TWM457201U - Multi-stage type LCD backlight power control module - Google Patents

Description

Multi-step LCD backlight power control module

The present invention relates to a backlight power control module, in particular to a multi-step LCD backlight power control module that optimizes the brightness display adjustment of the LCD panel by a multi-step control design of the LED backlight.

The current LED light module is commonly used in various illumination sources of the display panel, including as a rear projection type and side projection type light source, etc., for providing a backlight source for panel display, and the conventional LED backlight control composition is as shown in FIG. The utility model comprises a DC/DC converter 91, a processor or a microcontroller 92 (CPU or Micro-Controller Unit) and an LED lamp module 94. When the DC input is input, the DC/DC converter is used. The boosting circuit of 91 is generated as an LED backlight, and the LED backlight is controlled by the processor or the microcontroller 92 as an LED backlight constant current source 93 for driving the LED light module 94 to illuminate and adjust the brightness. .

The conventional LED backlight control structure can achieve the purpose of driving the LED lamp module 94 to illuminate and adjust the brightness. However, there is still a defect. For example, the conventional LED backlight control structure cannot make a linear change with low brightness. Control and weak brightness adjustment, when the display screen panel used enters the weak brightness adjustment section, it may show LED flickering phenomenon or cause the LED to be unable to display the closed state, causing use trouble, in other words, the conventional LED backlight control composition The adjustment section can only adjust the brightness between the full brightness (100%) and the partial dark (15%) of the LED, but cannot reach the full section between the full brightness of the LED (100%) and the full darkness of the LED (1%). Brightness adjustment is not ideal.

The above-mentioned conventional LED backlight control structure is mainly designed according to the requirements of commercial or household use, and obviously cannot meet the requirements of the normal operation of the external environmental system under the weak light source or the low-brightness panel light source in the industrial control field, for example, Military display systems, night search, in-vehicle infotainment (IVI) and even taxis, darkrooms, etc. Use the computer panel (Panel PC). Of course, if you want to solve this problem, you can add an analog-to-digital conversion (ADC) circuit and an analog linear circuit, but this will increase the hardware backlight design too much. Linear circuits and complex control have led to the increase in the cost of hardware devices and the need to increase the size of the Panel PC system. It is impossible to achieve such special application conditions that the Panel PC needs to meet the limitations of space equipment and strive to be thin and light, and also improve it. The need for breakthrough.

Therefore, how to improve the conventional LED backlight control constitutes the lack of its design, and actively increase the system hardware and machine equipment operation convenience, and has the optimization function of continuous display adjustment in the application, which should be an important solution for the industry to solve and overcome. direction.

Therefore, the creator of this case has developed a solution based on the fact that the LED backlight control constitutes its shortcomings in use and its design is not ideal. It hopes to develop a more usable use. Multi-step LCD backlight power control module with convenience and continuity adjustment, and easy to manufacture and economical, to serve the public and promote the development of this industry. Produced.

The purpose of this creation is to provide a multi-step LCD backlight power control module, which can be installed between the Panel PC and the LCD backlight module input device of the front panel of the LCD panel, and has the flexibility to select and improve the industrial control application field. In the past, the side-lit LED backlight could not follow the brightness of different parts of the screen for linear change and quickly and continuously adjust the lack of luminosity, and the non-linear discontinuous display and the adjustable brightness reduction for display can be achieved under the dimming luminosity display. Further, it has the convenience of use and adjustability.

A further object of the present invention is to provide a multi-step LCD backlight power control module, which can perform backlight brightness adjustment with the simplest and most effective structure, and has the characteristics of being light and thin, simple operation and flexible application. Industrial control applications are simpler and more efficient in combining the development and application of various LCD Panel display series products, and thus actively achieve the economic benefits and usefulness of LED backlight modules to save design costs.

Another object of the present invention is to provide a multi-step LCD backlight power control module, which can provide stable output operation of the system by using a power control firmware, so that it can be flexibly designed into multi-level input and I/O according to actual application requirements. Output backlight brightness control, can avoid adding more lines and complex Miscellaneous control loops, which can significantly reduce hardware design and component usage, while reducing the burden of future circuit failures and maintenance costs.

The technical means used in the present invention to achieve the above object includes a circuit connection: a DC/DC converter, which is a boost circuit of a DC input to generate a first-order LED backlight constant current. a second-order LED backlight constant current source; a control component that controls the modulation frequency of the second-order LED backlight constant current source; a multiplexer switch to switch the first-order LED backlight constant current source to The second-order LED backlight is fixed to a current source to generate panel brightness control; an LED light module is connected to the multiplexer switch.

The technical means of the creation further includes a circuit connection: a DC/DC converter, which is a booster circuit for a DC input to generate a first-order LED backlight constant current source; a step LED backlight constant current source; a third-order LED backlight constant current source; a control component that controls the modulation frequency of the second-order LED backlight constant current source or the modulation frequency of the third-order LED backlight constant current source a multiplexer switch to switch the first-order LED backlight constant current source to the second-order LED backlight constant current source or the third-order LED backlight constant current source to generate panel brightness control; an LED light module Connect the multiplexer switch.

In order to give your reviewers a better understanding and understanding of the technical features of the creation and the efficacies achieved, please refer to the preferred embodiment diagram and the detailed description to illustrate the following:

10‧‧‧Control Module

11‧‧‧DC/DC Converter

12‧‧‧Controls

13‧‧‧Second-order LED backlight constant current source

14‧‧‧ Third-order LED backlight constant current source

15‧‧‧Multiplexer switch

16‧‧‧LED light module

17‧‧‧Constant power flow generation circuit

18‧‧‧LED backlight power circuit

21‧‧‧Detected backlight power flow signal

22‧‧‧Multiple operation of the control unit to control the command of the third-order LED backlight constant current source

Fig. 1 is a schematic diagram showing the structure of a conventional LED backlight control.

Figure 2 is an exploded view of the backlight module of the present invention.

Figure 3 is a schematic diagram of an implementation circuit of the present invention.

Referring to FIG. 2, the multi-step LCD backlight power control module of the present invention includes a control module 10, which further includes a DC/DC converter 11 (DC/DC Converter) having a circuit connection. Control element 12, second-order LED backlight constant current source 13, third-order LED backlight constant current source 14, multiplexer switch 15 (Multiplexer) and LED lamp module 16; the DC/DC converter 11 is used as direct current Inputting the boosting circuit to generate a first-order LED backlight constant current source, that is, the DC/DC converter 11 is used to generate and illuminate the LED lamp mode The group 16 has a constant current source for controlling the brightness of the backlight power source (ie, the first-order LED backlight constant current source), and is used as the first-stage LED backlight constant power flow control. In other words, the LED backlight is controlled by the control unit 12 as one. The first-order LED backlight constant current source is used to drive the LED light module 16 (ie, the LED backlight of the LCD Panel) to illuminate. The control unit 12 is a processor (CPU) and a firmware or a microcontroller (Micro-Controller Unit, MCU for short). The second-order brightness control system is designed by the control module 10. The control member 12 controls the modulation frequency of the second-order LED backlight constant current source 13, and switches the supplied current source to the second-order LED backlight constant current source 13 by controlling the multiplexer switch 15 (Multiplexer). To produce panel brightness control.

The third-order brightness control system designed by the control module 10 controls the third-order LED backlight constant current source 14 by the control unit 12, that is, the control unit 12 performs the multiplexed modulation to correct the driving frequency downward. And simultaneously calculate the parameters, as a change of the control panel display brightness and darkness of the duty cycle (Duty Cycle) proportional adjustment, while multiplex switching to achieve lower brightness of the third-order LED backlight constant current source 14, and finally more The tool switch 15 sends out the LED light module 16 (ie, the LED backlight of the LCD Panel) to illuminate. In this way, optimal control and improved conventional techniques can be used to achieve discontinuous display after low-tuning in low-brightness LED backlight applications or to control the lack of lower LED backlight brightness.

Based on the foregoing composition design, the multi-level control mode of the multi-step LCD backlight power control module of the present creation is as follows:

First-order brightness control: a constant current source (ie, a first-order LED backlight constant current source) is controlled by a hardware DC/DC converter 11 (the first-order LED backlight constant current source), and the constant current source provides the LED lamp module 16 The brightness and brightness control of its LED light source, this first-order brightness control is generally suitable for general brightness control environment.

Second-order brightness control: The control element 12 controls the modulation frequency of the second-order LED backlight constant current source 13 to drive the DC/DC converter 11 to generate panel brightness control. In other words, the multiplexed modulation of the control member 12 downwardly corrects the driving frequency, that is, by multiplexing: (1) when the control member 12 detects that the brightness of the first-order LED backlight constant current source is close to its stable display The lower limit (2) controls the multiplexer switch 15 (Multiplexer) to switch the supplied current source to the second-order LED backlight constant current source 13, which adjusts the current frequency downward to make it more general In a slightly darker environment, the panel brightness remains stable.

Third-order brightness control: The control element 12 controls the modulation frequency of the third-order LED backlight constant current source 14 to drive the third-order LED backlight constant current source 14 to generate panel brightness control. The control member 12 for controlling the third-order LED backlight constant current source 14 and the second-order LED backlight constant current source 13 is the same control member 12; the multiplex adjustment of the control member 12 is downwardly corrected. Driving frequency, performing multiplex operation (1) when the control member 12 detects that the brightness of the second-order LED backlight constant current source 13 is close to the lower limit of its stable display; continued (2) controlling the multiplexer switch 15. Switching the supplied current source to the third-order LED backlight constant current source 14, which adjusts the current frequency downward so that the panel brightness can be stabilized in the darkest environment, so that the brightness can be continuously displayed and avoided. A blinking phenomenon occurs or the brightness is not displayed.

Please refer to Figure 3 for a schematic diagram of a circuit for implementing a multi-step LCD backlight power control module, but not limited to the circuit diagram. As shown in the figure, it includes a certain power flow generation circuit. 17 and LED backlight power supply circuit 18, when the detected backlight power flow signal 21 will be judged by the control member 12 for generating the multi-level brightness control mode operation, for example, the second-order LED backlight constant current source 13 Controlling, by the control component 12, a command transmitted from a modulation frequency of the second-order LED backlight power supply flow, and switching the current source to the second-order LED backlight constant current source 13 through the multiplexer switch 15 (Multiplexer), For the automatic operation of the second-order brightness control; and the multiplex operation of the control member controls the command 22 transmitted from the modulation frequency of the third-order LED backlight constant current source, through the multiplexer switch 15 (Multiplexer) The current source switches to the third-order brightness control mode.

The reason is that the multi-step LCD backlight power control module of the present invention can be used between the Panel PC and the LCD backlight module input device of the LCD liquid crystal panel by the above-mentioned composition, and has the flexibility to select and use in the industrial control application field. It can achieve the positive effect of non-linear discontinuous display and adjustable brightness reduction for display under the dim luminosity display. It has the convenience and adjustability of use; and this creation can perform backlight brightness with the simplest and most effective structure. The adjustment and use of the characteristics of light and thin, simple operation and flexible application make the industrial control application more simple and efficient in the development and application of various LCD Panel display series products, and actively achieve the economic benefits of saving the design cost of the LED backlight module and The utility model can also provide the stable output of the system output by using the power control firmware, so that the multi-step input and the I/O output backlight brightness control can be flexibly designed according to the actual application requirements, thereby avoiding the addition of many lines and complicated control loops. ,and then It can greatly reduce the hardware design and component usage, and at the same time reduce the burden of circuit failure and maintenance costs in the future.

In summary, this creation has indeed met the requirements of the new patent, and filed a patent application in accordance with the law. However, the above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, the shape, structure, characteristics and spirit described in the scope of the patent application are equally changed and modified. , should be included in the scope of the patent application of this creation.

10‧‧‧Control Module

11‧‧‧DC/DC Converter

12‧‧‧Controls

13‧‧‧Second-order LED backlight constant current source

14‧‧‧ Third-order LED backlight constant current source

15‧‧‧Multiplexer switch

16‧‧‧LED light module

Claims (13)

A multi-step LCD backlight power control module includes a circuit connection: a DC/DC converter, which is a boost circuit of a DC input to generate a first-order LED backlight constant current source a second-order LED backlight constant current source; a control component that controls a modulation frequency of the second-order LED backlight constant current source; and a multiplexer switch to switch the LED backlight current source to the second-order LED The backlight is fixed to the current source to generate panel brightness control; an LED light module is connected to the multiplexer switch. The multi-step LCD backlight power control module of claim 1, wherein the control component is a processor and a firmware or a microcontroller. The multi-level LCD backlight power supply control module of claim 1, further comprising a third-order LED backlight constant current source, and the control element controls the third-order LED backlight constant current source The frequency is modulated, and the second-stage LED backlight constant current source is switched to the third-order LED backlight constant current source by the multiplexer switch to generate panel brightness control. The multi-step LCD backlight power supply control module of claim 3, wherein the control component performs a multiplexed modulation to correct the driving frequency downward, and simultaneously calculates a parameter as a change of the display panel to display the brightness and brightness. Control cycle proportional adjustment. The multi-level LCD backlight power supply control module of claim 1, wherein the control component is controlled after detecting that the brightness of the first-order LED backlight constant current source is close to a lower limit of its stable display. The multiplexer switch switches the supplied current source to the second order LED backlight constant current source. The multi-step LCD backlight power supply control module of claim 4, wherein the control component is continuously controlled when the brightness of the second-order LED backlight constant current source is detected to be close to a lower limit of the stable display thereof. The multiplexer switch switches the supplied current source to a third-order LED backlight constant current source. A multi-step LCD backlight power control module includes a circuit connection: A DC/DC converter, which is a booster circuit for DC input to generate a first-order LED backlight constant current source; a second-order LED backlight constant current source; and a third-order LED backlight a constant current source; a control component for controlling a modulation frequency of the second-order LED backlight constant current source or a modulation frequency of the third-order LED backlight constant current source; a multiplexer switch to enable the LED backlight current source Switching to the second-order LED backlight constant current source or the third-order LED backlight constant current source to generate panel brightness control; an LED light module is connected to the multiplexer switch. The multi-step LCD backlight power control module of claim 7, wherein the control component is a processor and a firmware or a microcontroller. The multi-step LCD backlight power control module of claim 7, wherein the control device controls the multiplexer switch to switch the first-order LED backlight constant current source to the second-order LED backlight Current source to produce panel brightness control. The multi-level LCD backlight power supply control module of claim 7, wherein the control device controls the multiplexer switch to switch the second-order LED backlight constant current source to the third-order LED backlight constant current. Source to produce panel brightness control. The multi-step LCD backlight power supply control module of claim 7, wherein the control component performs a multiplexed modulation to correct the driving frequency downward, and simultaneously calculates a parameter as a change of the brightness and brightness of the control panel. Control cycle proportional adjustment. The multi-step LCD backlight power control module according to claim 9, wherein the control component is controlled after detecting that the brightness of the first-order LED backlight constant current source is close to a lower limit of the stable display thereof. The multiplexer switch switches the supplied current source to the second order LED backlight constant current source. The multi-step LCD backlight power supply control module of claim 10, wherein the control component is continuously controlled when the brightness of the second-order LED backlight constant current source is detected to be close to a lower limit of the stable display thereof. The multiplexer switch switches the supplied current source to the third-order LED backlight Stream source.