor C36 is connected to the negative terminal of the Zener diode ZD2 and the second terminal of the fifth resistor R106. It is understood that the Zener diode ZD2 and the second capacitor C36 are both connected in parallel with the fifth resistor R106, and the Zener diode ZD2 is connected in parallel with the second capacitor C36. This can further stabilize the voltage after passing through the fourth resistor R102 and filter the voltage signal to prevent further voltage fluctuations and ensure the normal operation of the display.

[0035] like Figure 3As shown, in one embodiment, the high-voltage output circuit 301 includes a second switching diode D16, a third capacitor C49, a sixth resistor R104, and a seventh resistor R107. The switching output terminal of the power supply chip U1 is respectively connected to the control terminal of the second switching diode D16, the positive terminal of the second switching diode D16, and the first terminal of the eighth resistor R84. The negative terminal of the second switching diode D16 is respectively connected to the upper half terminal of the third capacitor C49 and the first terminal of the sixth resistor R104. The lower half terminal of the third capacitor C49 is grounded. The second terminal of the sixth resistor R104 is connected to the first terminal of the seventh resistor R107. The first terminal of the seventh resistor R107 is also connected to the high-voltage terminal of the MIPI display central controller 100. The second terminal of the seventh resistor R107 is grounded. It can be understood that when the power supply chip U1 receives high-voltage feedback, the second switching diode D16 is turned on, and current passes through the second switching diode D16 and the sixth resistor R104 to output a high-voltage signal to the MIPI display central controller 100. The third capacitor C49 is used to filter and stabilize the output high voltage to prevent voltage fluctuations from damaging circuit components. Furthermore, the high- and low-voltage output circuit 300 also includes a universal diode D7. The positive terminal of the universal diode D7 is connected to the output terminal of the power chip U1, and the negative terminal of the universal diode D7 is connected to the positive terminal of the second switching diode D16. It will be understood that the universal diode D7 is used to unidirectionally flow the output high-voltage current, preventing current backflow and damage to the power chip U1.

[0036] like Figure 3 As shown, in one embodiment, the feedback circuit 303 also includes a tenth resistor R108 and a fourth capacitor C18, the first end of the tenth resistor R108 is connected to the first end of the eighth resistor R84, the second end of the tenth resistor R108 is respectively connected to the upper half of the fourth capacitor C18 and the liquid crystal display analog voltage end of the MIPI display central controller 100, and the lower half of the fourth capacitor C18 is grounded. It can be understood that the feedback circuit 303 collects the analog voltage signal of the MIPI display central controller 100 and feeds the signal back to the power chip U1, wherein the tenth resistor R108 is used to further limit the feedback current to prevent excessive current from breaking through the feedback pin of the power chip U1, and the fourth capacitor C18 is used to filter and stabilize the feedback signal, reduce interference from excess signals, and ensure the normal operation of the feedback circuit 303 and the normal output of the power chip U1.

[0037] like Figure 3 As shown, in one embodiment, the high-low voltage output circuit 300 further includes an eleventh resistor R38, wherein a first terminal of the eleventh resistor R38 is connected to a second terminal of the third resistor R9, and a second terminal of the eleventh resistor R38 is grounded. It will be appreciated that the current from the series-connected pulse-width modulation voltage terminal passes through the third resistor R9 to enable the power chip U1, and a portion of the current passes through the eleventh resistor R38 to ground, thereby preventing overcurrent and protecting the power chip U1 from overcurrent signal breakdown.

[0038] like Figure 2 As shown, in one embodiment, the PWM modulation circuit 200 further includes a twelfth resistor R171, the first end of the twelfth resistor R171 is connected to the first end of the second resistor R18, and the second end of the twelfth resistor R171 is connected to the series voltage end of the MIPI display central controller 100. It can be understood that the current of the liquid crystal display analog voltage end will sequentially pass through the second resistor R18 and the twelfth resistor R171 to power the MIPI display central controller 100, wherein the second resistor R18 and the twelfth resistor R171 are used to limit the current to prevent excessive current from breaking down the MIPI display central controller 100. Furthermore, the PWM modulation circuit 200 further includes a fifth capacitor C51, the upper half of the fifth capacitor C51 is connected to the second end of the twelfth resistor R171, and the lower half is grounded, so as to filter the power supply signal, stabilize the power supply voltage of the MIPI display central controller 100, and prevent the power supply voltage from fluctuating.

[0039] The present disclosure further provides an in-vehicle central control screen, comprising a display screen and the screen voltage adaptation circuit 10 of any of the above-described embodiments, wherein the display screen is electrically connected to a power supply terminal of the screen voltage adaptation circuit 10. It is understood that when the display screen requires a higher operating voltage value, the screen voltage adaptation circuit 10 uses a high-voltage output; when the display screen requires a lower operating voltage value, the screen voltage adaptation circuit 10 uses a low-voltage output, thereby adapting the circuit to a wider range of display screen types.

[0040] Compared with the prior art, the present disclosure has at least the following advantages:

[0041] When the circuit is powered on, the central processing unit CPU enables the serial pulse width modulation voltage to turn on the switch tube Q17, so that the PWM modulation circuit 200 is turned on to power the MIPI display central controller 100. When the signal at the liquid crystal display analog voltage end of the MIPI display central controller 100 is at a low voltage level, the signal is fed back to the power chip U1 through the eighth resistor R84, so that the power chip U1 outputs low voltage electricity from the low voltage output circuit 302 according to the feedback information to adapt to the display screen with low working voltage. When the signal at the liquid crystal display analog voltage end of the MIPI display central controller 100 is at a high voltage level, the power chip U1 outputs high voltage electricity from the high voltage output circuit 301 according to the feedback information to adapt to the display screen with high working voltage. Therefore, this solution can realize that the same circuit can adapt to different types of central control display screens, and there is no need for a single circuit to adapt to a single type of central control display screen.

[0042] The above-described embodiments merely represent several implementation methods of the present disclosure. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the disclosed patent. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the scope of the present disclosure, all of which fall within the scope of protection of the present disclosure. Therefore, the scope of protection of the disclosed patent shall be determined by the appended claims.

Claims

1. A screen voltage adaptation circuit for adapting to different types of display screens, characterized in that: include: MIPI display central controller; The PWM wave modulation circuit includes a first resistor, a second resistor, and a switch tube. The first end of the first resistor is used to connect to the pulse width modulation voltage terminal in series. The second end of the first resistor is connected to the control terminal of the switch tube. The first end of the switch tube is respectively connected to the first end of the second resistor and the series voltage terminal of the MIPI display central controller. The second end of the second resistor is connected to the liquid crystal display analog voltage terminal of the MIPI display central controller. The second end of the switch tube is grounded. A high and low voltage output circuit is used to output high voltage or low voltage according to the type of display screen, including a power supply chip, a third resistor, a high voltage output circuit, a low voltage output circuit and a feedback circuit. The first end of the third resistor is used to connect to the PWM analog voltage end, the second end of the third resistor is connected to the enable end of the power supply chip, the switching output end of the power supply chip is respectively connected to the input end of the high voltage output circuit and the low voltage output circuit, the output end of the high voltage output circuit is connected to the high voltage end of the MIPI display central controller, and the output end of the low voltage output circuit is connected to the low voltage end of the MIPI display central controller. The feedback circuit includes an eighth resistor and a ninth resistor. The first end of the eighth resistor is respectively connected to the switching output end of the power supply chip and the liquid crystal display analog voltage end of the MIPI display central controller, the second end of the eighth resistor is respectively connected to the feedback end of the power supply chip and the first end of the ninth resistor, and the second end of the ninth resistor is grounded.

2. The screen voltage adaptation circuit according to claim 1, characterized in that: The low-voltage output circuit includes a first switching diode, a first capacitor, a fourth resistor and a fifth resistor. The control end of the first switching diode is connected to the switching output end of the power supply chip, the upper half of the first capacitor is connected to the positive end of the first switching diode and the first end of the fourth resistor, the lower half of the first capacitor is connected to the negative end of the first switching diode, the lower half of the first capacitor is also grounded, the second end of the fourth resistor is connected to the first end of the fifth resistor, the first end of the fifth resistor is connected to the low-voltage end of the MIPI display central controller, and the second end of the fifth resistor is grounded.

3. The screen voltage adaptation circuit according to claim 2, characterized in that: The low-voltage output circuit also includes a second capacitor and a Zener diode. The upper half of the second capacitor is respectively connected to the second end of the fourth resistor and the positive end of the Zener diode, and the lower half of the second capacitor is respectively connected to the negative end of the Zener diode and the second end of the fifth resistor.

4. The screen voltage adaptation circuit according to claim 1, characterized in that: The high-voltage output circuit includes a second switching diode, a third capacitor, a sixth resistor and a seventh resistor. The switching output end of the power supply chip is respectively connected to the control end of the second switching diode, the positive end of the second switching diode and the first end of the eighth resistor, the negative end of the second switching diode is respectively connected to the upper half end of the third capacitor and the first end of the sixth resistor, the lower half end of the third capacitor is grounded, the second end of the sixth resistor is connected to the first end of the seventh resistor, the first end of the seventh resistor is also connected to the high-voltage end of the MIPI display central controller, and the second end of the seventh resistor is grounded.

5. The screen voltage adaptation circuit according to claim 4, characterized in that: The high and low voltage output circuit further includes a universal diode, a positive end of the universal diode is connected to the output end of the power chip, and a negative end of the universal diode is connected to the positive end of the second switch diode.

6. The screen voltage adaptation circuit according to claim 1, characterized in that: The feedback circuit also includes a tenth resistor and a fourth capacitor, the first end of the tenth resistor is connected to the first end of the eighth resistor, the second end of the tenth resistor is respectively connected to the upper half of the fourth capacitor and the liquid crystal display analog voltage end of the MIPI display central controller, and the lower half of the fourth capacitor is grounded.

7. The screen voltage adaptation circuit according to claim 1, characterized in that: The high and low voltage output circuit further includes an eleventh resistor, a first end of the eleventh resistor is connected to the second end of the third resistor, and a second end of the eleventh resistor is grounded.

8. The screen voltage adaptation circuit according to claim 1, characterized in that: The PWM wave modulation circuit further includes a twelfth resistor, a first end of the twelfth resistor is connected to the first end of the second resistor, and a second end of the twelfth resistor is connected to the series voltage end of the MIPI display central controller.

9. The screen voltage adaptation circuit according to claim 8, characterized in that: The PWM wave modulation circuit further includes a fifth capacitor, an upper end of the fifth capacitor is connected to the second end of the twelfth resistor, and a lower end of the fifth capacitor is grounded.

10. A vehicle-mounted central control screen, characterized in that: It comprises a display screen and the screen voltage adaptation circuit according to any one of claims 1 to 9, wherein the display screen is electrically connected to the power supply end of the screen voltage adaptation circuit.

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