Display screen backlight power-on regulation and control circuit

Abstract

The utility model discloses a display screen backlight power-on regulation and control circuit, a display SOC is built in a display screen, and the display screen backlight power-on regulation and control circuit comprises a power supply module, a voltage regulation module and a brightness regulation and control module. The power supply module is connected with an external power supply end; and the power supply module is also respectively connected with the power supply input end of the display SOC and the backlight control end of the display screen. The brightness regulation and control module is respectively connected with the power supply module and the voltage regulation module, and the brightness regulation and control module is used for controlling the power supply of the power supply module to the rear end of the circuit after controlling the backlight of the display screen to be turned on at the lowest brightness; according to the utility model, the phenomena of short-time blurred screen and splash screen which can not be avoided at the moment when the display screen is started and powered on are reduced to the minimum, and bad visual stimulation of a user is effectively avoided, so that the impression experience is effectively improved. Moreover, when the display screen device is in a standby state, the standby state is maintained based on the single-chip microcomputer chip with small power, so that the standby power consumption of the display screen is obviously reduced.

Description

Technical Field

[0001] The utility model relates to a display screen backlight technology, in particular to a display screen backlight power-on control circuit. Background Art

[0002] The backlight control of existing display screens when turned on is generally to use the SOC chip to automatically adjust PWM and brightness after the backlight is turned on. However, it is found that when the display screen device is powered on, the backlight of the display screen is instantly subjected to a short electrical pulse when powered on, and there is a buffer time before the SOC chip stabilizes the control. The control of the SOC chip and the hardware circuit will not work when the display screen is just powered on, and the display screen will inevitably have short-term screen noise and screen flashing, causing users to have bad visual stimulation and viewing experience.

[0003] Furthermore, most existing SOC embedded systems run the Linux operating system, so it is very difficult to make such a large system low-power in standby mode, resulting in unnecessary energy waste during standby mode. Utility Model Content

[0004] The purpose of the utility model is to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a display screen backlight power-on control circuit. The technical solution provided by the utility model is: to provide a display screen backlight power-on control circuit, a display screen backlight power-on control circuit, a display screen backlight power-on control circuit, a display screen built-in display SOC, including: a power module, a voltage regulation module, a brightness control module;

[0005] Preferably, the power module is connected to an external power supply terminal;

[0006] Preferably, the power module is also connected to the power supply input terminal of the display SOC and the control terminal of the backlight of the display screen respectively.

[0007] Preferably, the brightness control module is connected to the power module and the voltage regulation module respectively, and the brightness control module is used to control the backlight of the display screen to turn on at the lowest brightness and then control the power module to supply power to the back end of the circuit;

[0008] Preferably, the brightness control module includes: a single chip microcomputer chip, a third transistor;

[0009] Preferably, the power input terminal of the single-chip microcomputer chip is connected to the output terminal of the power module; the IO terminal of the single-chip microcomputer chip is respectively connected to the power module and the third transistor; and the third transistor is connected to the backlight control terminal of the display screen.

[0010] Preferably, the power supply module includes: a first transistor and a second transistor; the first connection end of the first transistor is connected to the external power supply end, and the voltage of the external power supply end is 24V; the second connection end of the first transistor is connected to the third connection end of the second transistor; the third connection end of the first transistor is connected to the power supply input end of the SOC main control chip; the first connection end of the second transistor is connected to the brightness control module; the second connection end of the second transistor is grounded.

[0011] Preferably, the power supply module also includes: a first capacitor, a second capacitor, a third capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor; the external power supply end is grounded via the first capacitor; the second capacitor and the first resistor are both connected to the first connection end and the second connection end of the first transistor; the third connection end of the first transistor is grounded via the third capacitor; the second resistor is respectively connected to the second connection end of the first transistor and the third connection end of the second transistor; the third resistor is respectively connected to the first connection end of the second transistor and the brightness control module; the first connection end of the second transistor is grounded via the fourth resistor.

[0012] Preferably, the voltage regulation module includes: a power converter chip, a first diode; the input end of the power converter chip is connected to the external power supply end; the output end of the power converter chip is connected to the brightness control module; the output voltage of the output end of the power converter chip is 3V.

[0013] Preferably, the voltage regulation module also includes: a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor and a first inductor; the external power supply end is grounded via the fourth capacitor and the fifth capacitor; the first inductor is respectively connected to the output end of the power converter chip and the brightness control module; the output end of the power converter chip is grounded via the sixth capacitor and the seventh capacitor.

[0014] Preferably, the IO terminal of the single-chip microcomputer chip includes: a first IO terminal and a second IO terminal; the power input terminal of the single-chip microcomputer chip is connected to the output terminal of the power converter chip; the first IO terminal of the single-chip microcomputer chip is connected to the first connection terminal of the second transistor; the second IO terminal of the single-chip microcomputer chip is connected to the first connection terminal of the third transistor; the second connection terminal of the third transistor is grounded; and the third connection terminal of the third transistor is connected to the backlight control terminal of the display screen.

[0015] Preferably, the brightness control module also includes: a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor; the fifth resistor is respectively connected to the second IO terminal of the single-chip chip and the first connection terminal of the third transistor; the sixth resistor is respectively connected to the backlight control terminal of the display screen and the first connection terminal of the third transistor; the first connection terminal of the third transistor is connected to the third connection terminal of the third transistor via the seventh resistor and the eighth resistor.

[0016] The beneficial effect of the utility model is: by setting up a display screen backlight power-on control circuit, the backlight brightness is controlled by the brightness control module timing before the display screen backlight is subjected to a short-term electrical pulse and the SOC main control chip is stabilized and buffered, so that the short-term screen noise and screen flickering that inevitably occur when the display screen is powered on are reduced to a minimum, so that the human eye senses can be ignored, effectively avoiding the user's adverse visual stimulation, thereby effectively improving the viewing experience. Furthermore, when the display screen device is in standby mode, compared with an embedded system based on an SOC main control chip, the utility model maintains standby mode based on a low-power single-chip microcomputer chip, thereby significantly reducing the standby power consumption of the display screen and achieving the effect of energy saving and consumption reduction. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a structural schematic diagram of a display screen backlight power-on control circuit of a preferred embodiment of the utility model;

[0019] Figure 2 This is a schematic diagram of the structure of a power module of a display backlight power-on control circuit in a preferred embodiment of the utility model;

[0020] Figure 3 This is a schematic diagram of the structure of a voltage regulating module of a display backlight power-on regulating circuit in a preferred embodiment of the utility model;

[0021] Figure 4 This is a schematic diagram of the structure of a brightness control module of a display backlight power-on control circuit in a preferred embodiment of the utility model;

[0022] In the figure:

[0023] Q1 - first transistor, Q2 - second transistor, Q3 - third transistor, U1 - power converter chip, U2 - single chip microcomputer chip;

[0024] 24V_control - external power supply end, VIN - input end of power converter chip, OUTPUT - output end of power converter chip, VCC - VCC network, 3V3_VOUT - 3V output voltage, 24V_PWR - SOC - main control chip, BL_PWM - positive backlight control end of display screen, BACKL_PWM - negative backlight control end of display screen, IO 1 - first IO end, IO2 - second IO end, VIN2 - input end of microcontroller chip, GND - ground end. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the utility model clearer, the following will refer to the drawings in the embodiments of the utility model to clearly and completely describe the technical solution of the utility model through the implementation method. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0026] Reference Figures 1 to 4 , the preferred embodiment of the utility model provides a display screen backlight power-on control circuit, a display screen backlight power-on control circuit, the display screen has a built-in display SOC, including: a power supply module, a voltage regulation module, and a brightness control module;

[0027] In a preferred embodiment, the power module is connected to an external power supply terminal;

[0028] In a preferred embodiment, the power module is also connected to the power supply input terminal of the display SOC and the control terminal of the backlight of the display screen respectively.

[0029] In a preferred embodiment, the brightness control module is connected to the power module and the voltage regulation module respectively, and the brightness control module is used to control the backlight of the display screen to turn on at the lowest brightness and then control the power module to supply power to the back end of the circuit;

[0030] In a preferred embodiment, the brightness control module includes: a single chip microcomputer chip U2, a third transistor Q3;

[0031] In a preferred embodiment, the power input terminal of the single-chip microcomputer chip U2 is connected to the output terminal of the power module; the IO terminal of the single-chip microcomputer chip U2 is respectively connected to the power module and the third transistor Q3; the third transistor Q3 is connected to the backlight control terminal of the display screen.

[0032] In a preferred embodiment, the power supply module includes: a first transistor Q1 and a second transistor Q2; the first connection end of the first transistor Q1 is connected to the external power supply end, and the voltage of the external power supply end is 24V; the second connection end of the first transistor Q1 is connected to the third connection end of the second transistor Q2; the third connection end of the first transistor Q1 is connected to the power supply input end of the SOC main control chip; the first connection end of the second transistor Q2 is connected to the brightness control module; the second connection end of the second transistor Q2 is grounded.

[0033] In a preferred embodiment, the power supply module also includes: a first capacitor, a second capacitor, a third capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor; the external power supply end is grounded via the first capacitor; the second capacitor and the first resistor are both connected to the first connection end and the second connection end of the first transistor Q1; the third connection end of the first transistor Q1 is grounded via the third capacitor; the second resistor is respectively connected to the second connection end of the first transistor Q1 and the third connection end of the second transistor Q2; the third resistor is respectively connected to the first connection end of the second transistor Q2 and the brightness control module; the first connection end of the second transistor Q2 is grounded via the fourth resistor.

[0034] In a preferred embodiment, the voltage regulation module includes: a power converter chip U1 and a first diode; the input end of the power converter chip U1 is connected to the external power supply end; the output end of the power converter chip U1 is connected to the brightness control module; the output voltage of the output end of the power converter chip U1 is 3V.

[0035] In a preferred embodiment, the voltage regulation module also includes: a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor and a first inductor; the external power supply end is grounded via the fourth capacitor and the fifth capacitor; the first inductor is respectively connected to the output end of the power converter chip U1 and the brightness control module; the output end of the power converter chip U1 is grounded via the sixth capacitor and the seventh capacitor.

[0036] In a preferred embodiment, the IO end of the single-chip microcomputer chip U2 includes: a first IO end and a second IO end; the power input end of the single-chip microcomputer chip U2 is connected to the output end of the power converter chip U1; the first IO end of the single-chip microcomputer chip U2 is connected to the first connection end of the second transistor Q2; the second IO end of the single-chip microcomputer chip U2 is connected to the first connection end of the third transistor Q3; the second connection end of the third transistor Q3 is grounded; the third connection end of the third transistor Q3 is connected to the backlight control end of the display screen.

[0037] In a preferred embodiment, the brightness control module also includes: a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor; the fifth resistor is respectively connected to the second IO terminal of the single-chip chip U2 and the first connection terminal of the third transistor Q3; the sixth resistor is respectively connected to the backlight control terminal of the display screen and the first connection terminal of the third transistor Q3; the first connection terminal of the third transistor Q3 is connected to the third connection terminal of the third transistor Q3 via the seventh resistor and the eighth resistor.

[0038] In a preferred embodiment, the second transistor Q2 adopts a P-channel enhancement type field effect transistor, the power converter chip U1 adopts a BUCK DC-DC converter, the microcontroller chip U2 adopts a 51 microcontroller, the first transistor Q1 adopts an N-channel enhancement type field effect transistor, and the third transistor Q3 adopts an NPN transistor.

[0039] The device with a display screen is powered by a 24V external power supply. When the adapter is plugged in, the 24V is stepped down to 3V by the power converter chip U1 to power the microcontroller chip U2, so that the microcontroller chip U2 works normally. The gate G of the second diode Q2 remains at a low level. At this time, the second diode Q2 works in the cut-off state and does not conduct. The gate G of the first transistor Q1 is pulled up to 24V to output a high level, so the first transistor Q1 works in the cut-off state and does not conduct. That is, since the second transistor Q2 is cut off, the first transistor Q1 is also cut off, and the 24V coming in from the external power supply will not power the subsequent circuits, so that the microcontroller chip U1 is the first to work.

[0040] When the power button is pressed, the microcontroller chip U2 receives a low-level 0V signal, controls the first IO terminal of the microcontroller chip U2 to output a high-level 3V, and the gate G of the second transistor Q2 outputs a high level. At this time, the second transistor Q2 is turned on, and the gate G of the first transistor Q1 is pulled down to a low level of 0V. At this time, the source S voltage of the first transistor Q1 is greater than the gate G voltage of the first transistor Q1, and the first transistor Q1 is turned on. The 24V voltage can be conducted from the source S to the drain D, that is, the first transistor Q1 and the second transistor Q2 are turned on, so that 24V is supplied to the subsequent circuits, and the SOC main control chip at the back end starts working.

[0041] Since it takes a certain amount of time for the main control system to run and output stably, the control of the SOC chip and the hardware circuit will not work when the display screen is just powered on, and the display screen will inevitably have short-term screen noise and flashing. Now, the second IO terminal of the single-chip microcomputer chip U2 is used to control the backlight brightness a few seconds before powering on. That is, after the single-chip microcomputer chip U2 detects that the key is pressed, it controls the first IO terminal to output a high level to power the display screen, and controls the second IO terminal to output a high level of 3V to control the third transistor Q3 to turn on. After the third transistor Q3 is turned on, the driving voltage of the display screen backlight is pulled down to close to 0V, so that the backlight brightness is 0. After the first delay time of 2s, the system has been running, and the differential signal and the system are also stable. At this time, the second IO terminal of the single-chip microcomputer chip U2 is controlled to be in a high-impedance state, and the SOC main control chip outputs a PWM signal to control the switch of the third transistor Q3, so as to adjust the backlight brightness normally. The display device is maintained by a 3V single-chip microcomputer chip when in standby mode. Its power consumption is significantly lower than that of a 24V SOC main control chip, greatly reducing energy waste.

[0042] The beneficial effect of the utility model is: by setting up a display screen backlight power-on control circuit, the backlight brightness is controlled by the brightness control module timing before the display screen backlight is subjected to a short-term electrical pulse and the SOC main control chip is stabilized and buffered, so that the short-term screen noise and screen flickering that inevitably occur when the display screen is powered on are reduced to a minimum, so that the human eye senses can be ignored, effectively avoiding the user's adverse visual stimulation, thereby effectively improving the viewing experience. Furthermore, when the display screen device is in standby mode, compared with an embedded system based on an SOC main control chip, the utility model maintains standby mode based on a low-power single-chip microcomputer chip, thereby significantly reducing the standby power consumption of the display screen and achieving the effect of energy saving and consumption reduction.

[0043] In the description of the present utility model, "several" means more than one, "many" means more than two, "greater than", "less than", "exceed" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself. If there is a description of "first" or "second", it is only used to distinguish the technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0044] In the description of the present utility model, unless otherwise clearly defined, words such as "setting" should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meaning of the above words in the present utility model in combination with the specific content of the technical solution.

[0045] In the description of the utility model, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0046] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention is described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A display screen backlight power-on control circuit, wherein the display screen has a built-in display SOC, characterized in that: include: Power module, voltage regulation module, brightness control module; The power module is connected to an external power supply terminal; The power supply module is also connected to the power supply input terminal of the display SOC and the control terminal of the backlight of the display screen respectively; The brightness control module is connected to the power module and the voltage regulating module respectively, and the brightness control module is used to control the backlight of the display screen to turn on at the lowest brightness and then control the power module to supply power to the back end of the circuit; The brightness control module includes: a single chip microcomputer chip and a third transistor; The power input terminal of the single-chip microcomputer chip is connected to the output terminal of the power module; The IO terminals of the single-chip microcomputer chip are respectively connected to the power module and the third transistor; The third transistor is connected to the backlight control terminal of the display screen.

2. A display backlight power-on control circuit according to claim 1, characterized in that: The power module comprises: a first triode and a second triode; The first connection end of the first transistor is connected to the external power supply end, and the voltage of the external power supply end is 24V; The second connection end of the first transistor is connected to the third connection end of the second transistor; The third connection end of the first transistor is connected to the power supply input end of the SOC main control chip; The first connection end of the second transistor is connected to the brightness control module; The second connection end of the second transistor is grounded.

3. A display screen backlight power-on control circuit according to claim 2, characterized in that: The power module further includes: a first capacitor, a second capacitor, a third capacitor, a first resistor, a second resistor, a third resistor and a fourth resistor; The external power supply end is grounded via the first capacitor; The second capacitor and the first resistor are both connected to the first connection end and the second connection end of the first transistor; The third connection end of the first transistor is grounded via the third capacitor; The second resistor is connected to the second connection terminal of the first transistor and the third connection terminal of the second transistor respectively; The third resistor is connected to the first connection end of the second transistor and the brightness control module respectively; The first connection end of the second transistor is grounded via the fourth resistor.

4. A display screen backlight power-on control circuit according to claim 3, characterized in that: The voltage regulation module includes: a power converter chip and a first diode; The input end of the power converter chip is connected to the external power supply end; The output end of the power converter chip is connected to the brightness control module; The output voltage of the output end of the power converter chip is 3V.

5. A display screen backlight power-on control circuit according to claim 4, characterized in that: The voltage regulating module further includes: a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor and a first inductor; The external power supply end is grounded via the fourth capacitor and the fifth capacitor; The first inductor is connected to the output end of the power converter chip and the brightness control module respectively; The output end of the power converter chip is grounded via the sixth capacitor and the seventh capacitor.

6. A display screen backlight power-on control circuit according to claim 5, characterized in that: The IO terminals of the single-chip microcomputer chip include: a first IO terminal and a second IO terminal; The power input terminal of the single-chip microcomputer chip is connected to the output terminal of the power converter chip; The first IO terminal of the single-chip microcomputer chip is connected to the first connection terminal of the second transistor; The second IO terminal of the single-chip microcomputer chip is connected to the first connection terminal of the third transistor; The second connection end of the third transistor is grounded; The third connection end of the third transistor is connected to the backlight control end of the display screen.

7. A display screen backlight power-on control circuit according to claim 6, characterized in that: The brightness control module further includes: a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor; The fifth resistor is connected to the second IO terminal of the single-chip chip and the first connection terminal of the third transistor respectively; The sixth resistor is connected to the backlight control terminal of the display screen and the first connection terminal of the third transistor respectively; The first connection end of the third transistor is connected to the third connection end of the third transistor via the seventh resistor and the eighth resistor.

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